The decorator downleveling transform patches `ts.EmitResolver.isReferencedAliasDeclaration`
to prevent elision of value imports that occur only in a type-position, which would
inadvertently install the patch repeatedly for each source file in the program.
This could potentially result in a stack overflow when a very large number of files is
present in the program.
This commit fixes the issue by ensuring that the patch is only applied once.
This is also a slight performance improvement, as `isReferencedAliasDeclaration`
is no longer repeatedly calling into all prior installed patch functions.
Fixes#40276
PR Close#40374
There is a compiler transform that downlevels Angular class decorators
to static properties so that metadata is available for JIT compilation.
The transform was supposed to ignore non-Angular decorators but it was
actually completely dropping decorators that did not conform to a very
specific syntactic shape (i.e. the decorator was a simple identifier, or
a namespaced identifier).
This commit ensures that all non-Angular decorators are kepts as-is
even if they are built using a syntax that the Angular compiler does not
understand.
Fixes#39574
PR Close#39577
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
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
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
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
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
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
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 compiler exports a `formatDiagnostics` function which consumers can use
to print both ts and ng diagnostics. However, this function was previously
using the "old" style TypeScript diagnostics, as opposed to the modern
diagnostic printer which uses terminal colors and prints additional context
information.
This commit updates `formatDiagnostics` to use the modern formatter, plus to
update Ivy's negative error codes to Angular 'NG' errors.
The Angular CLI needs a little more work to use this function for printing
TS diagnostics, but this commit alone should fix Bazel builds as ngc-wrapped
goes through `formatDiagnostics`.
PR Close#34234
During the creation of an Angular program in the compiler, a check is
done to verify whether the version of TypeScript is considered
supported, producing an error if it is not. This check was missing in
the Ivy compiler, so users may have ended up running an unsupported
TypeScript version inadvertently.
Resolves FW-1643
PR Close#33377
Injector defs are not considered public API, so the property
that contains them should be prefixed with Angular's marker
for "private" ('ɵ') to discourage apps from relying on def
APIs directly.
This commit adds the prefix and shortens the name from
ngInjectorDef to inj. This is because property names
cannot be minified by Uglify without turning on property
mangling (which most apps have turned off) and are thus
size-sensitive.
PR Close#33151
Fixes all TypeScript failures caused by enabling the `--strict`
flag for test source files. We also want to enable the strict
options for tests as the strictness enforcement improves the
overall codehealth, unveiled common issues and additionally it
allows us to enable `strict` in the `tsconfig.json` that is picked
up by IDE's.
PR Close#30993
To improve cross platform support, all file access (and path manipulation)
is now done through a well known interface (`FileSystem`).
For testing a number of `MockFileSystem` implementations are provided.
These provide an in-memory file-system which emulates operating systems
like OS/X, Unix and Windows.
The current file system is always available via the static method,
`FileSystem.getFileSystem()`. This is also used by a number of static
methods on `AbsoluteFsPath` and `PathSegment`, to avoid having to pass
`FileSystem` objects around all the time. The result of this is that one
must be careful to ensure that the file-system has been initialized before
using any of these static methods. To prevent this happening accidentally
the current file system always starts out as an instance of `InvalidFileSystem`,
which will throw an error if any of its methods are called.
You can set the current file-system by calling `FileSystem.setFileSystem()`.
During testing you can call the helper function `initMockFileSystem(os)`
which takes a string name of the OS to emulate, and will also monkey-patch
aspects of the TypeScript library to ensure that TS is also using the
current file-system.
Finally there is the `NgtscCompilerHost` to be used for any TypeScript
compilation, which uses a given file-system.
All tests that interact with the file-system should be tested against each
of the mock file-systems. A series of helpers have been provided to support
such tests:
* `runInEachFileSystem()` - wrap your tests in this helper to run all the
wrapped tests in each of the mock file-systems.
* `addTestFilesToFileSystem()` - use this to add files and their contents
to the mock file system for testing.
* `loadTestFilesFromDisk()` - use this to load a mirror image of files on
disk into the in-memory mock file-system.
* `loadFakeCore()` - use this to load a fake version of `@angular/core`
into the mock file-system.
All ngcc and ngtsc source and tests now use this virtual file-system setup.
PR Close#30921
Note that this fixes `compiler-cli` tests within `compiler-cli/test`,
but there seem to be remaining `ngcc` tests within `compiler-cli/src`
which aren't working on Windows. This is out-of-scope for this commit.
PR Close#28352
Users might have run the CSS Preprocessor tool *before* the Angular
compiler. For example, we do it that way under Bazel. This means that
the design-time reference is different from the compile-time one - the
input to the Angular compiler is a plain .css file.
We assume that the preprocessor does a trivial 1:1 mapping using the same
basename with a different extension.
PR Close#28166
These tests are not relevant to Ivy:
//packages/compiler-cli/test/diagnostics:check_types
//packages/compiler-cli/test/diagnostics:expression_diagnostics
//packages/compiler-cli/test/transformers:test
//packages/compiler-cli/test:extract_i18n
The //packages/compiler-cli/test:ngtools_api test has 2 specs, one of
which passes and the other of which depends on ngtsc supporting lazy
routes. It's now disabled with fixmeIvy().
PR Close#27301
In a more specific scenario: Considering people use a custom TypeScript compiler host with `NGC`, they _could_ expect only posix paths in methods like `writeFile`. This at first glance sounds like a trivial issue that should be just fixed by the actual compiler host, but usually TypeScript internal API's just pass around posix normalized paths, and therefore it would be good to follow the same standards when passing JSON genfiles to the `CompilerHost`.
For normal TypeScript files (and TS genfiles), this is already consistent because those will be handled by the actual TypeScript `Program` (see `emitCallback`).
PR Close#27062
We are close enough to blacklist a few test targets, rather than whitelist targets to run...
Because bazel rules can be composed of other rules that don't inherit tags automatically,
I had to explicitly mark all of our ts_library and ng_module targes with "ivy-local" and
"ivy-jit" tags so that we can create a query that excludes all fixme- tagged targets even
if those targets are composed of other targets that don't inherit this tag.
This is the updated overview of ivy related bazel tags:
- ivy-only: target that builds or runs only under ivy
- fixme-ivy-jit: target that doesn't yet build or run under ivy with --compile=jit
- fixme-ivy-local: target that doesn't yet build or run under ivy with --compile=local
- no-ivy-jit: target that is not intended to build or run under ivy with --compile=jit
- no-ivy-local: target that is not intended to build or run under ivy with --compile=local
PR Close#26471
Closure requires @nocollapse on Ivy definition static fields in order
to not convert them to standalone constants. However tsickle, the tool
which would ordinarily be responsible for adding @nocollapse, doesn't
properly annotate fields which are added synthetically via transforms.
So this commit adds @nocollapse by applying regular expressions against
code during the final write to disk.
PR Close#25775
In tsc 3.0 the check that enables program structure reuse in tryReuseStructureFromOldProgram has changed
and now uses identity comparison on arrays within CompilerOptions. Since we recreate the options
on each incremental compilation, we now fail this check.
After this change the default set of options is reused in between incremental compilations, but we still
allow options to be overriden if needed.
PR Close#25275
With these changes, the types are a little stricter now and also not
compatible with Protractor's jasmine-like syntax. So, we have to also
use `@types/jasminewd2` for e2e tests (but not for non-e2e tests).
I also had to "augment" `@types/jasminewd2`, because the latest
typings from [DefinitelyTyped][1] do not reflect the fact that the
`jasminewd2` version (v2.1.0) currently used by Protractor supports
passing a `done` callback to a spec.
[1]: 566e039485/types/jasminewd2/index.d.ts (L9-L15)Fixes#23952Closes#24733
PR Close#19904
Joey Perrott
JoostK
Charles Lyding
Pete Bacon Darwin
Alan Agius
crisbeto
Paul Gschwendtner
Alex Rickabaugh
Greg Magolan
atscott
Kara Erickson
Alex Eagle
Misko Hevery
Igor Minar
Alex Eagle
George Kalpakas
Mark Levy
Oussama Ben Brahim
Chuck Jazdzewski
Veres Lajos