When the target of the compiler is ES2015 or newer then we should
be generating `let` and `const` variable declarations rather than `var`.
PR Close#38775
The cast to `ts.Identifier` was a hack that "just happened to work".
The new approach is more robust and doesn't have to undermine
the type checker.
PR Close#38775
This commit re-enables some tests that were temporarily disabled on Windows,
as they failed on native Windows CI. The Windows filesystem emulation has
been corrected in an earlier commit, such that the original failure would
now also occur during emulation on Linux CI.
PR Close#37782
In native windows, the drive letter is a capital letter, while our Windows
filesystem emulation would use lowercase drive letters. This difference may
introduce tests to behave differently in native Windows versus emulated
Windows, potentially causing unexpected CI failures on Windows CI after a PR
has been merged.
Resolves FW-2267
PR Close#37782
The logic for computing identifiers, specifically for bound attributes
can be simplified by using the value span of the binding rather than the
source span.
PR Close#38899
Common AST formats such as TS and Babel do not use a separate
node for comments, but instead attach comments to other AST nodes.
Previously this was worked around in TS by creating a `NotEmittedStatement`
AST node to attach the comment to. But Babel does not have this facility,
so it will not be a viable approach for the linker.
This commit refactors the output AST, to remove the `CommentStmt` and
`JSDocCommentStmt` nodes. Instead statements have a collection of
`leadingComments` that are rendered/attached to the final AST nodes
when being translated or printed.
PR Close#38811
This change prevents comments from a resolved node from appearing at
each location the resolved expression is used and also prevents callers
of `Scope#resolve` from accidentally modifying / adding comments to the
declaration site.
PR Close#38857
When type-checking a component, the declaring NgModule scope is used
to create a directive matcher that contains flattened directive metadata,
i.e. the metadata of a directive and its base classes. This computation
is done for all components, whereas the type-check scope is constant per
NgModule. Additionally, the flattening of metadata is constant per
directive instance so doesn't necessarily have to be recomputed for
each component.
This commit introduces a `TypeCheckScopes` class that is responsible
for flattening directives and computing the scope per NgModule. It
caches the computed results as appropriate to avoid repeated computation.
PR Close#38539
For the compilation of a component, the compiler has to prepare some
information about the directives and pipes that are used in the template.
This information includes an expression for directives/pipes, for usage
within the compilation output. For large NgModule compilation scopes
this has shown to introduce a performance hotspot, as the generation of
expressions is quite expensive. This commit reduces the performance
overhead by only generating expressions for the directives/pipes that
are actually used within the template, significantly cutting down on
the compiler's resolve phase.
PR Close#38539
Adds `TemplateTypeChecker` operation to retrieve the `Symbol` of a
`TmplAstVariable` or `TmplAstReference` in a template.
Sometimes we need to traverse an intermediate variable declaration to arrive at
the correct `ts.Symbol`. For example, loop variables are declared using an intermediate:
```
<div *ngFor="let user of users">
{{user.name}}
</div>
```
Getting the symbol of user here (from the expression) is tricky, because the TCB looks like:
```
var _t0 = ...; // type of NgForOf
var _t1: any; // context of embedded view for NgForOf structural directive
if (NgForOf.ngTemplateContextGuard(_t0, _t1)) {
// _t1 is now NgForOfContext<...>
var _t2 = _t1.$implicit; // let user = '$implicit'
_t2.name; // user.name expression
}
```
Just getting the `ts.Expression` for the `AST` node `PropRead(ImplicitReceiver, 'user')`
via the sourcemaps will yield the `_t2` expression. This function recognizes that `_t2`
is a variable declared locally in the TCB, and actually fetch the `ts.Symbol` of its initializer.
These special handlings show the versatility of the `Symbol`
interface defined in the API. With this, when we encounter a template variable,
we can provide the declaration node, as well as specific information
about the variable instance, such as the `ts.Type` and `ts.Symbol`.
PR Close#38618
Adds support to the `TemplateTypeChecker` to get a `Symbol` of an AST
expression in a component template.
Not all expressions will have `ts.Symbol`s (e.g. there is no `ts.Symbol`
associated with the expression `a + b`, but there are for both the a and b
nodes individually).
PR Close#38618
Adds support to the `TemplateTypeChecker` for retrieving a `Symbol` for
`TmplAstTemplate` and `TmplAstElement` nodes in a component template.
PR Close#38618
Specifically, this commit adds support for retrieving a `Symbol` from a
`TmplAstBoundEvent` or `TmplAstBoundAttribute`. Other template nodes
will be supported in following commits.
PR Close#38618
The statements generated in the TCB are optimized for performance and producing diagnostics.
These optimizations can result in generating a TCB that does not have all the information
needed by the `TemplateTypeChecker` for retrieving `Symbol`s. For example, as an optimization,
the TCB will not generate variable declaration statements for directives that have no
references, inputs, or outputs. However, the `TemplateTypeChecker` always needs these
statements to be present in order to provide `ts.Symbol`s and `ts.Type`s for the directives.
This commit adds logic to the TCB generation to ensure the required
information is available in a form that the `TemplateTypeChecker` can
consume. It also adds an option to the `NgCompiler` that makes this
generation configurable.
PR Close#38618
This commit defines the interfaces which outline the information the
`TemplateTypeChecker` can return when requesting a Symbol for an item in the
`TemplateAst`.
Rather than providing the `ts.Symbol`, `ts.Type`, etc.
information in several separate functions, the `TemplateTypeChecker` can
instead provide all the useful information it knows about a particular
node in the `TemplateAst` and allow the callers to determine what to do
with it.
PR Close#38618
When type-checking a component, the declaring NgModule scope is used
to create a directive matcher that contains flattened directive metadata,
i.e. the metadata of a directive and its base classes. This computation
is done for all components, whereas the type-check scope is constant per
NgModule. Additionally, the flattening of metadata is constant per
directive instance so doesn't necessarily have to be recomputed for
each component.
This commit introduces a `TypeCheckScopes` class that is responsible
for flattening directives and computing the scope per NgModule. It
caches the computed results as appropriate to avoid repeated computation.
PR Close#38539
For the compilation of a component, the compiler has to prepare some
information about the directives and pipes that are used in the template.
This information includes an expression for directives/pipes, for usage
within the compilation output. For large NgModule compilation scopes
this has shown to introduce a performance hotspot, as the generation of
expressions is quite expensive. This commit reduces the performance
overhead by only generating expressions for the directives/pipes that
are actually used within the template, significantly cutting down on
the compiler's resolve phase.
PR Close#38539
The type-to-value conversion could previously crash if a symbol was
resolved that does not have any declarations, e.g. because it's imported
from a missing module. This would typically result in a semantic
TypeScript diagnostic and halt further compilation, therefore not
reaching the type-to-value conversion logic. In Bazel however, it turns
out that Angular semantic diagnostics are requested even if there are
semantic TypeScript errors in the program, so it would then reach the
type-to-value conversation and crash.
This commit fixes the unsafe access and adds a test that ignores the
TypeScript semantic error, effectively replicating the situation as
experienced under Bazel.
Fixes#38670
PR Close#38684
Previously, localized strings had very limited or incorrect source-mapping
information available.
Now the i18n AST nodes and related output AST nodes include source-span
information about message-parts and placeholders - including closing tag
placeholders.
This information is then used when generating the final localized string
ASTs to ensure that the correct source-mapping is rendered.
See #38588 (comment)
PR Close#38645
Previously this interface was mostly stored in compiler-cli, but it
contains some properties that would be useful for compiling the
"declare component" prelink code.
This commit moves some of the interface over to the compiler
package so that it can be referenced there without creating a
circular dependency between the compiler and compiler-cli.
PR Close#38594
The `R3TargetBinder` accepts an interface for directive metadata which
declares types for `input` and `output` objects. These types convey the
mapping between the property names for an input or output and the
corresponding property name on the component class. Due to
`R3TargetBinder`'s requirements, this mapping was specified with property
names as keys and field names as values.
However, because of duck typing, this interface was accidentally satisifed
by the opposite mapping, of field names to property names, that was produced
in other parts of the compiler. This form more naturally represents the data
model for inputs.
Rather than accept the field -> property mapping and invert it, this commit
introduces a new abstraction for such mappings which is bidirectional,
eliminating the ambiguous plain object type. This mapping uses new,
unambiguous terminology ("class property name" and "binding property name")
and can be used to satisfy both the needs of the binder as well as those of
the template type-checker (field -> property).
A new test ensures that the input/output metadata produced by the compiler
during analysis is directly compatible with the binder via this unambiguous
new interface.
PR Close#38685
A recent change to `@angular/localize` brought in the `AbsoluteFsPath` type
from the `@angular/compiler-cli`. But this brought along with it a reference
to NodeJS typings - specifically the `FileSystem` interface refers to the
`Buffer` type from NodeJS.
This affects compilation of `@angular/localize` code that will be run in
the browser - for example projects that reference `loadTranslations()`.
The compilation breaks if the NodeJS typings are not included in the build.
Clearly it is not desirable to have these typings included when the project
is not targeting NodeJS.
This commit replaces references to the NodeJS `Buffer` type with `Uint8Array`,
which is available across all platforms and is actually the super-class of
`Buffer`.
Fixes#38692
PR Close#38700
Previously, the compiler was not able to display template parsing errors as
true `ts.Diagnostic`s that point inside the template. Instead, it would
throw an actual `Error`, and "crash" with a stack trace containing the
template errors.
Not only is this a poor user experience, but it causes the Language Service
to also crash as the user is editing a template (in actuality the LS has to
work around this bug).
With this commit, such parsing errors are converted to true template
diagnostics with appropriate span information to be displayed contextually
along with all other diagnostics. This majorly improves the user experience
and unblocks the Language Service from having to deal with the compiler
"crashing" to report errors.
PR Close#38576
The template type-checking engine includes utilities for creating
`ts.Diagnostic`s for component templates. Previously only the template type-
checker itself created such diagnostics. However, the template parser also
produces errors which should be represented as template diagnostics.
This commit prepares for that conversion by extracting the machinery for
producing template diagnostics into its own sub-package, so that other parts
of the compiler can depend on it without depending on the entire template
type-checker.
PR Close#38576
Previously, the `sourceSpan` and `startSourceSpan` were the same
object, which meant that you had the following situation:
```
element = <div>some content</div>
sourceSpan = <div>
startSourceSpan = <div>
endSourceSpan = </div>
```
This made `sourceSpan` redundant and meant that if you
wanted a span for the whole element including its content
and closing tag, it had to be computed.
Now `sourceSpan` is separated from `startSourceSpan`
resulting in:
```
element = <div>some content</div>
sourceSpan = <div>some content</div>
startSourceSpan = <div>
endSourceSpan = </div>
```
PR Close#38581
Previously the lexer was responsible for deciding whether an "inline"
template should also have its line-endings normalized.
Now this decision is made higher up in the call stack to allow more
flexibility in the parser/lexer.
PR Close#38581
With Typescript 4, `ts.updateIdentifier` is no longer available.
Calling `ts.updateIdentifier` used to return the same node when
`typeArguments` was `undefined` because `node.typeArguments`
was also `undefined`.
Relevant TS code:
```js
function updateIdentifier(node, typeArguments) {
return node.typeArguments !== typeArguments
? updateNode(createIdentifier(ts.idText(node), typeArguments), node)
: node;
}
```
PR Close#38076
Prior to this change, the unary + and - operators would be parsed as `x - 0`
and `0 - x` respectively. The runtime semantics of these expressions are
equivalent, however they may introduce inaccurate template type checking
errors as the literal type is lost, for example:
```ts
@Component({
template: `<button [disabled]="isAdjacent(-1)"></button>`
})
export class Example {
isAdjacent(direction: -1 | 1): boolean { return false; }
}
```
would incorrectly report a type-check error:
> error TS2345: Argument of type 'number' is not assignable to parameter
of type '-1 | 1'.
Additionally, the translated expression for the unary + operator would be
considered as arithmetic expression with an incompatible left-hand side:
> error TS2362: The left-hand side of an arithmetic operation must be of
type 'any', 'number', 'bigint' or an enum type.
To resolve this issues, the implicit transformation should be avoided.
This commit adds a new unary AST node to represent these expressions,
allowing for more accurate type-checking.
Fixes#20845Fixes#36178
PR Close#37918
We had a couple of places where we were assuming that if a particular
symbol has a value, then it will exist at runtime. This is true in most cases,
but it breaks down for `const` enums.
Fixes#38513.
PR Close#38542
This commit adds a `getTemplateOfComponent` method to the
`TemplateTypeChecker` API, which retrieves the actual nodes parsed and used
by the compiler for template type-checking. This is advantageous for the
language service, which may need to query other APIs in
`TemplateTypeChecker` that require the same nodes used to bind the template
while generating the TCB.
Fixes#38352
PR Close#38355
For a template that contains for example `<span *ngIf="first"></span>`
there's no need to render the `NgIf` guard expression, as the child
scope does not have any type-checking statements, so any narrowing
effect of the guard is not applicable.
This seems like a minor improvement, however it reduces the number of
flow-node antecedents that TypeScript needs to keep into account for
such cases, resulting in an overall reduction of type-checking time.
PR Close#38418
The template type-checker would always generate a directive declaration
even if its type was never used. For example, directives without any
input nor output bindings nor exportAs references don't need the
directive to be declared, as its type would never be used.
This commit makes the `TcbOp`s that are responsible for declaring a
directive as optional, such that they are only executed when requested
from another operation.
PR Close#38418
The template type-checker would generate a statement with a call
expression for all DOM elements in a template of the form:
```
const _t1 = document.createElement("div");
```
Profiling has shown that this is a particularly expensive call to
perform type inference on, as TypeScript needs to perform signature
selection of `Document.createElement` and resolve the exact type from
the `HTMLElementTagNameMap`. However, it can be observed that the
statement by itself does not contribute anything to the type-checking
result if `_t1` is not actually used anywhere, which is only rarely the
case---it requires that the element is referenced by its name from
somewhere else in the template. Consequently, the type-checker can skip
generating this statement altogether for most DOM elements.
The effect of this optimization is significant in several phases:
1. Less type-check code to generate
2. Less type-check code to emit and parse again
3. No expensive type inference to perform for the call expression
The effect on phase 3 is the most significant here, as type-checking is
not currently incremental in the sense that only phases 1 and 2 can
be reused from a prior compilation. The actual type-checking of all
templates in phase 3 needs to be repeated on each incremental
compilation, so any performance gains we achieve here are very
beneficial.
PR Close#38418
The compiler does not currently report errors when there's an `@Input()`
for a `private`, `protected`, or `readonly` directive/component class member.
This change adds an option to enable reporting errors when a template
attempts to bind to one of these restricted input fields.
PR Close#38249
Prior to this change, the template type checker would always use a
type-constructor to instantiate a directive. This type-constructor call
serves two purposes:
1. Infer any generic types for the directive instance from the inputs
that are passed in.
2. Type check the inputs that are passed into the directive's inputs.
The first purpose is only relevant when the directive actually has any
generic types and using a type-constructor for these cases inhibits
a type-check performance penalty, as a type-constructor's signature is
quite complex and needs to be generated for each directive.
This commit refactors the generated type-check blocks to only generate
a type-constructor call for directives that have generic types. Type
checking of inputs is achieved by generating individual statements for
all inputs, using assignments into the directive's fields.
Even if a type-constructor is used for type-inference of generic types
will the input checking also be achieved using the individual assignment
statements. This is done to support the rework of the language service,
which will start to extract symbol information from the type-check
blocks.
As a future optimization, it may be possible to reduce the number of
inputs passed into a type-constructor to only those inputs that
contribute the the type-inference of the generics. As this is not a
necessity at the moment this is left as follow-up work.
Closes#38185
PR Close#38249
"Quote expressions" are expressions that start with an identifier followed by a
comma, allowing arbitrary syntax to follow. These kinds of expressions would
throw a an error in the template type checker, which would make them hard to
track down. As quote expressions are not generally used at all, the error would
typically occur for URLs that would inadvertently occur in a binding:
```html
<a [href]="https://example.com"></a>
```
This commit lets such bindings be inferred as the `any` type.
Fixes#36568
Resolves FW-2051
PR Close#37917
In TypeScript 3.8 support was added for type-only imports, which only brings in
the symbol as a type, not their value. The Angular compiler did not yet take
the type-only keyword into account when representing symbols in type positions
as value expressions. The class metadata that the compiler emits would include
the value expression for its parameter types, generating actual imports as
necessary. For type-only imports this should not be done, as it introduces an
actual import of the module that was originally just a type-only import.
This commit lets the compiler deal with type-only imports specially, preventing
a value expression from being created.
Fixes#37900
PR Close#37912
When we were outputting class members for `setClassMetadata` calls,
we were using the string representation of the member name. This can
lead to us generating invalid code when the name contains dashes and
is quoted (e.g. `@Output() 'has-dashes' = new EventEmitter()`), because
the quotes will be stripped for the string representation.
These changes fix the issue by using the original name AST node that was
used for the declaration and which knows whether it's supposed to be
quoted or not.
Fixes#38311.
PR Close#38387
For attribute bindings that target a directive's input, the template
type checker is able to verify that the type of the input expression is
compatible with the directive's declaration for said input. This
checking adheres to the `strictNullChecks` flag as configured in the
TypeScript compilation, such that errors are reported for expressions
that include `undefined` or `null` in their type if the input's
declaration does not include those types.
There was a bug with this level of type-checking for directives that
also declare coercion members, where binding an expression that includes
the `undefined` type to a directive's input that does not include the
`undefined` type would not be reported as error.
This commit fixes the bug by changing the type-constructor in type-check
code to use an intersection type of regular inputs and coerced inputs,
instead of a union type. The union type would inadvertently allow
`undefined` types to be assigned into the regular inputs, as that would
still satisfy the characteristics of a union type.
As a result of this change, you may start to see build failures if
`strictTemplates` is enabled and `strictInputTypes` is not disabled.
These errors are legitimate and some action is required to achieve a
successful build:
1. Update the templates for which an error is reported and introduce the
non-null assertion operator at the end of the expression. This
removes the `undefined` type from the expression's type, making it
appear as a valid assignment.
2. Disable `strictNullInputTypes` in the compiler options. This will
implicitly add the non-null assertion operators similar to option 1,
but all templates in the compilation are affected.
3. Update the directive's input declaration to include the `undefined`
type, if the directive is not implemented in an external library.
PR Close#38273
Roll forward of #38147.
This allows Closure compiler to tree shake unused constructor calls to `NgModuleFactory`, which is otherwise considered
side-effectful. The Angular compiler generates factory objects which are exported but typically not used, as they are
only needed for compatibility with View Engine. This results in top-level constructor calls, such as:
```typescript
export const FooNgFactory = new NgModuleFactory(Foo);
```
`NgModuleFactory` has a side-effecting constructor, so this statement cannot be tree shaken, even if `FooNgFactory` is
never imported. The `NgModuleFactory` continues to reference its associated `NgModule` and prevents the module and all
its unused dependencies from being tree shaken, making Closure builds significantly larger than necessary.
The fix here is to wrap `NgModuleFactory` constructor with `noSideEffects(() => /* ... */)`, which tricks the Closure
compiler into assuming that the invoked function has no side effects. This allows it to tree-shake unused
`NgModuleFactory()` constructors when they aren't imported. Since the factory can be removed, the module can also be
removed (if nothing else references it), thus tree shaking unused dependencies as expected.
The one notable edge case is for lazy loaded modules. Internally, lazy loading is done as a side effect when the lazy
script is evaluated. For Angular, this side effect is registering the `NgModule`. In Ivy this is done by the
`NgModuleFactory` constructor, so lazy loaded modules **cannot** have their top-level `NgModuleFactory` constructor
call tree shaken. We handle this case by looking for the `id` field on `@NgModule` annotations. All lazy loaded modules
include an `id`. When this `id` is found, the `NgModuleFactory` is generated **without** with `noSideEffects()` call,
so Closure will not tree shake it and the module will lazy-load correctly.
PR Close#38320
This introduces a new `ModuleInfo` interface to represent some of the statically analyzed data from an `NgModule`. This
gets passed into transforms to give them more context around a given `NgModule` in the compilation.
PR Close#38320
The `TscPlugin` interface using a type of `ts.CompilerHost&Partial<UnifiedModulesHost>` for the `host` parameter
of the `wrapHost` method. However, prior to this change, the interface implementing `NgTscPlugin` class used a
type of `ts.CompilerHost&UnifiedModulesHost` for the parameter. This change corrects the inconsistency and
allows `UnifiedModulesHost` members to be optional when using the `NgtscPlugin`.
PR Close#38004
This reverts commit 7f8c2225f2.
This commit caused test failures internally, which were traced back to the
optimizer removing NgModuleFactory constructor calls when those calls caused
side-effectful registration of NgModules by their ids.
PR Close#38303
This commit disables one TypeChecker test (added as a part of
https://github.com/angular/angular/pull/38105) which make assertions about the filename while
running on Windows.
Such assertions are currently suffering from a case sensitivity issue.
PR Close#38294
This allows Closure compiler to tree shake unused constructor calls to `NgModuleFactory`, which is otherwise considered
side-effectful. The Angular compiler generates factory objects which are exported but typically not used, as they are
only needed for compatibility with View Engine. This results in top-level constructor calls, such as:
```typescript
export const FooNgFactory = new NgModuleFactory(Foo);
```
`NgModuleFactory` has a side-effecting constructor, so this statement cannot be tree shaken, even if `FooNgFactory` is
never imported. The `NgModuleFactory` continues to reference its associated `NgModule` and prevents the module and all
its unused dependencies from being tree shaken. This effectively prevents all components from being tree shaken, making
Closure builds significantly larger than they should be.
The fix here is to wrap `NgModuleFactory` constructor with `noSideEffects(() => /* ... */)`, which tricks the Closure
compiler into assuming that the invoked function has no side effects. This allows it to tree-shake unused
`NgModuleFactory()` constructors when they aren't imported. Since the factory can be removed, the module can also be
removed (if nothing else references it), thus tree shaking unused components as expected.
PR Close#38147
Large strings constants are now wrapped in a function which is called whenever used. This works around a unique
limitation of Closure, where it will **always** inline string literals at **every** usage, regardless of how large the
string literal is or how many times it is used.The workaround is to use a function rather than a string literal.
Closure has differently inlining semantics for functions, where it will check the length of the function and the number
of times it is used before choosing to inline it. By using a function, `ngtsc` makes Closure more conservative about
inlining large strings, and avoids blowing up the bundle size.This optimization is only used if the constant is a large
string. A wrapping function is not included for other use cases, since it would just increase the bundle size and add
unnecessary runtime performance overhead.
PR Close#38253
This commit adds a method `getDiagnosticsForComponent` to the
`TemplateTypeChecker`, which does the minimum amount of work to retrieve
diagnostics for a single component.
With the normal `ReusedProgramStrategy` this offers virtually no improvement
over the standard `getDiagnosticsForFile` operation, but if the
`TypeCheckingProgramStrategy` supports separate shims for each component,
this operation can yield a faster turnaround for components that are
declared in files with many other components.
PR Close#38105
Previously, a stable template id was implemented for each component in a
file. This commit adds this id to each `TemplateDiagnostic` generated from
the template type-checker, so it can potentially be used for filtration.
PR Close#38105
This commit adds an `overrideComponentTemplate` operation to the template
type-checker. This operation changes the template used during template
type-checking operations.
Overriding a template causes any previous work for it to be discarded, and
the template type-checking engine will regenerate the TCB for that template
on the next request.
This operation can be used by a consumer such as the language service to
get rapid feedback or diagnostics as the user is editing a template file,
without the need for a full incremental build iteration.
Closes#38058
PR Close#38105
Previously, the `TemplateTypeChecker` abstraction allowed fetching
diagnostics for a single file, but under the hood would generate type
checking code for the entire program to satisfy the request.
With this commit, an `OptimizeFor` hint is passed to `getDiagnosticsForFile`
which indicates whether the user intends to request diagnostics for the
whole program or is truly interested in just the single file. If the latter,
the `TemplateTypeChecker` can perform only the work needed to produce
diagnostics for just that file, thus returning answers more efficiently.
PR Close#38105
The template type-checking engine relies on the abstraction interface
`TypeCheckingProgramStrategy` to create updated `ts.Program`s for
template type-checking. The basic API is that the type-checking engine
requests changes to certain files in the program, and the strategy provides
an updated `ts.Program`.
Typically, such changes are made to 'ngtypecheck' shim files, but certain
conditions can cause template type-checking to require "inline" operations,
which change user .ts files instead. The strategy used by 'ngc' (the
`ReusedProgramStrategy`) supports these kinds of updates, but other clients
such as the language service might not always support modifying user files.
To accommodate this, the `TypeCheckingProgramStrategy` interface was
modified to include a `supportsInlineOperations` flag. If an implementation
specifies `false` for inline support, the template type-checking system will
return diagnostics on components which would otherwise require inline
operations.
Closes#38059
PR Close#38105
This commit significantly refactors the 'typecheck' package to introduce a
new abstraction, the `TemplateTypeChecker`. To achieve this:
* a 'typecheck:api' package is introduced, containing common interfaces that
consumers of the template type-checking infrastructure can depend on
without incurring a dependency on the template type-checking machinery as
a whole.
* interfaces for `TemplateTypeChecker` and `TypeCheckContext` are introduced
which contain the abstract operations supported by the implementation
classes `TemplateTypeCheckerImpl` and `TypeCheckContextImpl` respectively.
* the `TemplateTypeChecker` interface supports diagnostics on a whole
program basis to start with, but the implementation is purposefully
designed to support incremental diagnostics at a per-file or per-component
level.
* `TemplateTypeChecker` supports direct access to the type check block of a
component.
* the testing utility is refactored to be a lot more useful, and new tests
are added for the new abstraction.
PR Close#38105
Previously in the template type-checking engine, it was assumed that every
input file would have an associated type-checking shim. The type check block
code for all components in the input file would be generated into this shim.
This is fine for whole-program type checking operations, but to support the
language service's requirements for low latency, it would be ideal to be
able to check a single component in isolation, especially if the component
is declared along with many others in a single file.
This commit removes the assumption that the file/shim mapping is 1:1, and
introduces the concept of component-to-shim mapping. Any
`TypeCheckingProgramStrategy` must provide such a mapping.
To achieve this:
* type checking record information is now split into file-level data as
well as per-shim data.
* components are now assigned a stable `TemplateId` which is unique to the
file in which they're declared.
PR Close#38105
The current implementation of the TypeScriptReflectionHost does not account for members that
are string literals, i.e. `class A { 'string-literal-prop': string; }`
PR Close#38226
Prior to this commit, duplicated styles defined in multiple components in the same file were not
shared between components, thus causing extra payload size. This commit updates compiler logic to
use `ConstantPool` for the styles (while generating the `styles` array on component def), which
enables styles sharing when needed (when duplicates styles are present).
Resolves#38204.
PR Close#38213
This commit splits the transformation into 2 separate steps: Ivy compilation and actual transformation
of corresponding TS nodes. This is needed to have all `o.Expression`s generated before any TS transforms
happen. This allows `ConstantPool` to properly identify expressions that can be shared across multiple
components declared in the same file.
Resolves#38203.
PR Close#38213
In CLI v10 there was a move to use the new solution-style tsconfig
which became available in TS 3.9.
The result of this is that the standard tsconfig.json no longer contains
important information such as "paths" mappings, which ngcc might need to
correctly compute dependencies.
ngcc (and ngc and tsc) infer the path to tsconfig.json if not given an
explicit tsconfig file-path. But now that means it infers the solution
tsconfig rather than one that contains the useful information it used to
get.
This commit logs a warning in this case to inform the developer
that they might not have meant to load this tsconfig and offer
alternative options.
Fixes#36386
PR Close#38003
The `fs.relative()` method assumed that the file-system is a single tree,
which is not the case in Windows, where you can have multiple drives,
e.g. `C:`, `D:` etc.
This commit changes `fs.relative()` so that it no longer forces the result
to be a `PathSegment` and then flows that refactoring through the rest of
the compiler-cli (and ngcc). The main difference is that now, in some cases,
we needed to check whether the result is "rooted", i.e an `AbsoluteFsPath`,
rather than a `PathSegment`, before using it.
Fixes#36777
PR Close#37959
The ngtsc testing packages for file_system and logging were missing from the bazel deps rules, which means that they were not included in the releases
PR Close#37977
Incremental compilation allows for the output state of one compilation to be
reused as input to the next compilation. This involves retaining references
to instances from prior compilations, which must be done carefully to avoid
memory leaks.
This commit fixes such a leak with a complicated retention chain:
* `TrackedIncrementalBuildStrategy` unnecessarily hangs on to the previous
`IncrementalDriver` (state of the previous compilation) once the current
compilation completes.
In general this is unnecessary, but should be safe as long as the chain
only goes back one level - if the `IncrementalDriver` doesn't retain any
previous `TrackedIncrementalBuildStrategy` instances. However, this does
happen:
* `NgCompiler` indirectly causes retention of previous `NgCompiler`
instances (and thus previous `TrackedIncrementalBuildStrategy` instances)
through accidental capture of the `this` context in a closure created in
its constructor. This closure is wrapped in a `ts.ModuleResolutionCache`
used to create a `ModuleResolver` class, which is passed to the program's
`TraitCompiler` on construction.
* The `IncrementalDriver` retains a reference to the `TraitCompiler` of the
previous compilation, completing the reference chain.
The final retention chain thus looks like:
* `TrackedIncrementalBuildStrategy` of current program
* `.previous`: `IncrementalDriver` of previous program
* `.lastGood.traitCompiler`: `TraitCompiler`
* `.handlers[..].moduleResolver.moduleResolutionCache`: cache
* (via `getCanonicalFileName` closure): `NgCompiler`
* `.incrementalStrategy`: `TrackedIncrementalBuildStrategy` of previous
program.
The closure link is the "real" leak here. `NgCompiler` is creating a closure
for `getCanonicalFileName`, delegating to its
`this.adapter.getCanonicalFileName`, for the purposes of creating a
`ts.ModuleResolutionCache`. The fact that the closure references
`NgCompiler` thus eventually causes previous `NgCompiler` iterations to be
retained. This is also potentially problematic due to the shared nature of
`ts.ModuleResolutionCache`, which is potentially retained across multiple
compilations intentionally.
This commit fixes the first two links in the retention chain: the build
strategy is patched to not retain a `previous` pointer, and the `NgCompiler`
is patched to not create a closure in the first place, but instead pass a
bound function. This ensures that the `NgCompiler` does not retain previous
instances of itself in the first place, even if the build strategy does
end up retaining the previous incremental state unnecessarily.
The third link (`IncrementalDriver` unnecessarily retaining the whole
`TraitCompiler`) is not addressed in this commit as it's a more
architectural problem that will require some refactoring. However, the leak
potential of this retention is eliminated thanks to fixing the first two
issues.
PR Close#37835
This commit disables all diagnostic tests for DynamicValue diagnostics which
make assertions about the diagnostic filename while running tests on Windows.
Such assertions are currently suffering from a case sensitivity issue.
PR Close#37763
Several partial_evaluator tests in the diagnostics_spec check assert
correctness of diagnostic filenames. Previously these assertions compared
a resolved (`absoluteFrom`) filename with the TypeScript `ts.SourceFile`'s
`fileName` string, which caused the tests to fail on Windows because the
drive letter case differed.
This commit changes the assertions to use `absoluteFromSourceFile` instead
of the `fileName` string, resulting in an apples-to-apples comparison of
canonicalized paths.
PR Close#37758
This commit introduces a dedicated `DynamicValue` kind to indicate that a value
cannot be evaluated statically as the function body is not just a single return
statement. This allows more accurate reporting of why a function call failed
to be evaluated, i.e. we now include a reference to the function declaration
and have a tailor-made diagnostic message.
PR Close#37587
During AOT compilation, the value of some expressions need to be known at
compile time. The compiler has the ability to statically evaluate expressions
the best it can, but there can be occurrences when an expression cannot be
evaluated statically. For instance, the evaluation could depend on a dynamic
value or syntax is used that the compiler does not understand. Alternatively,
it is possible that an expression could be statically evaluated but the
resulting value would be of an incorrect type.
In these situations, it would be helpful if the compiler could explain why it
is unable to evaluate an expression. To this extend, the static interpreter
in Ivy keeps track of a trail of `DynamicValue`s which follow the path of nodes
that were considered all the way to the node that causes an expression to be
considered dynamic. Up until this commit, this rich trail of information was
not surfaced to a developer so the compiler was of little help to explain
why static evaluation failed, resulting in situations that are hard to debug
and resolve.
This commit adds much more insight to the diagnostic that is produced for static
evaluation errors. For dynamic values, the trail of `DynamicValue` instances
is presented to the user in a meaningful way. If a value is available but not
of the correct type, the type of the resolved value is shown.
Resolves FW-2155
PR Close#37587
Previously, an anonymous type was used for creating a diagnostic with related
information. The anonymous type would then be translated into the necessary
`ts.DiagnosticRelatedInformation` shape within `makeDiagnostic`. This commit
switches the `makeDiagnostic` signature over to taking `ts.DiagnosticRelatedInformation`
directly and introduces `makeRelatedInformation` to easily create such objects.
This is done to aid in making upcoming work more readable.
PR Close#37587
Commit 4213e8d5 introduced shim reference tagging into the compiler, and
changed how the `TypeCheckProgramHost` worked under the hood during the
creation of a template type-checking program. This work enabled a more
incremental flow for template type-checking, but unintentionally introduced
several regressions in performance, caused by poor incrementality during
`ts.Program` creation.
1. The `TypeCheckProgramHost` was made to rely on the `ts.CompilerHost` to
retrieve instances of `ts.SourceFile`s from the original program. If the
host does not return the original instance of such files, but instead
creates new instances, this has two negative effects: it incurs
additional parsing time, and it interferes with TypeScript's ability to
reuse information about such files.
2. During the incremental creation of a `ts.Program`, TypeScript compares
the `referencedFiles` of `ts.SourceFile` instances from the old program
with those in the new program. If these arrays differ, TypeScript cannot
fully reuse the old program. The implementation of reference tagging
introduced in 4213e8d5 restores the original `referencedFiles` array
after a `ts.Program` is created, which means that future incremental
operations involving that program will always fail this comparison,
effectively limiting the incrementality TypeScript can achieve.
Problem 1 exacerbates problem 2: if a new `ts.SourceFile` is created by the
host after shim generation has been disabled, it will have an untagged
`referencedFiles` array even if the original file's `referencedFiles` was
not restored, triggering problem 2 when creating the template type-checking
program.
To fix these issues, `referencedFiles` arrays are now restored on the old
`ts.Program` prior to the creation of a new incremental program. This allows
TypeScript to get the most out of reusing the old program's data.
Additionally, the `TypeCheckProgramHost` now uses the original `ts.Program`
to retrieve original instances of `ts.SourceFile`s where possible,
preventing issues when a host would otherwise return fresh instances.
Together, these fixes ensure that program reuse is as incremental as
possible, and tests have been added to verify this for certain scenarios.
An optimization was further added to prevent the creation of a type-checking
`ts.Program` in the first place if no type-checking is necessary.
PR Close#37641
Source-maps can be linked to from a source-file by a comment at
the end of the file.
Previously the `SourceFileLoader` would read
the first comment that matched `//# sourceMappingURL=` but
this is not valid since some bundlers may include embedded
source-files that contain such a comment.
Now we only look for this comment in the last non-empty line
in the file.
PR Close#32912
Previously localized strings were not mapped to their original
source location, so it was not possible to back-trace them
in tools like the i18n message extractor.
PR Close#32912
Webpack and other build tools sometimes inline the contents of the
source files in their generated source-maps, and at the same time
change the paths to be prefixed with a protocol, such as `webpack://`.
This can confuse tools that need to read these paths, so now it is
possible to provide a mapping to where these files originated.
PR Close#32912
This method will allow us to find the original location given a
generated location, which is useful in fine grained work with
source-mapping. E.g. in `$localize` tooling.
PR Close#32912
The `SourceFile` and associated code is general and reusable in
other projects (such as `@angular/localize`). Moving it to `ngtsc`
makes it more easily shared.
PR Close#37114
The `Logger` interface and its related classes are general purpose
and could be used by other tooling. Moving it into ngtsc is a more
suitable place from which to share it - similar to the FileSystem stuff.
PR Close#37114
We recently added a transformer to NGC that is responsible for downleveling Angular
decorators and constructor parameter types. The primary goal was to mitigate a
TypeScript limitation/issue that surfaces in Angular projects due to the heavy
reliance on type metadata being captured for DI. Additionally this is a pre-requisite
of making `tsickle` optional in the Angular bazel toolchain.
See: 401ef71ae5 for more context on this.
Another (less important) goal was to make sure that the CLI can re-use
this transformer for its JIT mode compilation. The CLI (as outlined in
the commit mentioned above), already has a transformer for downleveling
constructor parameters. We want to avoid this duplication and exported
the transform through the tooling-private compiler entry-point.
Early experiments in using this transformer over the current one, highlighted
that in JIT, class decorators cannot be downleveled. Angular relies on those
to be invoked immediately for JIT (so that factories etc. are generated upon loading)
The transformer we exposed, always downlevels such class decorators
though, so that would break CLI's JIT mode. We can address the CLI's
needs by adding another flag to skip class decorators. This will allow
us to continue with the goal of de-duplication.
PR Close#37545
Commit 24b2f1da2b introduced an `NgCompiler` which operates on a
`ts.Program` independently of the `NgtscProgram`. The NgCompiler got its
`IncrementalDriver` (for incremental reuse of Angular compilation results)
by looking at a monkey-patched property on the `ts.Program`.
This monkey-patching operation causes problems with the Angular indexer
(specifically, it seems to cause the indexer to retain too much of prior
programs, resulting in OOM issues). To work around this, `IncrementalDriver`
reuse is now handled by a dedicated `IncrementalBuildStrategy`. One
implementation of this interface is used by the `NgtscProgram` to perform
the old-style reuse, relying on the previous instance of `NgtscProgram`
instead of monkey-patching. Only for `NgTscPlugin` is the monkey-patching
strategy used, as the plugin sits behind an interface which only provides
access to the `ts.Program`, not a prior instance of the plugin.
PR Close#37339
Currently the partial evaluator isn't able to resolve a variable declaration that uses destructuring in the form of `const {value} = {value: 0}; const foo = value;`. These changes add some logic to allow for us to resolve the variable's value.
Fixes#36917.
PR Close#37497
Adds @nocollapse to static properties added by ngcc
iff annotateForClosureCompiler is true.
The Closure Compiler will collapse static properties
into the global namespace. Adding this annotation keeps
the properties attached to their respective object, which
allows them to be referenced via a class's constructor.
The annotation is already added by ngtsc and ngc under the
same option, this commit extends the functionality to ngcc.
Closes#36618.
PR Close#36652
In v7 of Angular we removed `tsickle` from the default `ngc` pipeline.
This had the negative potential of breaking ES2015 output and SSR due
to a limitation in TypeScript.
TypeScript by default preserves type information for decorated constructor
parameters when `emitDecoratorMetadata` is enabled. For example,
consider this snippet below:
```
@Directive()
export class MyDirective {
constructor(button: MyButton) {}
}
export class MyButton {}
```
TypeScript would generate metadata for the `MyDirective` class it has
a decorator applied. This metadata would be needed in JIT mode, or
for libraries that provide `MyDirective` through NPM. The metadata would
look as followed:
```
let MyDirective = class MyDir {}
MyDirective = __decorate([
Directive(),
__metadata("design:paramtypes", [MyButton]),
], MyDirective);
let MyButton = class MyButton {}
```
Notice that TypeScript generated calls to `__decorate` and
`__metadata`. These calls are needed so that the Angular compiler
is able to determine whether `MyDirective` is actually an directive,
and what types are needed for dependency injection.
The limitation surfaces in this concrete example because `MyButton`
is declared after the `__metadata(..)` call, while `__metadata`
actually directly references `MyButton`. This is illegal though because
`MyButton` has not been declared at this point. This is due to the
so-called temporal dead zone in JavaScript. Errors like followed will
be reported at runtime when such file/code evaluates:
```
Uncaught ReferenceError: Cannot access 'MyButton' before initialization
```
As noted, this is a TypeScript limitation because ideally TypeScript
shouldn't evaluate `__metadata`/reference `MyButton` immediately.
Instead, it should defer the reference until `MyButton` is actually
declared. This limitation will not be fixed by the TypeScript team
though because it's a limitation as per current design and they will
only revisit this once the tc39 decorator proposal is finalized
(currently stage-2 at time of writing).
Given this wontfix on the TypeScript side, and our heavy reliance on
this metadata in libraries (and for JIT mode), we intend to fix this
from within the Angular compiler by downleveling decorators to static
properties that don't need to evaluate directly. For example:
```
MyDirective.ctorParameters = () => [MyButton];
```
With this snippet above, `MyButton` is not referenced directly. Only
lazily when the Angular runtime needs it. This mitigates the temporal
dead zone issue caused by a limitation in TypeScript's decorator
metadata output. See: https://github.com/microsoft/TypeScript/issues/27519.
In the past (as noted; before version 7), the Angular compiler by
default used tsickle that already performed this transformation. We
moved the transformation to the CLI for JIT and `ng-packager`, but now
we realize that we can move this all to a single place in the compiler
so that standalone ngc consumers can benefit too, and that we can
disable tsickle in our Bazel `ngc-wrapped` pipeline (that currently
still relies on tsickle to perform this decorator processing).
This transformation also has another positive side-effect of making
Angular application/library code more compatible with server-side
rendering. In principle, TypeScript would also preserve type information
for decorated class members (similar to how it did that for constructor
parameters) at runtime. This becomes an issue when your application
relies on native DOM globals for decorated class member types. e.g.
```
@Input() panelElement: HTMLElement;
```
Your application code would then reference `HTMLElement` directly
whenever the source file is loaded in NodeJS for SSR. `HTMLElement`
does not exist on the server though, so that will become an invalid
reference. One could work around this by providing global mocks for
these DOM symbols, but that doesn't match up with other places where
dependency injection is used for mocking DOM/browser specific symbols.
More context in this issue: #30586. The TL;DR here is that the Angular
compiler does not care about types for these class members, so it won't
ever reference `HTMLElement` at runtime.
Fixes#30106. Fixes#30586. Fixes#30141.
Resolves FW-2196. Resolves FW-2199.
PR Close#37382
The new tooling-cli-shared-api is used to guard changes to packages/compiler-cli/src/tooling.ts
which is a private API sharing channel between Angular FW and CLI.
Changes to this file should be rare and explicitly approved by at least two members
of the CLI team.
PR Close#37467
`NgCompiler` is the heart of ngtsc and can be used to analyze and compile
Angular programs in a variety of environments. Most of these integrations
rely on `NgProgram` and the creation of an `NgCompilerHost` in order to
create a `ts.Program` with the right shape for `NgCompiler`.
However, certain environments (such as the Angular Language Service) have
their own mechanisms for creating `ts.Program`s that don't make use of a
`ts.CompilerHost`. In such environments, an `NgCompilerHost` does not make
sense.
This commit breaks the dependency of `NgCompiler` on `NgCompilerHost` and
extracts the specific interface of the host on which `NgCompiler` depends
into a new interface, `NgCompilerAdapter`. This interface includes methods
from `ts.CompilerHost`, the `ExtendedTsCompilerHost`, as well as APIs from
`NgCompilerHost`.
A consumer such as the language service can implement this API without
needing to jump through hoops to create an `NgCompilerHost` implementation
that somehow wraps its specific environment.
PR Close#37118
When the compiler encounters a function call within an NgModule imports
section, it attempts to resolve it to an NgModule-annotated class by
looking at the function body and evaluating the statements there. This
evaluation can only understand simple functions which have a single
return statement as their body. If the function the user writes is more
complex than that, the compiler won't be able to understand it and
previously the PartialEvaluator would return a "DynamicValue" for
that import.
With this change, in the event the function body resolution fails the
PartialEvaluator will now attempt to use its foreign function resolvers to
determine the correct result from the function's type signtaure instead. If
the function is annotated with a correct ModuleWithProviders type, the
compiler will be able to understand the import without static analysis of
the function body.
PR Close#37126
The work to support case-sensitivity in the `FileSystem` went too far
with the `LogicalFileSystem`, which is used to compute import paths
that will be added to files processed by ngtsc and ngcc.
Previously all logical paths were canonicalised, which meant that on
case-insensitive file-systems, the paths were all set to lower case.
This resulted in incorrect imports being added to files. For example:
```
import { Apollo } from './Apollo';
import { SelectPipe } from './SelectPipe';
import * as ɵngcc0 from '@angular/core';
import * as ɵngcc1 from './selectpipe';
```
The import from `./SelectPipe` is from the original file, while the
import from `./selectpipe` is added by ngcc. This causes the
TypeScript compiler to complain, or worse for paths not to be
matched correctly.
Now, when computing logical paths, the original absolute paths
are matched against rootDirs in a canonical manner, but the actual
logical path that is returned maintains it original casing.
Fixes#36992, #36993, #37000
PR Close#37008
With this change we drop support for TypeScript 3.8 and remove all related tests.
BREAKING CHANGE:
TypeScript 3.8 is no longer supported, please update to TypeScript 3.9.
PR Close#37129
In some versions of TypeScript, the transformation of synthetic
`$localize` tagged template literals is broken.
See https://github.com/microsoft/TypeScript/issues/38485
We now compute what the expected final output target of the
compilation will be so that we can generate ES5 compliant
`$localize` calls instead of relying upon TS to do the downleveling
for us.
This is a workaround for the TS compiler bug, which could be removed
when this is fixed. But since it only affects ES5 targeted compilations,
which is now not the norm, it has limited impact on the majority of
Angular projects. So this fix can probably be left in indefinitely.
PR Close#36989
The previous implementations of `hasBaseClass()` are almost
identical to the implementation of `getBaseClassExpression()`.
There is little benefit in duplicating this code so this refactoring
changes `hasBaseClass()` to just call `getBaseClassExpression()`.
This allows the various hosts that implement this to be simplified.
PR Close#36989
The comment in this function confused me, so I updated it to clarify that
`isClass()` is not true for un-named classes.
Also, I took the opportunity to use a helper method to simplify the function
itself.
PR Close#36989
Adding `readFileBuffer()` method and allowing `writeFile()` to accept a
Buffer object will be useful when reading and writing non-text files,
such as is done in the `@angular/localize` package.
PR Close#36843
ASTs for property read and method calls contain information about
the entire span of the expression, including its receiver. Use cases
like a language service and compile error messages may be more
interested in the span of the direct identifier for which the
expression is constructed (i.e. an accessed property). To support this,
this commit adds a `nameSpan` property on
- `PropertyRead`s
- `SafePropertyRead`s
- `PropertyWrite`s
- `MethodCall`s
- `SafeMethodCall`s
The `nameSpan` property already existed for `BindingPipe`s.
This commit also updates usages of these expressions' `sourceSpan`s in
Ngtsc and the langauge service to use `nameSpan`s where appropriate.
PR Close#36826
Some projects include .js source files (via the TypeScript allowJs option).
Previously, the compiler would attempt to tag these files for shims, which
caused errors as the regex used to create shim filenames assumes a .ts file.
This commit fixes the bug by filtering out non-ts files during tagging.
PR Close#36987
These tests were matching file-paths against what is retrieved from the
TS compiler. But the TS compiler paths have been canonicalised, so the
tests were brittle on case-insensitive file-systems.
PR Close#36859
These tests were matching file-paths against what is retrieved from the
TS compiler. But the TS compiler paths have been canonicalised, so the
tests were brittle on case-insensitive file-systems.
PR Close#36859
These tests were matching file-paths against what is retrieved from the
TS compiler. But the TS compiler paths have been canonicalised, so the
tests were brittle on case-insensitive file-systems.
PR Close#36859
The type checking infrastrure uses file-paths that may come from the
TS compiler. Such paths will have been canonicalized, and so the type
checking classes must also canonicalize paths when matching.
PR Close#36859
Since the `MockFileSystemWindows` is case-insensitive, any
drive path that must be added to a normalized path should be lower
case to make the path canonical.
PR Close#36859
Previously this class used the file passed in directly to look up files in the
in-memory mock file-system. But this doesn't match the behaviour of
case-insensitive file-systems. Now the look up is done on the canonical
file paths.
PR Close#36859
Previously this method was returning the exact opposite value
than the correct one.
Also, calling `this.exists()` causes an infinite recursions,
so the actual file-system `fs.existsSync()` method is used
to ascertain the case-sensitivity of the file-system.
PR Close#36859
Previously the `getRootDirs()` function was not converting
the root directory paths to their canonical form, which can
cause problems on case-insensitive file-systems.
PR Close#36859
The `getCanonicalFileName()` method was not actually
calling the `useCaseSensitiveFileNames()` method. So
it always returned a case-sensitive canonical filename.
PR Close#36859
Previously in v9, we deprecated the pattern of undecorated base classes
that rely on Angular features. We ran a migration for this in version 9
and will run the same on in version 10 again.
To ensure that projects do not regress and start using the unsupported
pattern again, we report an error in ngtsc if such undecorated classes
are discovered.
We keep the compatibility code enabled in ngcc so that libraries
can be still be consumed, even if they have not been migrated yet.
Resolves FW-2130.
PR Close#36921
This optimization builds on a lot of prior work to finally make type-
checking of templates incremental.
Incrementality requires two main components:
- the ability to reuse work from a prior compilation.
- the ability to know when changes in the current program invalidate that
prior work.
Prior to this commit, on every type-checking pass the compiler would
generate new .ngtypecheck files for each original input file in the program.
1. (Build #1 main program): empty .ngtypecheck files generated for each
original input file.
2. (Build #1 type-check program): .ngtypecheck contents overridden for those
which have corresponding components that need type-checked.
3. (Build #2 main program): throw away old .ngtypecheck files and generate
new empty ones.
4. (Build #2 type-check program): same as step 2.
With this commit, the `IncrementalDriver` now tracks template type-checking
_metadata_ for each input file. The metadata contains information about
source mappings for generated type-checking code, as well as some
diagnostics which were discovered at type-check analysis time. The actual
type-checking code is stored in the TypeScript AST for type-checking files,
which is now re-used between programs as follows:
1. (Build #1 main program): empty .ngtypecheck files generated for each
original input file.
2. (Build #1 type-check program): .ngtypecheck contents overridden for those
which have corresponding components that need type-checked, and the
metadata registered in the `IncrementalDriver`.
3. (Build #2 main program): The `TypeCheckShimGenerator` now reuses _all_
.ngtypecheck `ts.SourceFile` shims from build #1's type-check program in
the construction of build #2's main program. Some of the contents of
these files might be stale (if a component's template changed, for
example), but wholesale reuse here prevents unnecessary changes in the
contents of the program at this point and makes TypeScript's job a lot
easier.
4. (Build #2 type-check program): For those input files which have not
"logically changed" (meaning components within are semantically the same
as they were before), the compiler will re-use the type-check file
metadata from build #1, and _not_ generate a new .ngtypecheck shim.
For components which have logically changed or where the previous
.ngtypecheck contents cannot otherwise be reused, code generation happens
as before.
PR Close#36211
As a performance optimization, this commit splits the single
__ngtypecheck__.ts file which was previously added to the user's program as
a container for all template type-checking code into multiple .ngtypecheck
shim files, one for each original file in the user's program.
In larger applications, the generation, parsing, and checking of this single
type-checking file was a huge performance bottleneck, with the file often
exceeding 1 MB in text content. Particularly in incremental builds,
regenerating this single file for the entire application proved especially
expensive.
This commit introduces a new strategy for template type-checking code which
makes use of a new interface, the `TypeCheckingProgramStrategy`. This
interface abstracts the process of creating a new `ts.Program` to type-check
a particular compilation, and allows the mechanism there to be kept separate
from the more complex logic around dealing with multiple .ngtypecheck files.
A new `TemplateTypeChecker` hosts that logic and interacts with the
`TypeCheckingProgramStrategy` to actually generate and return diagnostics.
The `TypeCheckContext` class, previously the workhorse of template type-
checking, is now solely focused on collecting and generating type-checking
file contents.
A side effect of implementing the new `TypeCheckingProgramStrategy` in this
way is that the API is designed to be suitable for use by the Angular
Language Service as well. The LS also needs to type-check components, but
has its own method for constructing a `ts.Program` with type-checking code.
Note that this commit does not make the actual checking of templates at all
_incremental_ just yet. That will happen in a future commit.
PR Close#36211
Shim generation was built on a lie.
Shims are files added to the program which aren't original files authored by
the user, but files authored effectively by the compiler. These fall into
two categories: files which will be generated (like the .ngfactory shims we
generate for View Engine compatibility) as well as files used internally in
compilation (like the __ng_typecheck__.ts file).
Previously, shim generation was driven by the `rootFiles` passed to the
compiler as input. These are effectively the `files` listed in the
`tsconfig.json`. Each shim generator (e.g. the `FactoryGenerator`) would
examine the `rootFiles` and produce a list of shim file names which it would
be responsible for generating. These names would then be added to the
`rootFiles` when the program was created.
The fatal flaw here is that `rootFiles` does not always account for all of
the files in the program. In fact, it's quite rare that it does. Users don't
typically specify every file directly in `files`. Instead, they rely on
TypeScript, during program creation, starting with a few root files and
transitively discovering all of the files in the program.
This happens, however, during `ts.createProgram`, which is too late to add
new files to the `rootFiles` list.
As a result, shim generation was only including shims for files actually
listed in the `tsconfig.json` file, and not for the transitive set of files
in the user's program as it should.
This commit completely rewrites shim generation to use a different technique
for adding files to the program, inspired by View Engine's shim generator.
In this new technique, as the program is being created and `ts.SourceFile`s
are being requested from the `NgCompilerHost`, shims for those files are
generated and a reference to them is patched onto the original file's
`ts.SourceFile.referencedFiles`. This causes TS to think that the original
file references the shim, and causes the shim to be included in the program.
The original `referencedFiles` array is saved and restored after program
creation, hiding this little hack from the rest of the system.
The new shim generation engine differentiates between two kinds of shims:
top-level shims (such as the flat module entrypoint file and
__ng_typecheck__.ts) and per-file shims such as ngfactory or ngsummary
files. The former are included via `rootFiles` as before, the latter are
included via the `referencedFiles` of their corresponding original files.
As a result of this change, shims are now correctly generated for all files
in the program, not just the ones named in `tsconfig.json`.
A few mitigating factors prevented this bug from being realized until now:
* in g3, `files` does include the transitive closure of files in the program
* in CLI apps, shims are not really used
This change also makes use of a novel technique for associating information
with source files: the use of an `NgExtension` `Symbol` to patch the
information directly onto the AST object. This is used in several
circumstances:
* For shims, metadata about a `ts.SourceFile`'s status as a shim and its
origins are held in the extension data.
* For original files, the original `referencedFiles` are stashed in the
extension data for later restoration.
The main benefit of this technique is a lot less bookkeeping around `Map`s
of `ts.SourceFile`s to various kinds of data, which need to be tracked/
invalidated as part of incremental builds.
This technique is based on designs used internally in the TypeScript
compiler and is serving as a prototype of this design in ngtsc. If it works
well, it could have benefits across the rest of the compiler.
PR Close#36211
The compiler needs to track the dependencies of a component, including any
NgModules which happen to be present in a component's scope. If an upstream
NgModule changes, any downstream components need to have their templates
re-compiled and re-typechecked.
Previously, the compiler handled this well for the A -> B -> C case where
module A imports module B which re-exports module C. However, it fell apart
in the A -> B -> C -> D case, because previously tracking focused on changes
to components/directives in the scope, and not NgModules specifically.
This commit introduces logic to track which NgModules contributed to a given
scope, and treat them as dependencies of any components within.
This logic also contains a bug, which is intentional for now. It
purposefully does not track transitive dependencies of the NgModules which
contribute to a scope. If it did, using the current dependency system, this
would treat all components and directives (even those not exported into the
scope) as dependencies, causing a major performance bottleneck. Only those
dependencies which contributed to the module's export scope should be
considered, but the current system is incapable of making this distinction.
This will be fixed at a later date.
PR Close#36211
Remove TypeScript 3.6 and 3.7 support from Angular along with tests that
ensure those TS versions work.
BREAKING CHANGE: typescript 3.6 and 3.7 are no longer supported, please
update to typescript 3.8
PR Close#36329
An enum declaration in TypeScript code will be emitted into JavaScript
as a regular variable declaration, with the enum members being declared
inside an IIFE. For ngcc to support interpreting such variable
declarations as enum declarations with its members, ngcc needs to
recognize the enum declaration emit structure and extract all member
from the statements in the IIFE.
This commit extends the `ConcreteDeclaration` structure in the
`ReflectionHost` abstraction to be able to capture the enum members
on a variable declaration, as a substitute for the original
`ts.EnumDeclaration` as it existed in TypeScript code. The static
interpreter has been extended to handle the extracted enum members
as it would have done for `ts.EnumDeclaration`.
Fixes#35584
Resolves FW-2069
PR Close#36550
The html parser already normalizes line endings (converting `\r\n` to `\n`)
for most text in templates but it was missing the expressions of ICU expansions.
In ViewEngine backticked literal strings, used to define inline templates,
were already normalized by the TypeScript parser.
In Ivy we are parsing the raw text of the source file directly so the line
endings need to be manually normalized.
This change ensures that inline templates have the line endings of ICU
expression normalized correctly, which matches the ViewEngine.
In ViewEngine external templates, defined in HTML files, the behavior was
different, since TypeScript was not normalizing the line endings.
Specifically, ICU expansion "expressions" are not being normalized.
This is a problem because it means that i18n message ids can be different on
different machines that are setup with different line ending handling,
or if the developer moves a template from inline to external or vice versa.
The goal is always to normalize line endings, whether inline or external.
But this would be a breaking change since it would change i18n message ids
that have been previously computed. Therefore this commit aligns the ivy
template parsing to have the same "buggy" behavior for external templates.
There is now a compiler option `i18nNormalizeLineEndingsInICUs`, which
if set to `true` will ensure the correct non-buggy behavior. For the time
being this option defaults to `false` to ensure backward compatibility while
allowing opt-in to the desired behavior. This option's default will be
flipped in a future breaking change release.
Further, when this option is set to `false`, any ICU expression tokens,
which have not been normalized, are added to the `ParseResult` from the
`HtmlParser.parse()` method. In the future, this collection of tokens could
be used to diagnose and encourage developers to migrate their i18n message
ids. See FW-2106.
Closes#36725
PR Close#36741
When the compiler needs to convert a type reference to a value
expression, it may encounter a type that refers to a namespaced symbol.
Such namespaces need to be handled specially as there's various forms
available. Consider a namespace named "ns":
1. One can refer to a namespace by itself: `ns`. A namespace is only
allowed to be used in a type position if it has been merged with a
class, but even if this is the case it may not be possible to convert
that type into a value expression depending on the import form. More
on this later (case a below)
2. One can refer to a type within the namespace: `ns.Foo`. An import
needs to be generated to `ns`, from which the `Foo` property can then
be read.
3. One can refer to a type in a nested namespace within `ns`:
`ns.Foo.Bar` and possibly even deeper nested. The value
representation is similar to case 2, but includes additional property
accesses.
The exact strategy of how to deal with these cases depends on the type
of import used. There's two flavors available:
a. A namespaced import like `import * as ns from 'ns';` that creates
a local namespace that is irrelevant to the import that needs to be
generated (as said import would be used instead of the original
import).
If the local namespace "ns" itself is referred to in a type position,
it is invalid to convert it into a value expression. Some JavaScript
libraries publish a value as default export using `export = MyClass;`
syntax, however it is illegal to refer to that value using "ns".
Consequently, such usage in a type position *must* be accompanied by
an `@Inject` decorator to provide an explicit token.
b. An explicit namespace declaration within a module, that can be
imported using a named import like `import {ns} from 'ns';` where the
"ns" module declares a namespace using `declare namespace ns {}`.
In this case, it's the namespace itself that needs to be imported,
after which any qualified references into the namespace are converted
into property accesses.
Before this change, support for namespaces in the type-to-value
conversion was limited and only worked correctly for a single qualified
name using a namespace import (case 2a). All other cases were either
producing incorrect code or would crash the compiler (case 1a).
Crashing the compiler is not desirable as it does not indicate where
the issue is. Moreover, the result of a type-to-value conversion is
irrelevant when an explicit injection token is provided using `@Inject`,
so referring to a namespace in a type position (case 1) could still be
valid.
This commit introduces logic to the type-to-value conversion to be able
to properly deal with all type references to namespaced symbols.
Fixes#36006
Resolves FW-1995
PR Close#36106
1. update jasmine to 3.5
2. update @types/jasmine to 3.5
3. update @types/jasminewd2 to 2.0.8
Also fix several cases, the new jasmine 3 will help to create test cases correctly,
such as in the `jasmine 2.x` version, the following case will pass
```
expect(1 == 2);
```
But in jsamine 3, the case will need to be
```
expect(1 == 2).toBeTrue();
```
PR Close#34625
During static evaluation of expressions, the partial evaluator
may come across a binary + operator for which it needs to
evaluate its operands. Any of these operands may be a reference
to an enum member, in which case the enum member's value needs
to be used as literal value, not the enum member reference
itself. This commit fixes the behavior by resolving an
`EnumValue` when used as a literal value.
Fixes#35584
Resolves FW-1951
PR Close#36461
Previously, `isRelativePath()` assumed paths are *nix-style. This caused
Windows-style paths (such as `C:\foo\some-package\some-file.js`) to not
be recognized as "relative" imports.
This commit fixes this by using the OS-agnostic `isRooted()` helper and
also accounting for both styles of path delimiters: `/` and `\`
PR Close#36372
In Ivy, Angular decorators are compiled into static fields that are
inserted into a class declaration in a TypeScript transform. When
targeting Closure compiler such fields need to be annotated with
`@nocollapse` to prevent them from being lifted from a static field into
a variable, as that would prevent the Ivy runtime from being able to
find the compiled definitions.
Previously, there was a bug in TypeScript where synthetic comments added
in a transform would not be emitted at all, so as a workaround a global
regex-replace was done in the emit's `writeFile` callback that would add
the `@nocollapse` annotation to all static Ivy definition fields. This
approach is no longer possible when ngtsc is running as TypeScript
plugin, as a plugin cannot control emit behavior.
The workaround is no longer necessary, as synthetic comments are now
properly emitted, likely as of
https://github.com/microsoft/TypeScript/pull/22141 which has been
released with TypeScript 2.8.
This change is required for running ngtsc as TypeScript plugin in
Bazel's `ts_library` rule, to move away from the custom `ngc_wrapped`
approach.
Resolves FW-1952
PR Close#35932
This commit augments the `FactoryDef` declaration of Angular decorated
classes to contain information about the parameter decorators used in
the constructor. If no constructor is present, or none of the parameters
have any Angular decorators, then this will be represented using the
`null` type. Otherwise, a tuple type is used where the entry at index `i`
corresponds with parameter `i`. Each tuple entry can be one of two types:
1. If the associated parameter does not have any Angular decorators,
the tuple entry will be the `null` type.
2. Otherwise, a type literal is used that may declare at least one of
the following properties:
- "attribute": if `@Attribute` is present. The injected attribute's
name is used as string literal type, or the `unknown` type if the
attribute name is not a string literal.
- "self": if `@Self` is present, always of type `true`.
- "skipSelf": if `@SkipSelf` is present, always of type `true`.
- "host": if `@Host` is present, always of type `true`.
- "optional": if `@Optional` is present, always of type `true`.
A property is only present if the corresponding decorator is used.
Note that the `@Inject` decorator is currently not included, as it's
non-trivial to properly convert the token's value expression to a
type that is valid in a declaration file.
Additionally, the `ComponentDefWithMeta` declaration that is created for
Angular components has been extended to include all selectors on
`ng-content` elements within the component's template.
This additional metadata is useful for tooling such as the Angular
Language Service, as it provides the ability to offer suggestions for
directives/components defined in libraries. At the moment, such
tooling extracts the necessary information from the _metadata.json_
manifest file as generated by ngc, however this metadata representation
is being replaced by the information emitted into the declaration files.
Resolves FW-1870
PR Close#35695
Currently, when Angular code is built with Bazel and with Ivy, generated
factory shims (.ngfactory files) are not processed via the majority of
tsickle's transforms. This is a subtle effect of the build infrastructure,
but it boils down to a TsickleHost method `shouldSkipTsickleProcessing`.
For ngc_wrapped builds (Bazel + Angular), this method is defined in the
`@bazel/typescript` (aka bazel rules_typescript) implementation of
`CompilerHost`. The default behavior is to skip tsickle processing for files
which are not present in the original `srcs[]` of the build rule. In
Angular's case, this includes all generated shim files.
For View Engine factories this is probably desirable as they're quite
complex and they've never been tested with tsickle. Ivy factories however
are smaller and very straightforward, and it makes sense to treat them like
any other output.
This commit adjusts two independent implementations of
`shouldSkipTsickleProcessing` to enable transformation of Ivy shims:
* in `@angular/bazel` aka ngc_wrapped, the upstream `@bazel/typescript`
`CompilerHost` is patched to treat .ngfactory files the same as their
original source file, with respect to tsickle processing.
It is currently not possible to test this change as we don't have any test
that inspects tsickle output with bazel. It will be extensively tested in
g3.
* in `ngc`, Angular's own implementation is adjusted to allow for the
processing of shims when compiling with Ivy. This enables a unit test to
be written to validate the correct behavior of tsickle when given a host
that's appropriately configured to process factory shims.
For ngtsc-as-a-plugin, a similar fix will need to be submitted upstream in
tsc_wrapped.
PR Close#35848
PR Close#35975
This commit adds support in the Angular monorepo and in the Angular
compiler(s) for TypeScript 3.8. All packages can now compile with
TS 3.8.
For most of the repo, only a handful few typings adjustments were needed:
* TS 3.8 has a new `CustomElementConstructor` DOM type, which enforces a
zero-argument constructor. The `NgElementConstructor` type previously
declared a required `injector` argument despite the fact that its
implementation allowed `injector` to be optional. The interface type was
updated to reflect the optionality of the argument.
* Certain error messages were changed, and expectations in tests were
updated as a result.
* tsserver (part of language server) now returns performance information in
responses, so test expectations were changed to only assert on the actual
body content of responses.
For compiler-cli and schematics (which use the TypeScript AST) a major
breaking change was the introduction of the export form:
```typescript
export * as foo from 'bar';
```
This is a `ts.NamespaceExport`, and the `exportClause` of a
`ts.ExportDeclaration` can now take this type as well as `ts.NamedExports`.
This broke a lot of places where `exportClause` was assumed to be
`ts.NamedExports`.
For the most part these breakages were in cases where it is not necessary
to handle the new `ts.NamedExports` anyway. ngtsc's design uses the
`ts.TypeChecker` APIs to understand syntax and so automatically supports the
new form of exports.
The View Engine compiler on the other hand extracts TS structures into
metadata.json files, and that format was not designed for namespaced
exports. As a result it will take a nontrivial amount of work if we want to
support such exports in View Engine. For now, these new exports are not
accounted for in metadata.json, and so using them in "folded" Angular
expressions will result in errors (probably claiming that the referenced
exported namespace doesn't exist).
Care was taken to only use TS APIs which are present in 3.7/3.6, as Angular
needs to remain compatible with these for the time being.
This commit does not update angular.io.
PR Close#35864
Prior to this commit, while calculating the scope for a module, Ivy compiler processed `declarations` field first and `imports` after that. That results in a couple issues:
* for Pipes with the same `name` and present in `declarations` and in an imported module, Pipe from imported module was selected. In View Engine the logic is opposite: Pipes from `declarations` field receive higher priority.
* for Directives with the same selector and present in `declarations` and in an imported module, we first invoked the logic of a Directive from `declarations` field and after that - imported Directive logic. In View Engine, it was the opposite and the logic of a Directive from the `declarations` field was invoked last.
In order to align Ivy and View Engine behavior, this commit updates the logic in which we populate module scope: we first process all imports and after that handle `declarations` field. As a result, in Ivy both use-cases listed above work similar to View Engine.
Resolves#35502.
PR Close#35850
This commit splits the ngtsc `core` package's api entrypoint, which
previously was a single `api.ts` file, into an api/ directory with multiple
files. This is done to isolate the parts of the API definitions pertaining
to the public-facing `angularCompilerOptions` field in tsconfig.json into a
single file, which will enable a public API guard test to be added in a
future commit.
PR Close#35885
Currently, when Angular code is built with Bazel and with Ivy, generated
factory shims (.ngfactory files) are not processed via the majority of
tsickle's transforms. This is a subtle effect of the build infrastructure,
but it boils down to a TsickleHost method `shouldSkipTsickleProcessing`.
For ngc_wrapped builds (Bazel + Angular), this method is defined in the
`@bazel/typescript` (aka bazel rules_typescript) implementation of
`CompilerHost`. The default behavior is to skip tsickle processing for files
which are not present in the original `srcs[]` of the build rule. In
Angular's case, this includes all generated shim files.
For View Engine factories this is probably desirable as they're quite
complex and they've never been tested with tsickle. Ivy factories however
are smaller and very straightforward, and it makes sense to treat them like
any other output.
This commit adjusts two independent implementations of
`shouldSkipTsickleProcessing` to enable transformation of Ivy shims:
* in `@angular/bazel` aka ngc_wrapped, the upstream `@bazel/typescript`
`CompilerHost` is patched to treat .ngfactory files the same as their
original source file, with respect to tsickle processing.
It is currently not possible to test this change as we don't have any test
that inspects tsickle output with bazel. It will be extensively tested in
g3.
* in `ngc`, Angular's own implementation is adjusted to allow for the
processing of shims when compiling with Ivy. This enables a unit test to
be written to validate the correct behavior of tsickle when given a host
that's appropriately configured to process factory shims.
For ngtsc-as-a-plugin, a similar fix will need to be submitted upstream in
tsc_wrapped.
PR Close#35848
It's an error to declare a variable twice on a specific template:
```html
<div *ngFor="let i of items; let i = index">
</div>
```
This commit introduces a template type-checking error which helps to detect
and diagnose this problem.
Fixes#35186
PR Close#35674
For view and content queries, the Ivy compiler attempts to statically
evaluate the predicate token so that string predicates containing
comma-separated reference names can be split into an array of strings
during compilation. When the predicate is a dynamic value that cannot be
statically interpreted at compile time, the compiler would previously
produce an error. This behavior breaks a use-case where an `InjectionToken`
is being used as query predicate, as the usage of the `new` keyword
prevents such predicates from being statically evaluated.
This commit changes the behavior to no longer produce an error for
dynamic values. Instead, the expression is emitted as is into the
generated code, postponing the evaluation to happen at runtime.
Fixes#34267
Resolves FW-1828
PR Close#35307
It's possible to pass a directive as an input to itself. Consider:
```html
<some-cmp #ref [value]="ref">
```
Since the template type-checker attempts to infer a type for `<some-cmp>`
using the values of its inputs, this creates a circular reference where the
type of the `value` input is used in its own inference:
```typescript
var _t0 = SomeCmp.ngTypeCtor({value: _t0});
```
Obviously, this doesn't work. To resolve this, the template type-checker
used to generate a `null!` expression when a reference would otherwise be
circular:
```typescript
var _t0 = SomeCmp.ngTypeCtor({value: null!});
```
This effectively asks TypeScript to infer a value for this context, and
works well to resolve this simple cycle. However, if the template
instead tries to use the circular value in a larger expression:
```html
<some-cmp #ref [value]="ref.prop">
```
The checker would generate:
```typescript
var _t0 = SomeCmp.ngTypeCtor({value: (null!).prop});
```
In this case, TypeScript can't figure out any way `null!` could have a
`prop` key, and so it infers `never` as the type. `(never).prop` is thus a
type error.
This commit implements a better fallback pattern for circular references to
directive types like this. Instead of generating a `null!` in place for the
reference, a type is inferred by calling the type constructor again with
`null!` as its input. This infers the widest possible type for the directive
which is then used to break the cycle:
```typescript
var _t0 = SomeCmp.ngTypeCtor(null!);
var _t1 = SomeCmp.ngTypeCtor({value: _t0.prop});
```
This has the desired effect of validating that `.prop` is legal for the
directive type (the type of `#ref`) while also avoiding a cycle.
Fixes#35372Fixes#35603Fixes#35522
PR Close#35622
NG6002/NG6003 are errors produced when an NgModule being compiled has an
imported or exported type which does not have the proper metadata (that is,
it doesn't appear to be an @NgModule, or @Directive, etc. depending on
context).
Previously this error message was a bit sparse. However, Github issues show
that this is the most common error users receive when for whatever reason
ngcc wasn't able to handle one of their libraries, or they just didn't run
it. So this commit changes the error message to offer a bit more useful
context, instructing users differently depending on whether the class in
question is from their own project, from NPM, or from a monorepo-style local
dependency.
PR Close#35620
Under View Engine's default (non-fullTemplateTypeCheck) checking, object and
array literals which appear in templates are treated as having type `any`.
This allows a number of patterns which would not otherwise compile, such as
indexing an object literal by a string:
```html
{{ {'a': 1, 'b': 2}[value] }}
```
(where `value` is `string`)
Ivy, meanwhile, has always inferred strong types for object literals, even
in its compatibility mode. This commit fixes the bug, and adds the
`strictLiteralTypes` flag to specifically control this inference. When the
flag is `false` (in compatibility mode), object and array literals receive
the `any` type.
PR Close#35462
In its default compatibility mode, the Ivy template type-checker attempts to
emulate the View Engine default mode as accurately as is possible. This
commit addresses a gap in this compatibility that stems from a View Engine
type-checking bug.
Consider two template expressions:
```html
{{ obj?.field }}
{{ fn()?.field }}
```
and suppose that the type of `obj` and `fn()` are the same - both return
either `null` or an object with a `field` property.
Under View Engine, these type-check differently. The `obj` case will catch
if the object type (when not null) does not have a `field` property, while
the `fn()` case will not. This is due to how View Engine represents safe
navigations:
```typescript
// for the 'obj' case
(obj == null ? null as any : obj.field)
// for the 'fn()' case
let tmp: any;
((tmp = fn()) == null ? null as any : tmp.field)
```
Because View Engine uses the same code generation backend as it does to
produce the runtime code for this expression, it uses a ternary for safe
navigation, with a temporary variable to avoid invoking 'fn()' twice. The
type of this temporary variable is 'any', however, which causes the
`tmp.field` check to be meaningless.
Previously, the Ivy template type-checker in compatibility mode assumed that
`fn()?.field` would always check for the presence of 'field' on the non-null
result of `fn()`. This commit emulates the View Engine bug in Ivy's
compatibility mode, so an 'any' type will be inferred under the same
conditions.
As part of this fix, a new format for safe navigation operations in template
type-checking code is introduced. This is based on the realization that
ternary based narrowing is unnecessary.
For the `fn()` case in strict mode, Ivy now generates:
```typescript
(null as any ? fn()!.field : undefined)
```
This effectively uses the ternary operator as a type "or" operation. The
resulting type will be a union of the type of `fn()!.field` with
`undefined`.
For the `fn()` case in compatibility mode, Ivy now emulates the bug with:
```typescript
(fn() as any).field
```
The cast expression includes the call to `fn()` and allows it to be checked
while still returning a type of `any` from the expression.
For the `obj` case in compatibility mode, Ivy now generates:
```typescript
(obj!.field as any)
```
This cast expression still returns `any` for its type, but will check for
the existence of `field` on the type of `obj!`.
PR Close#35462
In ES5 code, TypeScript requires certain helpers (such as
`__spreadArrays()`) to be able to support ES2015+ features. These
helpers can be either imported from `tslib` (by setting the
`importHelpers` TS compiler option to `true`) or emitted inline (by
setting the `importHelpers` and `noEmitHelpers` TS compiler options to
`false`, which is the default value for both).
Ngtsc's `StaticInterpreter` (which is also used during ngcc processing)
is able to statically evaluate some of these helpers (currently
`__assign()`, `__spread()` and `__spreadArrays()`), as long as
`ReflectionHost#getDefinitionOfFunction()` correctly detects the
declaration of the helper. For this to happen, the left-hand side of the
corresponding call expression (i.e. `__spread(...)` or
`tslib.__spread(...)`) must be evaluated as a function declaration for
`getDefinitionOfFunction()` to be called with.
In the case of imported helpers, the `tslib.__someHelper` expression was
resolved to a function declaration of the form
`export declare function __someHelper(...args: any[][]): any[];`, which
allows `getDefinitionOfFunction()` to correctly map it to a TS helper.
In contrast, in the case of emitted helpers (and regardless of the
module format: `CommonJS`, `ESNext`, `UMD`, etc.)), the `__someHelper`
identifier was resolved to a variable declaration of the form
`var __someHelper = (this && this.__someHelper) || function () { ... }`,
which upon further evaluation was categorized as a `DynamicValue`
(prohibiting further evaluation by the `getDefinitionOfFunction()`).
As a result of the above, emitted TypeScript helpers were not evaluated
in ES5 code.
---
This commit changes the detection of TS helpers to leverage the existing
`KnownFn` feature (previously only used for built-in functions).
`Esm5ReflectionHost` is changed to always return `KnownDeclaration`s for
TS helpers, both imported (`getExportsOfModule()`) as well as emitted
(`getDeclarationOfIdentifier()`).
Similar changes are made to `CommonJsReflectionHost` and
`UmdReflectionHost`.
The `KnownDeclaration`s are then mapped to `KnownFn`s in
`StaticInterpreter`, allowing it to statically evaluate call expressions
involving any kind of TS helpers.
Jira issue: https://angular-team.atlassian.net/browse/FW-1689
PR Close#35191
This is in preparation of using the `KnownFn` type for known TypeScript
helpers (in addition to built-in functions/methods). This will in turn
allow simplifying the detection of both imported and emitted TypeScript
helpers.
PR Close#35191
Prior to this commit, decorator handling logic in Ngtsc used `Error` to throw errors. This commit replaces most of these instances with `FatalDiagnosticError` class, which provider a better diagnostics error (including location of the problematic code).
PR Close#35244
ngcc uses a lockfile to prevent two ngcc instances from executing at the
same time. Previously, if a lockfile was found the current process would
error and exit.
Now, when in async mode, the current process is able to wait for the previous
process to release the lockfile before continuing itself.
PR Close#35131
Pete Bacon Darwin
JoostK
Andrew Scott
Alex Rickabaugh
Alan Agius
crisbeto
Ahn
Andrew Scott
Doug Parker
Charles Lyding
Andrew Kushnir
Olivier Combe
Keen Yee Liau
Paul Gschwendtner
David Neil
Igor Minar
Joey Perrott
Ayaz Hafiz
JiaLiPassion
George Kalpakas
Matias Niemelä
Yiting Wang
Alex Eagle