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 propagates the `sourceSpan` and `valueSpan` of a `VariableBinding`
in a microsyntax expression to `ParsedVariable`, and subsequently to
View Engine Variable AST and Ivy Variable AST.
Note that this commit does not propagate the `keySpan`, because it involves
significant changes to the template AST.
PR Close#36047
Prior to this commit, Ivy compiler didn't handle directive inputs with interpolations located on `<ng-template>` elements (e.g. `<ng-template dir="{{ field }}">`). That was the case for regular inputs as well as inputs that should be processed via i18n subsystem (e.g. `<ng-template i18n-dir dir="Hello {{ name }}">`). This commit adds support for such expressions for explicit `<ng-template>`s as well as a number of tests to confirm the behavior.
Fixes#35752.
PR Close#35984
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
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
`ɵɵNgOnChangesFeature()` would set `ngInherit`, which is a side effect and also not necessary. This was pulled out to module scope so the function itself can be pure. Since it only curries another function, the call is entirely unnecessary. Updated the compiler to only generate a reference to this function, rather than a call to it, and removed the extra curry indirection.
PR Close#35769
Prior to this commit, i18n attributes defined on `<ng-template>` tags were not processed by the compiler. This commit adds the necessary logic to handle i18n attributes in the same way how these attrs are processed for regular elements.
PR Close#35681
When the `NgIf` directive is used in a template, its context variables
can be used to capture the bound value. This is typically used together
with a pipe or function call, where the resulting value is captured in a
context variable. There's two syntax forms available:
1. Binding to `NgIfContext.ngIf` using the `as` syntax:
```html
<span *ngIf="(user$ | async) as user">{{user.name}}</span>
```
2. Binding to `NgIfContext.$implicit` using the `let` syntax:
```html
<span *ngIf="user$ | async; let user">{{user.name}}</span>
```
Because of the semantics of `ngIf`, it is known that the captured
context variable is non-nullable, however the template type checker
would not consider them as such and still report errors when
`strictNullTypes` is enabled.
This commit updates `NgIf`'s context guard to make the types of the
context variables non-nullable, avoiding the issue.
Fixes#34572
PR Close#35125
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
In #33705 we made it so that we generate pure functions for object/array literals in order to avoid having them be shared across elements/views. The problem this introduced is that further down the line the `ContantPool` uses the generated literal in order to figure out whether to share an existing factory or to create a new one. `ConstantPool` determines whether to share a factory by creating a key from the AST node and using it to look it up in the factory cache, however the key generation function didn't handle function invocations and replaced them with `null`. This means that the key for `{foo: pureFunction0(...)}` and `{foo: null}` are the same.
These changes rework the logic so that instead of generating a `null` key
for function invocations, we generate a variable called `<unknown>` which
shouldn't be able to collide with anything.
Fixes#35298.
PR Close#35481
Currently Ivy always generates the `$event` function argument, even if it isn't being used by the listener expressions. This can lead to unnecessary bytes being generated, because optimizers won't remove unused arguments by default. These changes add some logic to avoid adding the argument when it isn't required.
PR Close#35097
Prior to this commit, decorator handling logic in Ngtsc used `Error` to throw errors. This commit replaces most of these instances with `FatalDiagnosticError` class, which provider a better diagnostics error (including location of the problematic code).
PR Close#35244
In Ivy's template type checker, event bindings are checked in a closure
to allow for accurate type inference of the `$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
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 #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
We had some logic for generating and passing in the `elIndex` parameter into the `hostBindings` function, but it wasn't actually being used for anything. The only place left that had a reference to it was the `StylingBuilder` and it only stored it without referencing it again.
PR Close#34969
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
NOTE: This change must be reverted with previous deletes so that it code remains in build-able state.
This change deletes old styling code and replaces it with a simplified styling algorithm.
The mental model for the new algorithm is:
- Create a linked list of styling bindings in the order of priority. All styling bindings ere executed in compiled order and than a linked list of bindings is created in priority order.
- Flush the style bindings at the end of `advance()` instruction. This implies that there are two flush events. One at the end of template `advance` instruction in the template. Second one at the end of `hostBindings` `advance` instruction when processing host bindings (if any).
- Each binding instructions effectively updates the string to represent the string at that location. Because most of the bindings are additive, this is a cheap strategy in most cases. In rare cases the strategy requires removing tokens from the styling up to this point. (We expect that to be rare case)S Because, the bindings are presorted in the order of priority, it is safe to resume the processing of the concatenated string from the last change binding.
PR Close#34616
Compiler keeps track of number of slots (`vars`) which are needed for binding instructions. Normally each binding instructions allocates a single slot in the `LView` but styling instructions need to allocate two slots.
PR Close#34616
This change moves information from instructions to declarative position:
- `ɵɵallocHostVars(vars)` => `DirectiveDef.hostVars`
- `ɵɵelementHostAttrs(attrs)` => `DirectiveDef.hostAttrs`
When merging directives it is necessary to know about `hostVars` and `hostAttrs`. Before this change the information was stored in the `hostBindings` function. This was problematic, because in order to get to the information the `hostBindings` would have to be executed. In order for `hostBindings` to be executed the directives would have to be instantiated. This means that the directive instantiation would happen before we had knowledge about the `hostAttrs` and as a result the directive could observe in the constructor that not all of the `hostAttrs` have been applied. This further complicates the runtime as we have to apply `hostAttrs` in parts over many invocations.
`ɵɵallocHostVars` was unnecessarily complicated because it would have to update the `LView` (and Blueprint) while existing directives are already executing. By moving it out of `hostBindings` function we can access it statically and we can create correct `LView` (and Blueprint) in a single pass.
This change only changes how the instructions are generated, but does not change the runtime much. (We cheat by emulating the old behavior by calling `ɵɵallocHostVars` and `ɵɵelementHostAttrs`) Subsequent change will refactor the runtime to take advantage of the static information.
PR Close#34683
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
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
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
This patch removes the need for the styleSanitizer() instruction in
favor of passing the sanitizer into directly into the styleProp
instruction.
This patch also increases the binding index size for all style/class bindings in preparation for #34418
PR Close#34480
Pipes in host binding expressions are not supported in View Engine and Ivy, but in some more complex cases (like `(value | pipe) === true`) compiler was not reporting errors. This commit extends Ivy logic to detect pipes in host binding expressions and throw in cases bindings are present. View Engine behavior remains the same.
PR Close#34655
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
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
The `getProjectAsAttrValue` in `node_selector_matcher` finds the
ProjectAs marker and then additionally checks that the marker appears in
an even index of the node attributes because "attribute names are stored
at even indexes". This is true for "regular" attribute bindings but
classes, styles, bindings, templates, and i18n do not necessarily follow
this rule because there can be an uneven number of them, causing the
next "special" attribute "name" to appear at an odd index. To address
this issue, ensure ngProjectAs is placed right after "regular"
attributes.
PR Close#34617
Prior to this commit, there were no `advance` instructions generated before `i18nExp` instructions and as a result, lifecycle hooks for components used inside i18n blocks were flushed too late. This commit adds the logic to generate `advance` instructions in front of `i18nExp` ones (similar to what we have in other places like interpolations, property bindings, etc), so that the necessary lifecycle hooks are flushed before expression value is captured.
PR Close#34436
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
Ayaz Hafiz
JoostK
Alex Rickabaugh
Keen Yee Liau
Andrew Kushnir
Matias Niemelä
Doug Parker
crisbeto
Miško Hevery
Greg Magolan
atscott
Andrew Scott