The partial declaration of a component includes the list of directives
that are used in its template, including some metadata of the directive
which can be used during actual compilation of the component. Used
components are currently part of this list, as components are also
directives. This commit splits the used components into a dedicate
property in the partial declaration, which allows for template
compilation to optimize the generated code for components.
PR Close#41104
This commit complements the support for the `__spreadArray` helper that
was added in microsoft/TypeScript#41523. The prior helpers `__spread`
and `__spreadArrays` used the `__read` helper internally, but the helper
is now emitted as an argument to `__spreadArray` so ngcc now needs to
support evaluating it statically. The real implementation of `__read`
reads an iterable into an array, but for ngcc's static evaluation
support it is sufficient to only deal with arrays as is. Additionally,
the optional `n` parameter is not supported as that is only emitted for
array destructuring syntax, which ngcc does not have to support.
PR Close#41201
In TypeScript 4.2 the `__spread` and `__spreadArrays` helpers were both
replaced by the new helper function `__spreadArray` in
microsoft/TypeScript#41523. These helpers may be used in downleveled
JavaScript bundles that ngcc has to process, so ngcc has the ability to
statically detect these helpers and provide evaluation logic for them.
Because Angular is adopting support for TypeScript 4.2 it becomes
possible for libraries to be compiled by TypeScript 4.2 and thus ngcc
has to add support for the `__spreadArray` helper. The deprecated
`__spread` and `__spreadArrays` helpers are not affected by this change.
Closes#40394
PR Close#41201
The recently introduced typings-only mode in ngcc would incorrectly
write compiled JavaScript files if typings-only mode was requested, in
case the typings of the entry-point had already been processed in a
prior run of ngcc. The corresponding format property for which the
JavaScript files were written were not marked as processed, though, as
the typings-only mode excluded the format property itself from being
marked as processed. Consequently, subsequent runs of ngcc would not
consider the entry-point to have been processed and recompile the
JavaScript bundle once more, resulting in duplicate ngcc imports.
Fixes#41198
PR Close#41209
This commit changes the partial compilation so that it outputs declaration
calls rather than definition calls for NgModules and Injectors.
The JIT compiler and the linker are updated to be able to handle these
new declarations.
PR Close#41080
There were a number of almost identical interfaces used in
the same way throughout the Render3 compiler code.
This commit changes the compiler to use the same interface
throughout.
PR Close#41080
This function is declared in multiple places. The instances inside
`compiler` are slightly different to those in `compiler-cli`. So this
commit consolidates them into two reusable functions.
PR Close#41080
BREAKING CHANGE:
Switching default of `emitDistinctChangesOnlyDefaultValue`
which changes the default behavior and may cause some applications which
rely on the incorrect behavior to fail.
`emitDistinctChangesOnly` flag has also been deprecated and will be
removed in a future major release.
The previous implementation would fire changes `QueryList.changes.subscribe`
whenever the `QueryList` was recomputed. This resulted in an artificially
high number of change notifications, as it is possible that recomputing
`QueryList` results in the same list. When the `QueryList` gets recomputed
is an implementation detail, and it should not be the thing that determines
how often change event should fire.
Unfortunately, fixing the behavior outright caused too many existing
applications to fail. For this reason, Angular considers this fix a
breaking fix and has introduced a flag in `@ContentChildren` and
`@ViewChildren`, that controls the behavior.
```
export class QueryCompWithStrictChangeEmitParent {
@ContentChildren('foo', {
// This option is the new default with this change.
emitDistinctChangesOnly: true,
})
foos!: QueryList<any>;
}
```
For backward compatibility before v12
`emitDistinctChangesOnlyDefaultValue` was set to `false. This change
changes the default to `true`.
PR Close#41121
The Angular compiler creates two `ts.Program`s; one for emit and one for
template type-checking. The creation of the type-check program could
benefit from reusing the `ts.ModuleResolutionCache` that was primed
during the creation of the emit program. This requires that the compiler
host implements `resolveModuleNames`, as otherwise TypeScript will setup
a `ts.ModuleResolutionHost` of its own for both programs.
This commit ensures that `resolveModuleNames` is always implemented,
even if the originally provided compiler host does not. This is
beneficial for the `ngc` binary.
PR Close#39693
Previously, injector definitions contained a `factory` property that
was used to create a new instance of the associated NgModule class.
Now this factory has been moved to its own `ɵfac` static property on the
NgModule class itself. This is inline with how directives, components and
pipes are created.
There is a small size increase to bundle sizes for each NgModule class,
because the `ɵfac` takes up a bit more space:
Before:
```js
let a = (() => {
class n {}
return n.\u0275mod = c.Cb({type: n}),
n.\u0275inj = c.Bb({factory: function(t) { return new (t || n) }, imports: [[e.a.forChild(s)], e.a]}),
n
})(),
```
After:
```js
let a = (() => {
class n {}
return n.\u0275fac = function(t) { return new (t || n) },
n.\u0275mod = c.Cb({type: n}),
n.\u0275inj = c.Bb({imports: [[r.a.forChild(s)], r.a]}),
n
})(),
```
In other words `n.\u0275fac = ` is longer than `factory: ` (by 5 characters)
and only because the tooling insists on encoding `ɵ` as `\u0275`.
This can be mitigated in a future PR by only generating the `ɵfac` property
if it is actually needed.
PR Close#41022
This commit adds a semi-comprehensive README file which describes the
design goals and implementation of the template type checking engine,
which powers the Angular Language Service as well as the main compiler's
understanding of types in templates.
PR Close#41004
The compiler performs cycle analysis for the used directives and pipes
of a component's template to avoid introducing a cyclic import into the
generated output. The used directives and pipes are represented by their
output expression which would typically be an `ExternalExpr`; those are
responsible for the generation of an `import` statement. Cycle analysis
needs to determine the `ts.SourceFile` that would end up being imported
by these `ExternalExpr`s, as the `ts.SourceFile` is then checked against
the program's `ImportGraph` to determine if the import is allowed, i.e.
does not introduce a cycle. To accomplish this, the `ExternalExpr` was
dissected and ran through module resolution to obtain the imported
`ts.SourceFile`.
This module resolution step is relatively expensive, as it typically
needs to hit the filesystem. Even in the presence of a module resolution
cache would these module resolution requests generally see cache misses,
as the generated import originates from a file for which the cache has
not previously seen the imported module specifier.
This commit removes the need for the module resolution by wrapping the
generated `Expression` in an `EmittedReference` struct. This allows the
reference emitter mechanism that is responsible for generating the
`Expression` to also communicate from which `ts.SourceFile` the
generated `Expression` would be imported, precluding the need for module
resolution down the road.
PR Close#40948
The import graph scans source files for its import and export statements
to extract the source files that it imports/exports. Such statements
contain a module specifier string and this module specifier used to be
resolved to the actual source file using an explicit module resolution
step. This is especially expensive in incremental rebuilds, as the
module resolution cache has not been primed during program creation
(assuming that the incremental program was able to reuse the module
resolution results from a prior compilation). This meant that all module
resolution requests would have to hit the filesystem, which is
relatively slow.
This commit is able to replace the module resolution with TypeScript's
bound symbol of the module specifier. This symbol corresponds with the
`ts.SourceFile` that is being imported/exported, which is exactly what
the import graph was interested in. As a result, no filesystem accesses
are done anymore.
PR Close#40948
This change marks all relevant define* callsites as pure, causing the compiler to
emmit either @__PURE__ or @pureOrBreakMyCode annotation based on whether we are
compiling code annotated for closure or terser.
This change is needed in g3 where we don't run build optimizer but we
need the code to be annotated for the closure compiler.
Additionally this change allows for simplification of CLI and build optimizer as they
will no longer need to rewrite the generated code (there are still other places where
a build optimizer rewrite will be necessary so we can't remove it, we can only simplify it).
PR Close#41096
In Angular programs, changing a file may require other files to be
emitted as well due to implicit NgModule dependencies. For example, if
the selector of a directive is changed then all components that have
that directive in their compilation scope need to be recompiled, as the
change of selector may affect the directive matching results.
Until now, the compiler solved this problem using a single dependency
graph. The implicit NgModule dependencies were represented in this
graph, such that a changed file would correctly also cause other files
to be re-emitted. This approach is limited in a few ways:
1. The file dependency graph is used to determine whether it is safe to
reuse the analysis data of an Angular decorated class. This analysis
data is invariant to unrelated changes to the NgModule scope, but
because the single dependency graph also tracked the implicit
NgModule dependencies the compiler had to consider analysis data as
stale far more often than necessary.
2. It is typical for a change to e.g. a directive to not affect its
public API—its selector, inputs, outputs, or exportAs clause—in which
case there is no need to re-emit all declarations in scope, as their
compilation output wouldn't have changed.
This commit implements a mechanism by which the compiler is able to
determine the impact of a change by comparing it to the prior
compilation. To achieve this, a new graph is maintained that tracks all
public API information of all Angular decorated symbols. During an
incremental compilation this information is compared to the information
that was captured in the most recently succeeded compilation. This
determines the exact impact of the changes to the public API, which
is then used to determine which files need to be re-emitted.
Note that the file dependency graph remains, as it is still used to
track the dependencies of analysis data. This graph does no longer track
the implicit NgModule dependencies, which allows for better reuse of
analysis data.
These changes also fix a bug where template type-checking would fail to
incorporate changes made to a transitive base class of a
directive/component. This used to be a problem because transitive base
classes were not recorded as a transitive dependency in the file
dependency graph, such that prior type-check blocks would erroneously
be reused.
This commit also fixes an incorrectness where a change to a declaration
in NgModule `A` would not cause the declarations in NgModules that
import from NgModule `A` to be re-emitted. This was intentionally
incorrect as otherwise the performance of incremental rebuilds would
have been far worse. This is no longer a concern, as the compiler is now
able to only re-emit when actually necessary.
Fixes#34867Fixes#40635Closes#40728
PR Close#40947
For certain generated function calls, the compiler emits a 'PURE' annotation
which informs Terser (the optimizer) about the purity of a specific function
call. This commit expands that system to produce a new Closure-specific
'pureOrBreakMyCode' annotation when targeting the Closure optimizer instead
of Terser.
PR Close#41021
The current logic in the compiler is to bail when there are errors when
parsing a template into an HTML AST or when there are errors in the i18n
metadata. As a result, a template with these types of parse errors
_will not have any information for the language service_. This is because we
never attempt to conver the HTML AST to a template AST in these
scenarios, so there are no template AST nodes for the language service
to look at for information. In addition, this also means that the errors
are never displayed in the template to the user because there are no
nodes to map the error to.
This commit adds an option to the template parser to temporarily ignore
the html parse and i18n meta errors and always perform the template AST
conversion. At the end, the i18n and HTML parse errors are appended to
the returned errors list. While this seems risky, it at least provides
us with more information than we had before (which was 0) and it's only
done in the context of the language service, when the compiler is
configured to use poisoned data (HTML parse and i18n meta errors can be
interpreted as a "poisoned" template).
fixes angular/vscode-ng-language-service#1140
PR Close#41068
1. The error function throws, so no code after it is reachable.
2. Some switch statements are exhaustive, so no code after them are reachable.
PR Close#40984
Ngcc uses the `paths` property to compute the potential base-paths
for packages that are being processed. If the `paths` contain a wildcard
`*` within a path segment, ngcc was not finding the base-path correctly.
Now when a wildcard is found, there is an additional search to look for
paths that might match the wildcard.
Fixes#41014
PR Close#41033
Previously, when `ngcc` encountered an entry-point with a format-path
that pointed to a non-existing or empty file it would throw an error and
stop processing the remaining tasks.
In the past, we used to ignore such format-paths and continue processing
the rest of the tasks ([see code][1]). This was changed to a hard
failure in 2954d1b5ca. Looking at the code
history, the reason for changing the behavior was an (incorrect)
assumption that the condition could not fail. This assumption failed to
take into account the case where a 3rd-party library has an invalid
format-path in its `package.json`. This is an issue with the library,
but it should not prevent `ngcc` from processing other
packages/entry-points/formats.
This commit fixes this by reporting the task as failed but not throwing
an error, thus allowing `ngcc` to continue processing other tasks.
[1]: https://github.com/angular/angular/blob/3077c9a1f89c5bd75fb96c16e/packages/compiler-cli/ngcc/src/main.ts#L124Fixes#40965
PR Close#40985
Some tools (such as Language Server and ng-packagr) only care about
the processed typings generated by ngcc. Forcing these tools to process
the JavaScript files as well has two disadvantages:
First, unnecessary work is being done, which is time consuming.
But more importantly, it is not always possible to know how the final bundling
tools will want the processed JavaScript to be configured. For example,
the CLI would prefer the `--create-ivy-entry-points` option but this would
break non-CLI build tooling.
This commit adds a new option (`--typings-only` on the command line, and
`typingsOnly` via programmatic API) that instructs ngcc to only render changes
to the typings files for the entry-points that it finds, and not to write any
JavaScript files.
In order to process the typings, a JavaScript format will need to be analysed, but
it will not be rendered to disk. When using this option, it is best to offer ngcc a
wide range of possible JavaScript formats to choose from, and it will use the
first format that it finds. Ideally you would configure it to try the `ES2015` FESM
format first, since this will be the most performant.
Fixes#40969
PR Close#40976
With this change we drop support for zone.js 0.10.x.
This is needed because in version 12 the CLI will only work with `~0.11.4`. See angular/angular-cli#20034.
BREAKING CHANGE:
Minimum supported `zone.js` version is `0.11.4`
PR Close#40823
This commit moves a constant which is affected by a g3 sync patch into a
separate file. This way, changes to the rest of the compiler codebase have
no chance of conflicting with the patched code.
PR Close#40950
This is a pre-requisite for #40360. Given the following template which has a listener
that references a variable from a parent template (`name`):
```
<ng-template let-name="name">
<button (click)="hello(name)"></button>
</ng-template>
```
We generate code that looks that looks like. Note how we access `name` through `ctx`:
```js
function template(rf, ctx) {
if (rf & 1) {
const r0 = ɵɵgetCurrentView();
ɵɵelementStart(0, "button", 2);
ɵɵlistener("click", function() {
ɵɵrestoreView(r0);
const name_r0 = ctx.name; // Note the `ctx.name` access here.
const ctx_r1 = ɵɵnextContext();
return ctx_r1.log(name_r0);
});
ɵɵelementEnd();
}
}
```
This works fine at the moment, because the template context object can't be changed after creation.
The changes in #40360 allow for the object to be changed, which means that the `ctx` reference
inside the listener will be out of date, because it was bound during creation mode.
This PR aims to address the issue by accessing the context inside listeners through the saved
view reference. With the new code, the generated code from above will look as follows:
```js
function template(rf, ctx) {
if (rf & 1) {
const r0 = ɵɵgetCurrentView();
ɵɵelementStart(0, "button", 2);
ɵɵlistener("click", function() {
const restoredCtx = ɵɵrestoreView(r0);
const name_r0 = restoredCtx.name;
const ctx_r1 = ɵɵnextContext();
return ctx_r1.log(name_r0);
});
ɵɵelementEnd();
}
}
```
PR Close#40833
Our approach for handling cyclic imports results in code that is
not easy to tree-shake, so it is not suitable for publishing in a
library.
When compiling in partial compilation mode, we are targeting
such library publication, so we now create a fatal diagnostic
error instead of trying to handle the cyclic import situation.
Closes#40678
PR Close#40782
This commit implements creating of `ɵɵngDeclarePipe()` calls in partial
compilation, and processing of those calls in the linker and JIT compiler.
See #40677
PR Close#40803
This commit causes imports added by ngtsc's `ImportManager` to have their
TypeScript "original node" set to the generated `ts.ImportDeclaration`
statement.
In g3, the tsickle transformer runs after the Angular transformer and post-
processes Angular's compilation output. One of its post-processing tasks is
to transform generated imports and references to imported symbols from the
commonjs module system to the g3 module system. Part of this transformation
involves recognizing modules with specific metadata and altering references
to symbols from those modules accordingly.
Normally, tsickle can rely on TypeScript's binding for an imported symbol to
find its origin module and thus the correct metadata for the symbol. However
the Angular transform generates new synthetic imports which don't have such
binding information. Angular's imports are always namespace imports of the
form:
```
import * as qualifier 'module/specifier';
```
References to such an import are then of the form `qualifier.SymbolName`.
To process such imports properly, tsickle needs to be able to associate the
reference to `qualifier` in the expression `qualifer.SymbolName` with the
`ts.ImportDeclaration` statement that defines it. It expects to do this by
looking at the `ts.getOriginalNode()` for the `qualifier` reference, which
should be the `ts.ImportDeclaration`. This commit changes ngtsc's import
generation mechanism to set the original node on `qualifier` identifiers
according to this expectation.
This commit is not tested in the direct compiler tests, since:
1) there is no observable behavior externally from setting the original node
2) we don't have tests that intercept transformer operations (which could be
used to directly assert against the AST nodes)
3) tsickle's published version does not (yet) contain the g3-specific
transformations which rely on the original node and would thus allow the
behavior to be observed.
Instead, we rely on the g3 testing suite to validate the correctness of this
fix. Breaking this functionality would cause g3 compilation errors for
targets, since tsickle would be unable to transform imports correctly.
PR Close#40711
In 5c547675b11a24b16c20df1718583a0e7ed49cbd the `EventEmitter.subscribe`
API was extended with a new signature that allows the emitter's generic
type `T` to flow into the subscribe callback. This new signature removes
the need for the special `_outputHelper` function that used to be
emitted into TCBs when `strictOutputEventTypes`/`strictTemplates` is
enabled.
PR Close#40738
Produces a diagnostic when we cannot resolve a component's external style sheet or external template.
The previous behavior was to throw an exception, which crashed the
Language Service.
fixes angular/vscode-ng-language-service#1079
PR Close#40660
The `AsyncPipe.transform<T>(emitter)` method must infer the `T`
type from the `emitter` parameter. Since we changed the `AsyncPipe`
to expect a `Subscribable<T>` rather than `Observable<T>` the
`EventEmitter.subscribe()` method needs to have a tighter signature.
Otherwise TypeScript struggles to infer the type and ends up making
it `unknown`.
Fixes#40637
PR Close#40644
The `TemplateTypeChecker.overrideComponentTemplate` operation was originally
conceived as a "fast path" for the Language Service to react to a template
change without needing to go through a full incremental compilation step. It
served this purpose until the previous commit, which switches the LS to use
the new resource-only incremental change operation provided by `NgCompiler`.
`overrideComponentTemplate` is now no longer utilized, and is known to have
several hard-to-overcome issues that prevent it from being useful in any
other situations. As such, this commit removes it entirely.
PR Close#40585
Normally the template parsing operation normalizes all template line endings
to '\n' only. This normalization operation causes source mapping errors when
the original template uses '\r\n' line endings.
The compiler already parses templates again to create a "diagnostic"
template AST with accurate source maps, to avoid other parsing issues that
affect source map accuracy. This commit configures this diagnostic parse to
also preserve line endings.
PR Close#40597
If the template parse option `leadingTriviaChars` is configured to
consider whitespace as trivia, any trailing whitespace of an element
would be considered as leading trivia of the subsequent element, such
that its `start` span would start _after_ the whitespace. This means
that the start span cannot be used to mark the end of the current
element, as its trailing whitespace would then be included in its span.
Instead, the full start of the subsequent element should be used.
To harden the tests that for the Ivy parser, the test utility `parseR3`
has been adjusted to use the same configuration for `leadingTriviaChars`
as would be the case in its production counterpart `parseTemplate`. This
uncovered another bug in offset handling of the interpolation parser,
where the absolute offset was computed from the start source span
(which excludes leading trivia) whereas the interpolation expression
would include the leading trivia. As such, the absolute offset now also
uses the full start span.
Fixes#39148
PR Close#40513
This commit adds a new `IncrementalResourceCompilationTicket` which reuses
an existing `NgCompiler` instance and updates it to optimally process
template-only and style-only changes. Performing this update involves both
instructing `DecoratorHandler`s to react to the resource changes, as well as
invalidating `TemplateTypeChecker` state for the component(s) in question.
That way, querying the `TemplateTypeChecker` will trigger new TCB generation
for the changed template(s).
PR Close#40561
To prepare for the optimization of template-only changes, this commit
refactors the `ComponentDecoratorHandler`'s handling of template parsing.
Previously, templates were extracted from the raw decorator metadata and
parsed in a single operation.
To better handle incremental template updates, this commit splits this
operation into a "declaration" step where the template info is extracted
from the decorator metadata, and a "parsing" step where the declared
template is read and parsed. This allows for re-reading and re-parsing of
the declared template at a future point, using the same template declaration
extracted from the decorator.
PR Close#40561
Previously, the incremental flow for NgCompiler was simple: when creating a
new NgCompiler instance, the consumer could pass state from a previous
compilation, which would cause the new compilation to be performed
incrementally. "Local" information about TypeScript files which had not
changed would be passed from the old compilation to the new and reused,
while "global" information would always be recalculated.
However, this flow could be made more efficient in certain cases, such as
when no TypeScript files are changed in a new compilation. In this case,
_all_ information extracted during the first compilation is reusable. Doing
this involves reusing the previous `NgCompiler` instance (the container for
such global information) and updating it, instead of creating a new one for
the next compilation. This approach works cleanly, but complicates the
lifecycle of `NgCompiler`.
To prevent consumers from having to deal with the mechanics of reuse vs
incremental steps of `NgCompiler`, a new `CompilationTicket` mechanism is
added in this commit. Consumers obtain a `CompilationTicket` via one of
several code paths depending on the nature of the incoming compilation, and
use the `CompilationTicket` to obtain an `NgCompiler` instance. This
instance may be a fresh compilation, a new `NgCompiler` for an incremental
compilation, or an existing `NgCompiler` that's been updated to optimally
process a resource-only change. Consumers can use the new `NgCompiler`
without knowledge of its provenance.
PR Close#40561
Previously, we were naïvely checking whether a function name was a partial linker
declaration call by testing the map of linkers with `linkers[name]`. Since
`linkers` was a plain object, it also matched function names like `toString`!
This has been refactored as a `Map` to avoid the problem.
PR Close#40563
This PR adds a way for the language server to retrieve compiler options
diagnostics via `languageService.getCompilerOptionsDiagnostics()`.
This will be used by the language server to show a prompt in the editor if
users don't have `strict` or `fullTemplateTypeCheck` turned on.
Ref https://github.com/angular/vscode-ng-language-service/issues/1053
PR Close#40423
The compliance test runner has various macros that process the
expectation files before actually checking their contents. Among those
macros are i18n helpers, which uses a global message counter to be able
to uniquely identify ICU variables.
Because of the global nature of this message index, it was susceptible
to ordering issues which could result in flaky tests, although it failed
very infrequently.
This commit resets the global message counter before applying the macros.
As a result of this change an expectation file had to be updated; this
is actually a bug fix as said test used to fail if run in isolation (if
`focusTest: true` was set for that particular testcase).
PR Close#40529
When a source-map has an inline source, any source-map linked from
that source should only be loaded if itself is also inline; it should not
attempt to load a source-map from the file-system. Otherwise we can
find ourselves with inadvertent infinite cyclic dependencies.
For example, if a transpiler takes a file (e.g. index.js) and generates
a new file overwriting the original file - capturing the original
source inline in the new source-map (index.js.map) - the source
file loader might read the inline original file (also index.js) and
then try to load the `index.js.map` file from disk - ad infinitum.
Note that the first call to `loadSourceFile()` is special, since you can
pass in the source-file and source-map contents directly as in-memory
strrngs. This is common if the transpiler has just generated these and has
not yet written them to disk.
When the contents are passed into `loadSourceFile()` directly, they are
not treated as "inline" for the purposes described above since there is
no chance of these "in-memory" source and source-map contents being caught
up in a cyclic dependency.
Fixes#40408
PR Close#40435
JoostK
Pete Bacon Darwin
Misko Hevery
Alex Rickabaugh
Igor Minar
Andrew Scott
George Kalpakas
Alan Agius
Chellappan
Kristiyan Kostadinov
Zach Arend
Joey Perrott
Keen Yee Liau
twerske