`NgCompiler` previously had a notion of the "next" `ts.Program`, which
served two purposes:
* it allowed a client using the `ts.createProgram` API to query for the
latest program produced by the previous `NgCompiler`, as a starting
point for building the _next_ program that incorporated any new user
changes.
* it allowed the old `NgCompiler` to be queried for the `ts.Program` on
which all prior state is based, which is needed to compute the delta
from the new program to ultimately determine how much of the prior
state can be reused.
This system contained a flaw: it relied on the `NgCompiler` knowing when
the `ts.Program` would be changed. This works fine for changes that
originate in `NgCompiler` APIs, but a client of the `TemplateTypeChecker`
may use that API in ways that create new `ts.Program`s without the
`NgCompiler`'s knowledge. This caused the `NgCompiler`'s concept of the
"next" program to get out of sync, causing incorrectness in future
incremental analysis.
This refactoring cleans up the compiler's `ts.Program` management in
several ways:
* `TypeCheckingProgramStrategy`, the API which controls `ts.Program`
updating, is renamed to the `ProgramDriver` and extracted to a separate
ngtsc package.
* It loses its responsibility of determining component shim filenames. That
functionality now lives exclusively in the template type-checking package.
* The "next" `ts.Program` concept is renamed to the "current" program, as
the "next" name was misleading in several ways.
* `NgCompiler` now wraps the `ProgramDriver` used in the
`TemplateTypeChecker` to know when a new `ts.Program` is created,
regardless of which API drove the creation, which actually fixes the bug.
PR Close#41291
This commit changes the partial compilation so that it outputs declarations
rather than definitions for injectables.
The JIT compiler and the linker are updated to be able to handle these
new declarations.
PR Close#41316
The other similar interfaces were renamed in https://github.com/angular/angular/pull/41119,
but this one was left since it had existed before Ivy. It looks like the interface was
never actually exposed on npm so it is safe to rename this one too.
PR Close#41316
Currently, we throw a FatalDiagnosticError when we fail to load a resource
(`templateUrl` or `styleUrl`) at various stages in the compiler. This prevents
analysis of the component from completing. This will result in in users not being
able to get any information in the component template when there is a missing
`styleUrl`, for example.
This commit simply tracks the diagnostic, marks the component as poisoned, and
continues merrily along. Environments configured to use poisoned data
(like the language service) will then be able to use other information from the analysis.
Fixes https://github.com/angular/vscode-ng-language-service/issues/1241
PR Close#41403
Currently, fs-extra is used to delete a directory recursively, but this is already available in native Node.JS. Hence, making this dependency redundant.
See: https://nodejs.org/docs/latest-v12.x/api/fs.html
PR Close#41445
This change introduces a new hook on the `ResourceHost` interface named `transformResource`.
Resource transformation allows both external and inline resources to be transformed prior to
compilation by the AOT compiler. This provides support for tooling integrations to enable
features such as preprocessor support for inline styles.
Only style resources are currently supported. However, the infrastructure is in place to add
template support in the future.
PR Close#41307
Adds perf tracing for the public methods in LanguageService. If the log level is verbose or higher,
trace performance results to the tsServer logger. This logger is implemented on the extension side
in angular/vscode-ng-language-service.
PR Close#41319
This enumeration will now start to appear in publicly facing code,
as part of declarations, so we remove the R3 to make it less specific
to the internal name for the Ivy renderer/compiler.
PR Close#41231
Each of the annotations had its own function for doing this, and those
methods were generally employing spread operators that could allow
unwanted properties to leak into the factory metadata object.
This commit supplies a shared function `toFactoryMetadata()` that
avoids this spread of properties into the returned function.
PR Close#41231
Now that other values were removed from `R3ResolvedDependencyType`,
its meaning can now be inferred from the other properties in the
`R3DeclareDependencyMetadata` type. This commit removes this enum
and updates the code to work without it.
PR Close#41231
When `ɵngDeclareInjector()` was implemented, the `factory` was moved
out to the `ɵfac` static property on the class. This check was not updated.
PR Close#41231
This instruction was created to work around a problem with injecting a
`ChangeDetectorRef` into a pipe. See #31438. This fix required special
metadata for when the thing being injected was a `ChangeDetectorRef`.
Now this is handled by adding a flag `InjectorFlags.ForPipe` to the
`ɵɵdirectiveInject()` call, which avoids the need to special test_cases
`ChangeDetectorRef` in the generated code.
PR Close#41231
This commit changes the partial compilation so that it outputs declaration
calls rather than compiled factory functions.
The JIT compiler and the linker are updated to be able to handle these
new declarations.
PR Close#41231
A previous commit implemented a streamlined performance metric reporting
system for the compiler-cli, controlled via the compiler option
`tracePerformance`.
This commit adds a custom Bazel flag rule //packages/compiler-cli:ng_perf
to the repository, and wires it through to the `ng_module` implementation
such that if the flag is set, `ng_module` will produce perf results as part
of the build. The underlying mechanism of `//:ng_perf` is not exported from
`@angular/bazel` as a public rule that consumers can use, so there is little
risk of accidental dependency on the contents of these perf traces.
An alias is added so that `--ng_perf` is a Bazel flag which works in our
repository.
PR Close#41125
ngtsc has an internal performance tracing package, which previously has not
really seen much use. It used to track performance statistics on a very
granular basis (microseconds per actual class analysis, for example). This
had two problems:
* it produced voluminous amounts of data, complicating the analysis of such
results and providing dubious value.
* it added nontrivial overhead to compilation when used (which also affected
the very performance of the operations being measured).
This commit replaces the old system with a streamlined performance tracing
setup which is lightweight and designed to be always-on. The new system
tracks 3 metrics:
* time taken by various phases and operations within the compiler
* events (counters) which measure the shape and size of the compilation
* memory usage measured at various points of the compilation process
If the compiler option `tracePerformance` is set, the compiler will
serialize these metrics to a JSON file at that location after compilation is
complete.
PR Close#41125
TypeScript 4.2 has changed its emitted syntax for synthetic constructors
when using `downlevelIteration`, which affects ES5 bundles that have
been downleveled from ES2015 bundles. This is typically the case for UMD
bundles in the APF spec, as they are generated by downleveling the
ESM2015 bundle into ES5. ngcc needs to detect the new syntax in order to
correctly identify synthesized constructor functions in ES5 bundles.
Fixes#41298
PR Close#41305
The Ivy Language Service uses the compiler's template type-checking engine,
which honors the configuration in the user's tsconfig.json. We recommend
that users upgrade to `strictTemplates` mode in their projects to take
advantage of the best possible type inference, and thus to have the best
experience in Language Service.
If a project is not using `strictTemplates`, then the compiler will not
leverage certain type inference options it has. One case where this is very
noticeable is the inference of let- variables for structural directives that
provide a template context guard (such as NgFor). Without `strictTemplates`,
these guards will not be applied and such variables will be inferred as
'any', degrading the user experience within Language Service.
This is working as designed, since the Language Service _should_ reflect
types exactly as the compiler sees them. However, the View Engine Language
Service used its own type system that _would_ infer these types even when
the compiler did not. As a result, it's confusing to some users why the
Ivy Language Service has "worse" type inference.
To address this confusion, this commit implements a suggestion diagnostic
which is shown in the Language Service for variables which could have been
narrowed via a context guard, but the type checking configuration didn't
allow it. This should make the reason why variables receive the 'any' type
as well as the action needed to improve the typings much more obvious,
improving the Language Service experience.
Fixes angular/vscode-ng-language-service#1155
Closes#41042
PR Close#41072
The `ɵɵInjectorDef` interface is internal and should not be published publicly
as part of libraries. This commit updates the compiler to render an opaque
type, `ɵɵInjectorDeclaration`, for this instead, which appears in the typings
for compiled libraries.
PR Close#41119
Th `ɵɵFactoryDef` type will appear in published libraries, via their typings
files, to describe what type dependencies a DI factory has. The parameters
on this type are used by tooling such as the Language Service to understand
the DI dependencies of the class being created by the factory.
This commit moves the type to the `public_definitions.ts` file alongside
the other types that have a similar role, and it renames it to `ɵɵFactoryDeclaration`
to align it with the other declaration types such as `ɵɵDirectiveDeclaration`
and so on.
PR Close#41119
These types are only used in the generated typings files to provide
information to the Angular compiler in order that it can compile code
in downstream libraries and applications.
This commit aliases these types to `unknown` to avoid exposing the
previous alias types such as `ɵɵDirectiveDef`, which are internal to
the compiler.
PR Close#41119
This commit fixes the behavior when creating a type constructor for a directive when the following
conditions are met.
1. The directive has bound generic parameters.
2. Inlining is not available. (This happens for language service compiles).
Previously, we would throw an error saying 'Inlining is not supported in this environment.' The
compiler would stop type checking, and the developer could lose out on getting errors after the
compiler gives up.
This commit adds a useInlineTypeConstructors to the type check config. When set to false, we use
`any` type for bound generic parameters to avoid crashing. When set to true, we inline the type
constructor when inlining is required.
Addresses #40963
PR Close#41043
For the tests in //packages/compiler-cli/src/ngtsc/typecheck, this
commits uses a `TypeCheckFile` for the environment, rather than a
`FakeEnvironment`. Using a real environment gives us more flexibility
with testing.
PR Close#41043
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