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
In Ivy's template type checker, event bindings are checked in a closure
to allow for accurate type inference of the `$event` parameter. Because
of the closure, any narrowing effects of template guards will no longer
be in effect when checking the event binding, as TypeScript assumes that
the guard outside of the closure may no longer be true once the closure
is invoked. For more information on TypeScript's Control Flow Analysis,
please refer to https://github.com/microsoft/TypeScript/issues/9998.
In Angular templates, it is known that an event binding can only be
executed when the view it occurs in is currently rendered, hence the
corresponding template guard is known to hold during the invocation of
an event handler closure. As such, it is desirable that any narrowing
effects from template guards are still in effect within the event
handler closure.
This commit tweaks the generated Type-Check Block (TCB) to repeat all
template guards within an event handler closure. This achieves the
narrowing effect of the guards even within the closure.
Fixes#35073
PR Close#35193
This commit implements an experimental integration with tsc_wrapped, where
it can load the Angular compiler as a plugin and perform Angular
transpilation at a user's request.
This is an alternative to the current ngc_wrapped mechanism, which is a fork
of tsc_wrapped from several years ago. tsc_wrapped has improved
significantly since then, and this feature will allow Angular to benefit
from those improvements.
Currently the plugin API between tsc_wrapped and the Angular compiler is a
work in progress, so NgTscPlugin does not yet implement any interfaces from
@bazel/typescript (the home of tsc_wrapped). Instead, an interface is
defined locally to guide this standardization.
PR Close#34792
This commit moves the calculation of `ignoreFiles` - the set of files to be
ignored by a consumer of the `NgCompiler` API - from its `prepareEmit`
operation to its initialization. It's now available as a field on
`NgCompiler`.
This will allow a consumer to skip gathering diagnostics for `ignoreFiles`
as well as skip emit.
PR Close#34792
A bug previously caused the template type-checking diagnostics produced by
TypeScript for template expressions to use -99-prefixed error codes. These
codes are converted to "NG" errors instead of "TS" errors during diagnostic
printing. This commit fixes the issue.
PR Close#35146
In #34021 the ngtsc compiler gained the ability to emit type parameter
constraints, which would generate imports for any type reference that
is used within the constraint. However, the `AbsoluteModuleStrategy`
reference emitter strategy did not consider interface declarations as a
valid declaration it can generate an import for, throwing an error
instead.
This commit fixes the issue by including interface declarations in the
logic that determines whether something is a declaration.
Fixes#34837
PR Close#34849
In #33551, a bug in `ngc --watch` mode was fixed so that a component is
recompiled when its template file is changed. Due to insufficient
normalization of files paths, this fix did not have the desired effect
on Windows.
Fixes#32869
PR Close#34015
Component's decorator handler exposes `preanalyze` method to preload async resources (templates, stylesheets). The logic in preanalysis phase may throw `FatalDiagnosticError` errors that contain useful information regarding the origin of the problem. However these errors from preanalysis phase were not intercepted in TraitCompiler, resulting in just error message text be displayed. This commit updates the logic to handle FatalDiagnosticError and transform it before throwing, so that the result diagnostic errors contain the necessary info.
PR Close#34801
Previously, NgtscProgram lived in the main @angular/compiler-cli package
alongside the legacy View Engine compiler. As a result, the main package
depended on all of the ngtsc internal packages, and a significant portion of
ngtsc logic lived in NgtscProgram.
This commit refactors NgtscProgram and moves the main logic of compilation
into a new 'core' package. The new package defines a new API which enables
implementers of TypeScript compilers (compilers built using the TS API) to
support Angular transpilation as well. It involves a new NgCompiler type
which takes a ts.Program and performs Angular analysis and transformations,
as well as an NgCompilerHost which wraps an input ts.CompilerHost and adds
any extra Angular files.
Together, these two classes are used to implement a new NgtscProgram which
adapts the legacy api.Program interface used by the View Engine compiler
onto operations on the new types. The new NgtscProgram implementation is
significantly smaller and easier to reason about.
The new NgCompilerHost replaces the previous GeneratedShimsHostWrapper which
lived in the 'shims' package.
A new 'resource' package is added to support the HostResourceLoader which
previously lived in the outer compiler package.
As a result of the refactoring, the dependencies of the outer
@angular/compiler-cli package on ngtsc internal packages are significantly
trimmed.
This refactoring was driven by the desire to build a plugin interface to the
compiler so that tsc_wrapped (another consumer of the TS compiler APIs) can
perform Angular transpilation on user request.
PR Close#34887
In #34288, ngtsc was refactored to separate the result of the analysis
and resolve phase for more granular incremental rebuilds. In this model,
any errors in one phase transition the trait into an error state, which
prevents it from being ran through subsequent phases. The ngcc compiler
on the other hand did not adopt this strict error model, which would
cause incomplete metadata—due to errors in earlier phases—to be offered
for compilation that could result in a hard crash.
This commit updates ngcc to take advantage of ngtsc's `TraitCompiler`,
that internally manages all Ivy classes that are part of the
compilation. This effectively replaces ngcc's own `AnalyzedFile` and
`AnalyzedClass` types, together with all of the logic to drive the
`DecoratorHandler`s. All of this is now handled in the `TraitCompiler`,
benefiting from its explicit state transitions of `Trait`s so that the
ngcc crash is a thing of the past.
Fixes#34500
Resolves FW-1788
PR Close#34889
This commit fixes a bug in the incremental rebuild engine of ngtsc, where if
a component was removed from its NgModule, it would not be properly
re-emitted.
The bug stemmed from the fact that whether to emit a file was a decision
based purely on the updated dependency graph, which captures the dependency
structure of the rebuild program. This graph has no edge from the component
to its former module (as it was removed, of course), so the compiler
erroneously decides not to emit the component.
The bug here is that the compiler does know, from the previous dependency
graph, that the component file has logically changed, since its previous
dependency (the module file) has changed. This information was not carried
forward into the set of files which need to be emitted, because it was
assumed that the updated dependency graph was a more accurate source of that
information.
With this commit, the set of files which need emit is pre-populated with the
set of logically changed files, to cover edge cases like this.
Fixes#34813
PR Close#34912
Previously, the template type-checker would always construct a generic
template context type with correct bounds, even when strictTemplates was
disabled. This meant that type-checking of expressions involving that type
was stricter than View Engine.
This commit introduces a 'strictContextGenerics' flag which behaves
similarly to other 'strictTemplates' flags, and switches the inference of
generic type parameters on the component context based on the value of this
flag.
PR Close#34649
FileToModuleHost aliasing supports compilation within environments that have
two properties:
1. A `FileToModuleHost` exists which defines canonical module names for any
given TS file.
2. Dependency restrictions exist which prevent the import of arbitrary files
even if such files are within the .d.ts transitive closure of a
compilation ("strictdeps").
In such an environment, generated imports can only go through import paths
which are already present in the user program. The aliasing system supports
the generation and consumption of such imports at runtime.
`FileToModuleHost` aliasing does not emit re-exports in .d.ts files. This
means that it's safe to rely on alias re-exports in generated .js code (they
are guaranteed to exist at runtime) but not in template type-checking code
(since TS will not be able to follow such imports). Therefore, non-aliased
imports should be used in template type-checking code.
This commit adds a `NoAliasing` flag to `ImportFlags` and sets it when
generating imports in template type-checking code. The testing environment
is also patched to support resolution of FileToModuleHost canonical paths
within the template type-checking program, enabling testing of this change.
PR Close#34649
Previously, `ReferenceEmitter.emit()` took an `ImportMode` enum value, where
one value of the enum allowed forcing new imports to be generated when
emitting a reference to some value or type.
This commit refactors `ImportMode` to be an `ImportFlags` value instead.
Using a bit field of flags will allow future customization of reference
emitting.
PR Close#34649
Previously, when generating template type-checking code, casts to 'any' were
produced as `expr as any`, regardless of the expression. However, for
certain expression types, this led to precedence issues with the cast. For
example, `a !== b` is a `ts.BinaryExpression`, and wrapping it directly in
the cast yields `a !== b as any`, which is semantically equivalent to
`a !== (b as any)`. This is obviously not what is intended.
Instead, this commit adds a list of expression types for which a "bare"
wrapping is permitted. For other expressions, parentheses are added to
ensure correct precedence: `(a !== b) as any`
PR Close#34649
Currently, the template type-checker gives an error if there are multiple
bindings to the same input. This commit aligns the behavior of the template
type-checker with the View Engine runtime: only the first binding to a field
has any effect. The rest are ignored.
PR Close#34649
It's possible to declare multiple inputs for a directive/component which all
map to the same property name. This is usually done in error, as only one of
any bindings to the property will "win".
In the template type-checker, an error was previously being raised as a
result of this ambiguity. Specifically, a type constructor was produced
which required a binding for each field, but only one of the fields had
a value via the binding. TypeScript would (rightfully) error on missing
values for the remaining fields. This ultimately was happening when the
code which generated the default values for "unset" inputs belonging to
directives or pipes used the final mapping from properties to fields as
a source for field names.
Instead, this commit uses the original list of fields to generate unset
input values, which correctly provides values for fields which shared a
property name but didn't receive the final binding.
PR Close#34649
Consider a library that uses a shared constant for host bindings. e.g.
```ts
export const BASE_BINDINGS= {
'[class.mat-themed]': '_isThemed',
}
----
@Directive({
host: {...BASE_BINDINGS, '(click)': '...'}
})
export class Dir1 {}
@Directive({
host: {...BASE_BINDINGS, '(click)': '...'}
})
export class Dir2 {}
```
Previously when these components were shipped as part of the
library to NPM, consumers were able to consume `Dir1` and `Dir2`.
No errors showed up.
Now with Ivy, when ngcc tries to process the library, an error
will be thrown. The error is stating that the host bindings should
be an object (which they obviously are). This happens because
TypeScript transforms the object spread to individual
`Object.assign` calls (for compatibility).
The partial evaluator used by the `@Directive` annotation handler
is unable to process this expression because there is no
integrated support for `Object.assign`. In View Engine, this was
not a problem because the `metadata.json` files from the library
were used to compute the host bindings.
Fixes#34659
PR Close#34661
This commit adds an `exclusive` parameter to the
`FileSystem.writeFile()` method. When this parameter is
true, the method will fail with an `EEXIST` error if the
file already exists on disk.
PR Close#34722
The major one that affects the angular repo is the removal of the bootstrap attribute in nodejs_binary, nodejs_test and jasmine_node_test in favor of using templated_args --node_options=--require=/path/to/script. The side-effect of this is that the bootstrap script does not get the require.resolve patches with explicitly loading the targets _loader.js file.
PR Close#34736
Currently ngtsc looks for the first `ConstructorDeclaration` when figuring out what the parameters are so that it can generate the DI instructions. The problem is that if a constructor has overloads, it'll have several `ConstructorDeclaration` members with a different number of parameters. These changes tweak the logic so it looks for the constructor implementation.
PR Close#34590
Currently the decorator handlers are run against all `SourceFile`s in the compilation, but we shouldn't be doing it against declaration files. This initially came up as a CI issue in #33264 where it was worked around only for the `DirectiveDecoratorHandler`. These changes move the logic into the `TraitCompiler` and `DecorationAnalyzer` so that it applies to all of the handlers.
PR Close#34557
The major one that affects the angular repo is the removal of the bootstrap attribute in nodejs_binary, nodejs_test and jasmine_node_test in favor of using templated_args --node_options=--require=/path/to/script. The side-effect of this is that the bootstrap script does not get the require.resolve patches with explicitly loading the targets _loader.js file.
PR Close#34589
In some cases TypeScript is unable to identify a valid
symbol for an export. In this case it returns an "unknown"
symbol, which does not reference any declarations.
This fix ensures that ngcc does not crash if such a symbol
is encountered by checking whether `symbol.declarations`
exists before accessing it.
The commit does not contain a unit test as it was not possible
to recreate a scenario that had such an "unknown" symbol in
the unit test environment. The fix has been manually checked
against that original issue; and also this check is equivalent to
similar checks elsewhere in the code, e.g.
https://github.com/angular/angular/blob/8d0de89e/packages/compiler-cli/src/ngtsc/reflection/src/typescript.ts#L309Fixes#34560
PR Close#34658
Previously, it was required that both `fullTemplateTypeCheck` and
`strictTemplates` had to be enabled for strict mode to be enabled. This
is strange, as `strictTemplates` implies `fullTemplateTypeCheck`. This
commit makes setting the `fullTemplateTypeCheck` flag optional so that
strict mode can be enabled by just setting `strictTemplates`.
PR Close#34195
It is now an error if '"fullTemplateTypeCheck"' is disabled while
`"strictTemplates"` is enabled, as enabling the latter implies that the
former is also enabled.
PR Close#34195
The compiler has a translation mechanism to convert from an Angular
`Type` to a `ts.TypeNode`, as appropriate. Prior to this change, it
would translate certain Angular expressions into their value equivalent
in TypeScript, instead of the correct type equivalent. This was possible
as the `ExpressionVisitor` interface is not strictly typed, with `any`s
being used for return values.
For example, a literal object was translated into a
`ts.ObjectLiteralExpression`, containing `ts.PropertyAssignment` nodes
as its entries. This has worked without issues as their printed
representation is identical, however it was incorrect from a semantic
point of view. Instead, a `ts.TypeLiteralNode` is created with
`ts.PropertySignature` as its members, which corresponds with the type
declaration of an object literal.
PR Close#34021
In Ivy's template type checker, type constructors are created for all
directive types to allow for accurate type inference to work. The type
checker has two strategies for dealing with such type constructors:
1. They can be emitted local to the type check block/type check file.
2. They can be emitted as static `ngTypeCtor` field into the directive
itself.
The first strategy is preferred, as it avoids having to update the
directive type which would cause a more expensive rebuild. However, this
strategy is not suitable for directives that have constrained generic
types, as those constraints would need to be present on the local type
constructor declaration. This is not trivial, as it requires that any
type references within a type parameter's constraint are imported into
the local context of the type check block.
For example, lets consider the `NgForOf` directive from '@angular/core'
looks as follows:
```typescript
import {NgIterable} from '@angular/core';
export class NgForOf<T, U extends NgIterable<T>> {}
```
The type constructor will then have the signature:
`(o: Pick<i1.NgForOf<T, U>, 'ngForOf'>) => i1.NgForOf<T, U>`
Notice how this refers to the type parameters `T` and `U`, so the type
constructor needs to be emitted into a scope where those types are
available, _and_ have the correct constraints.
Previously, the template type checker would detect the situation where a
type parameter is constrained, and would emit the type constructor
using strategy 2; within the directive type itself. This approach makes
any type references within the generic type constraints lexically
available:
```typescript
export class NgForOf<T, U extends NgIterable<T>> {
static ngTypeCtor<T = any, U extends NgIterable<T> = any>
(o: Pick<NgForOf<T, U>, 'ngForOf'>): NgForOf<T, U> { return null!; }
}
```
This commit introduces the ability to emit a type parameter with
constraints into a different context, under the condition that it can
be imported from an absolute module. This allows a generic type
constructor to be emitted into a type check block or type check file
according to strategy 1, as imports have been generated for all type
references within generic type constraints. For example:
```typescript
import * as i0 from '@angular/core';
import * as i1 from '@angular/common';
const _ctor1: <T = any, U extends i0.NgIterable<T> = any>
(o: Pick<i1.NgForOf<T, U>, 'ngForOf'>) => i1.NgForOf<T, U> = null!;
```
Notice how the generic type constraint of `U` has resulted in an import
of `@angular/core`, and the `NgIterable` is transformed into a qualified
name during the emitting process.
Resolves FW-1739
PR Close#34021
Angular View Engine uses global knowledge to compile the following code:
```typescript
export class Base {
constructor(private vcr: ViewContainerRef) {}
}
@Directive({...})
export class Dir extends Base {
// constructor inherited from base
}
```
Here, `Dir` extends `Base` and inherits its constructor. To create a `Dir`
the arguments to this inherited constructor must be obtained via dependency
injection. View Engine is able to generate a correct factory for `Dir` to do
this because via metadata it knows the arguments of `Base`'s constructor,
even if `Base` is declared in a different library.
In Ivy, DI is entirely a runtime concept. Currently `Dir` is compiled with
an ngDirectiveDef field that delegates its factory to `getInheritedFactory`.
This looks for some kind of factory function on `Base`, which comes up
empty. This case looks identical to an inheritance chain with no
constructors, which works today in Ivy.
Both of these cases will now become an error in this commit. If a decorated
class inherits from an undecorated base class, a diagnostic is produced
informing the user of the need to either explicitly declare a constructor or
to decorate the base class.
PR Close#34460
Adds a compilation error if the consumer tries to pass in an undecorated class into the `providers` of an `NgModule`, or the `providers`/`viewProviders` arrays of a `Directive`/`Component`.
PR Close#34460
The function `makeTemplateDiagnostic` was accepting an error code of type
`number`, making it easy to accidentally pass an `ErrorCode` directly and
not convert it to an Angular diagnostic code first.
This commit refactors `makeTemplateDiagnostic` to accept `ErrorCode` up
front, and convert it internally. This is less error-prone.
PR Close#34460
Previously, ngtsc would perform scope analysis (which directives/pipes are
available inside a component's template) and template type-checking of that
template as separate steps. If a component's scope was somehow invalid (e.g.
its NgModule imported something which wasn't another NgModule), the
component was treated as not having a scope. This meant that during template
type-checking, errors would be produced for any invalid expressions/usage of
other components that should have been in the scope.
This commit changes ngtsc to skip template type-checking of a component if
its scope is erroneous (as opposed to not present in the first place). Thus,
users aren't overwhelmed with diagnostic errors for the template and are
only informed of the root cause of the problem: an invalid NgModule scope.
Fixes#33849
PR Close#34460
Previously each NgModule trait checked its own scope for valid declarations
during 'resolve'. This worked, but caused the LocalModuleScopeRegistry to
declare that NgModule scopes were valid even if they contained invalid
declarations.
This commit moves the generation of diagnostic errors to the
LocalModuleScopeRegistry where it belongs. Now the registry can consider an
NgModule's scope to be invalid if it contains invalid declarations.
PR Close#34460
The template type checker generates TypeScript expressions for any
expression that occurs in a template, so that TypeScript can check it
and produce errors. Some expressions as they occur in a template may be
translated into TypeScript code multiple times, for instance a binding
to a directive input that has a template guard.
One example would be the `NgIf` directive, which has a template guard to
narrow the type in the template as appropriate. Given the following
template:
```typescript
@Component({
template: '<div *ngIf="person">{{ person.name }}</div>'
})
class AppComponent {
person?: { name: string };
}
```
A type check block (TCB) with roughly the following structure is
created:
```typescript
function tcb(ctx: AppComponent) {
const t1 = NgIf.ngTypeCtor({ ngIf: ctx.person });
if (ctx.person) {
"" + ctx.person.name;
}
}
```
Notice how the `*ngIf="person"` binding is present twice: once in the
type constructor call and once in the `if` guard. As such, TypeScript
will check both instances and would produce duplicate errors, if any
were found.
Another instance is when the safe navigation operator is used, where an
expression such as `person?.name` is emitted into the TCB as
`person != null ? person!.name : undefined`. As can be seen, the
left-hand side expression `person` occurs twice in the TCB.
This commit adds the ability to insert markers into the TCB that
indicate that any errors within the expression should be ignored. This
is similar to `@ts-ignore`, however it can be applied more granularly.
PR Close#34417
George Kalpakas
Andrew Kushnir
Pete Bacon Darwin
JoostK
Alex Rickabaugh
Alan Agius
Igor Minar
Paul Gschwendtner
Greg Magolan
Andrius
crisbeto
atscott