1264 Commits

Author SHA1 Message Date
Doug Parker
7f8c2225f2 fix(compiler): mark NgModuleFactory construction as not side effectful (#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. 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
2020-07-29 13:32:08 -07:00
Doug Parker
887c350f9d refactor(compiler): wrap large strings in function (#38253)
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
2020-07-29 13:31:03 -07:00
Alex Rickabaugh
d8c07b83c3 refactor(compiler-cli): support type-checking a single component (#38105)
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
2020-07-29 10:31:21 -07:00
Alex Rickabaugh
8f73169979 refactor(compiler-cli): add TemplateId to template diagnostics (#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
2020-07-29 10:31:20 -07:00
Alex Rickabaugh
3c0424e7e0 refactor(compiler-cli): allow overriding templates in the type checker (#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
2020-07-29 10:31:20 -07:00
Alex Rickabaugh
de14b2c670 refactor(compiler-cli): efficient single-file type checking diagnostics (#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
2020-07-29 10:31:20 -07:00
Alex Rickabaugh
c573d91285 refactor(compiler-cli): allow program strategies to opt out of inlining (#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
2020-07-29 10:31:20 -07:00
Alex Rickabaugh
16c7441c2f refactor(compiler-cli): introduce the TemplateTypeChecker abstraction (#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
2020-07-29 10:31:20 -07:00
Alex Rickabaugh
736f6337b2 refactor(compiler-cli): make file/shim split 1:n instead of 1:1 (#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
2020-07-29 10:31:20 -07:00
Andrew Scott
65cc0c8bd6 fix(compiler-cli): Add support for string literal class members (#38226)
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
2020-07-27 15:26:27 -07:00
Andrew Kushnir
8e5969bb52 fix(compiler): share identical stylesheets between components in the same file (#38213)
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
2020-07-27 10:04:30 -07:00
Andrew Kushnir
2fdc18b42c refactor(compiler): separate compilation and transform phases (#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
2020-07-27 10:04:30 -07:00
Pete Bacon Darwin
b358495a6c fix(ngcc): report a warning if ngcc tries to use a solution-style tsconfig (#38003)
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
2020-07-14 13:21:31 -07:00
Pete Bacon Darwin
6b311552f0 fix(compiler-cli): ensure file_system handles mixed Windows drives (#37959)
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
2020-07-13 12:05:21 -07:00
Olivier Combe
6eb868b63a build(compiler-cli): fix bazel deps rules for ngtsc testing packages (#37977)
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
2020-07-08 12:05:22 -07:00
Alex Rickabaugh
71956250dd perf(compiler-cli): fix memory leak in retained incremental state (#37835)
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
2020-06-29 16:34:51 -07:00
Keen Yee Liau
e0eeb4afcb refactor(compiler-cli): Remove any cast for CompilerHost (#37079)
This commit removes the FIXME for casting CompilerHost to any since
google3 is now already on TS 3.8.

PR Close #37079
2020-06-26 11:08:17 -07:00
Alex Rickabaugh
2cbc429291 test(compiler-cli): disable DynamicValue diagnostic tests on Windows (#37763)
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
2020-06-25 17:04:57 -07:00
Alex Rickabaugh
8572e885b4 test(compiler-cli): fix assertion of diagnostic filename on Windows (#37758)
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
2020-06-25 15:40:43 -07:00
JoostK
ce879fc416 refactor(compiler-cli): more accurate reporting of complex function call (#37587)
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
2020-06-25 14:16:35 -07:00
JoostK
712f1bd0b7 feat(compiler-cli): explain why an expression cannot be used in AOT compilations (#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
2020-06-25 14:16:35 -07:00
JoostK
d2fb552116 refactor(compiler-cli): create diagnostics using ts.DiagnosticRelatedInformation (#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
2020-06-25 14:16:35 -07:00
Alex Rickabaugh
5103d908c8 perf(compiler-cli): fix regressions in incremental program reuse (#37641)
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
2020-06-25 14:12:20 -07:00
Pete Bacon Darwin
07a07e34bc fix(compiler-cli): only read source-map comment from last line (#32912)
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
2020-06-25 14:10:03 -07:00
Pete Bacon Darwin
dda3f49952 refactor(compiler): add source-map spans to localized strings (#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
2020-06-25 14:10:03 -07:00
Pete Bacon Darwin
decd95e7f0 fix(compiler-cli): ensure source-maps can handle webpack:// protocol (#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
2020-06-25 14:10:03 -07:00
Pete Bacon Darwin
6abb8d0d91 feat(compiler-cli): add SourceFile.getOriginalLocation() to sourcemaps package (#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
2020-06-25 14:10:03 -07:00
Pete Bacon Darwin
5c40fd65fa refactor(compiler-cli): tidy up file_system BUILD.bazel file_system (#37114)
* Re-order the `load` and `package` statements
* Make `srcs` glob more generic
* Remove unnecessary dependencies

PR Close #37114
2020-06-22 13:38:47 -07:00
Pete Bacon Darwin
2b53b07c70 refactor(ngcc): move sourcemaps into ngtsc (#37114)
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
2020-06-22 13:38:47 -07:00
Pete Bacon Darwin
6de5a12a9d refactor(ngcc): move logging code into ngtsc (#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
2020-06-22 13:38:47 -07:00
Paul Gschwendtner
66e6b932d8 refactor(compiler-cli): skip class decorators in tooling constructor parameters transform (#37545)
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: 401ef71ae5b01be95d124184a0b6936fc453a5d4 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
2020-06-15 12:47:57 -07:00
Alex Rickabaugh
300c2fec9c refactor(compiler-cli): make IncrementalBuild strategy configurable (#37339)
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
2020-06-15 09:50:08 -07:00
crisbeto
2e355fd4d3 fix(compiler): unable to resolve destructuring variable declarations (#37497)
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
2020-06-11 19:10:04 -07:00
David Neil
8c682c52b1 fix(ngcc): use annotateForClosureCompiler option (#36652)
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
2020-06-11 11:12:56 -07:00
Paul Gschwendtner
401ef71ae5 fix(compiler-cli): downlevel angular decorators to static properties (#37382)
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
2020-06-10 09:24:11 -07:00
Igor Minar
aaa20093b2 ci: special case tooling-cli-shared-api review group (#37467)
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
2020-06-05 19:23:52 -07:00
Andrew Scott
65c3888d01 docs: update file header to be correct (#37425)
The file header should be Google LLC rather than Google Inc. because it is now an LLC after Alphabet Holdings was formed.

PR Close #37425
2020-06-03 15:31:29 -07:00
Alex Rickabaugh
e648a0c4ca refactor(compiler-cli): extract NgCompilerAdapter interface (#37118)
`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
2020-06-03 13:29:44 -07:00
Alex Rickabaugh
965a688c97 fix(compiler-cli): use ModuleWithProviders type if static eval fails (#37126)
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
2020-06-03 13:23:16 -07:00
Joey Perrott
d1ea1f4c7f build: update license headers to reference Google LLC (#37205)
Update the license headers throughout the repository to reference Google LLC
rather than Google Inc, for the required license headers.

PR Close #37205
2020-05-26 14:26:58 -04:00
Pete Bacon Darwin
d42a912343 refactor(compiler-cli): expose the walkForDeclaration() function (#37206)
This test helper can be useful when searching for nodes within an IIFE.
Exporting it here is helpful in ngcc reflection tests.

PR Close #37206
2020-05-20 13:30:31 -07:00
Pete Bacon Darwin
3dfc7703c2 fix(compiler-cli): ensure LogicalFileSystem maintains case in paths (#37008)
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
2020-05-18 10:28:18 -07:00
Alan Agius
6466fb20c2 refactor: remove support for TypeScript 3.8 (#37129)
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
2020-05-18 09:13:37 -07:00
Pete Bacon Darwin
4e1b5e43fa fix(compiler-cli): compute the correct target output for $localize messages (#36989)
In some versions of TypeScript, the transformation of synthetic
`$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
2020-05-14 10:50:30 -07:00
Pete Bacon Darwin
dbcaf22805 refactor(compiler-cli): delegate hasBaseClass() to getBaseClassExpression() (#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
2020-05-14 10:50:28 -07:00
Pete Bacon Darwin
0066a1ae70 refactor(compiler-cli): simplify and clarify TypeScriptReflectionHost.isClass() (#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
2020-05-14 10:50:28 -07:00
Alan Agius
13ba84731f build: prepare for TypeScript 3.9 (#36989)
- Fix several compilation errors
- Update @microsoft/api-extractor to be compatible with TypeScript 3.9

PR Close #36989
2020-05-14 10:50:28 -07:00
Pete Bacon Darwin
5d12c19ce9 refactor(compiler-cli): support Buffer files in FileSystem (#36843)
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
2020-05-13 15:52:48 -07:00
Ayaz Hafiz
eb34aa551a feat(compiler): add name spans for property reads and method calls (#36826)
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
2020-05-08 14:42:42 -07:00
Alex Rickabaugh
42d1091d6a fix(compiler-cli): don't try to tag non-ts files as shims (#36987)
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
2020-05-07 14:45:05 -07:00