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
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
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
As a performance optimization, this commit splits the single
__ngtypecheck__.ts file which was previously added to the user's program as
a container for all template type-checking code into multiple .ngtypecheck
shim files, one for each original file in the user's program.
In larger applications, the generation, parsing, and checking of this single
type-checking file was a huge performance bottleneck, with the file often
exceeding 1 MB in text content. Particularly in incremental builds,
regenerating this single file for the entire application proved especially
expensive.
This commit introduces a new strategy for template type-checking code which
makes use of a new interface, the `TypeCheckingProgramStrategy`. This
interface abstracts the process of creating a new `ts.Program` to type-check
a particular compilation, and allows the mechanism there to be kept separate
from the more complex logic around dealing with multiple .ngtypecheck files.
A new `TemplateTypeChecker` hosts that logic and interacts with the
`TypeCheckingProgramStrategy` to actually generate and return diagnostics.
The `TypeCheckContext` class, previously the workhorse of template type-
checking, is now solely focused on collecting and generating type-checking
file contents.
A side effect of implementing the new `TypeCheckingProgramStrategy` in this
way is that the API is designed to be suitable for use by the Angular
Language Service as well. The LS also needs to type-check components, but
has its own method for constructing a `ts.Program` with type-checking code.
Note that this commit does not make the actual checking of templates at all
_incremental_ just yet. That will happen in a future commit.
PR Close#36211
Shim generation was built on a lie.
Shims are files added to the program which aren't original files authored by
the user, but files authored effectively by the compiler. These fall into
two categories: files which will be generated (like the .ngfactory shims we
generate for View Engine compatibility) as well as files used internally in
compilation (like the __ng_typecheck__.ts file).
Previously, shim generation was driven by the `rootFiles` passed to the
compiler as input. These are effectively the `files` listed in the
`tsconfig.json`. Each shim generator (e.g. the `FactoryGenerator`) would
examine the `rootFiles` and produce a list of shim file names which it would
be responsible for generating. These names would then be added to the
`rootFiles` when the program was created.
The fatal flaw here is that `rootFiles` does not always account for all of
the files in the program. In fact, it's quite rare that it does. Users don't
typically specify every file directly in `files`. Instead, they rely on
TypeScript, during program creation, starting with a few root files and
transitively discovering all of the files in the program.
This happens, however, during `ts.createProgram`, which is too late to add
new files to the `rootFiles` list.
As a result, shim generation was only including shims for files actually
listed in the `tsconfig.json` file, and not for the transitive set of files
in the user's program as it should.
This commit completely rewrites shim generation to use a different technique
for adding files to the program, inspired by View Engine's shim generator.
In this new technique, as the program is being created and `ts.SourceFile`s
are being requested from the `NgCompilerHost`, shims for those files are
generated and a reference to them is patched onto the original file's
`ts.SourceFile.referencedFiles`. This causes TS to think that the original
file references the shim, and causes the shim to be included in the program.
The original `referencedFiles` array is saved and restored after program
creation, hiding this little hack from the rest of the system.
The new shim generation engine differentiates between two kinds of shims:
top-level shims (such as the flat module entrypoint file and
__ng_typecheck__.ts) and per-file shims such as ngfactory or ngsummary
files. The former are included via `rootFiles` as before, the latter are
included via the `referencedFiles` of their corresponding original files.
As a result of this change, shims are now correctly generated for all files
in the program, not just the ones named in `tsconfig.json`.
A few mitigating factors prevented this bug from being realized until now:
* in g3, `files` does include the transitive closure of files in the program
* in CLI apps, shims are not really used
This change also makes use of a novel technique for associating information
with source files: the use of an `NgExtension` `Symbol` to patch the
information directly onto the AST object. This is used in several
circumstances:
* For shims, metadata about a `ts.SourceFile`'s status as a shim and its
origins are held in the extension data.
* For original files, the original `referencedFiles` are stashed in the
extension data for later restoration.
The main benefit of this technique is a lot less bookkeeping around `Map`s
of `ts.SourceFile`s to various kinds of data, which need to be tracked/
invalidated as part of incremental builds.
This technique is based on designs used internally in the TypeScript
compiler and is serving as a prototype of this design in ngtsc. If it works
well, it could have benefits across the rest of the compiler.
PR Close#36211
In Ivy, Angular decorators are compiled into static fields that are
inserted into a class declaration in a TypeScript transform. When
targeting Closure compiler such fields need to be annotated with
`@nocollapse` to prevent them from being lifted from a static field into
a variable, as that would prevent the Ivy runtime from being able to
find the compiled definitions.
Previously, there was a bug in TypeScript where synthetic comments added
in a transform would not be emitted at all, so as a workaround a global
regex-replace was done in the emit's `writeFile` callback that would add
the `@nocollapse` annotation to all static Ivy definition fields. This
approach is no longer possible when ngtsc is running as TypeScript
plugin, as a plugin cannot control emit behavior.
The workaround is no longer necessary, as synthetic comments are now
properly emitted, likely as of
https://github.com/microsoft/TypeScript/pull/22141 which has been
released with TypeScript 2.8.
This change is required for running ngtsc as TypeScript plugin in
Bazel's `ts_library` rule, to move away from the custom `ngc_wrapped`
approach.
Resolves FW-1952
PR Close#35932
This commit moves the calculation of `ignoreFiles` - the set of files to be
ignored by a consumer of the `NgCompiler` API - from its `prepareEmit`
operation to its initialization. It's now available as a field on
`NgCompiler`.
This will allow a consumer to skip gathering diagnostics for `ignoreFiles`
as well as skip emit.
PR Close#34792
Previously, NgtscProgram lived in the main @angular/compiler-cli package
alongside the legacy View Engine compiler. As a result, the main package
depended on all of the ngtsc internal packages, and a significant portion of
ngtsc logic lived in NgtscProgram.
This commit refactors NgtscProgram and moves the main logic of compilation
into a new 'core' package. The new package defines a new API which enables
implementers of TypeScript compilers (compilers built using the TS API) to
support Angular transpilation as well. It involves a new NgCompiler type
which takes a ts.Program and performs Angular analysis and transformations,
as well as an NgCompilerHost which wraps an input ts.CompilerHost and adds
any extra Angular files.
Together, these two classes are used to implement a new NgtscProgram which
adapts the legacy api.Program interface used by the View Engine compiler
onto operations on the new types. The new NgtscProgram implementation is
significantly smaller and easier to reason about.
The new NgCompilerHost replaces the previous GeneratedShimsHostWrapper which
lived in the 'shims' package.
A new 'resource' package is added to support the HostResourceLoader which
previously lived in the outer compiler package.
As a result of the refactoring, the dependencies of the outer
@angular/compiler-cli package on ngtsc internal packages are significantly
trimmed.
This refactoring was driven by the desire to build a plugin interface to the
compiler so that tsc_wrapped (another consumer of the TS compiler APIs) can
perform Angular transpilation on user request.
PR Close#34887
Previously, the template type-checker would always construct a generic
template context type with correct bounds, even when strictTemplates was
disabled. This meant that type-checking of expressions involving that type
was stricter than View Engine.
This commit introduces a 'strictContextGenerics' flag which behaves
similarly to other 'strictTemplates' flags, and switches the inference of
generic type parameters on the component context based on the value of this
flag.
PR Close#34649
Previously, it was required that both `fullTemplateTypeCheck` and
`strictTemplates` had to be enabled for strict mode to be enabled. This
is strange, as `strictTemplates` implies `fullTemplateTypeCheck`. This
commit makes setting the `fullTemplateTypeCheck` flag optional so that
strict mode can be enabled by just setting `strictTemplates`.
PR Close#34195
It is now an error if '"fullTemplateTypeCheck"' is disabled while
`"strictTemplates"` is enabled, as enabling the latter implies that the
former is also enabled.
PR Close#34195
In Ivy's template type checker, type constructors are created for all
directive types to allow for accurate type inference to work. The type
checker has two strategies for dealing with such type constructors:
1. They can be emitted local to the type check block/type check file.
2. They can be emitted as static `ngTypeCtor` field into the directive
itself.
The first strategy is preferred, as it avoids having to update the
directive type which would cause a more expensive rebuild. However, this
strategy is not suitable for directives that have constrained generic
types, as those constraints would need to be present on the local type
constructor declaration. This is not trivial, as it requires that any
type references within a type parameter's constraint are imported into
the local context of the type check block.
For example, lets consider the `NgForOf` directive from '@angular/core'
looks as follows:
```typescript
import {NgIterable} from '@angular/core';
export class NgForOf<T, U extends NgIterable<T>> {}
```
The type constructor will then have the signature:
`(o: Pick<i1.NgForOf<T, U>, 'ngForOf'>) => i1.NgForOf<T, U>`
Notice how this refers to the type parameters `T` and `U`, so the type
constructor needs to be emitted into a scope where those types are
available, _and_ have the correct constraints.
Previously, the template type checker would detect the situation where a
type parameter is constrained, and would emit the type constructor
using strategy 2; within the directive type itself. This approach makes
any type references within the generic type constraints lexically
available:
```typescript
export class NgForOf<T, U extends NgIterable<T>> {
static ngTypeCtor<T = any, U extends NgIterable<T> = any>
(o: Pick<NgForOf<T, U>, 'ngForOf'>): NgForOf<T, U> { return null!; }
}
```
This commit introduces the ability to emit a type parameter with
constraints into a different context, under the condition that it can
be imported from an absolute module. This allows a generic type
constructor to be emitted into a type check block or type check file
according to strategy 1, as imports have been generated for all type
references within generic type constraints. For example:
```typescript
import * as i0 from '@angular/core';
import * as i1 from '@angular/common';
const _ctor1: <T = any, U extends i0.NgIterable<T> = any>
(o: Pick<i1.NgForOf<T, U>, 'ngForOf'>) => i1.NgForOf<T, U> = null!;
```
Notice how the generic type constraint of `U` has resulted in an import
of `@angular/core`, and the `NgIterable` is transformed into a qualified
name during the emitting process.
Resolves FW-1739
PR Close#34021
Angular View Engine uses global knowledge to compile the following code:
```typescript
export class Base {
constructor(private vcr: ViewContainerRef) {}
}
@Directive({...})
export class Dir extends Base {
// constructor inherited from base
}
```
Here, `Dir` extends `Base` and inherits its constructor. To create a `Dir`
the arguments to this inherited constructor must be obtained via dependency
injection. View Engine is able to generate a correct factory for `Dir` to do
this because via metadata it knows the arguments of `Base`'s constructor,
even if `Base` is declared in a different library.
In Ivy, DI is entirely a runtime concept. Currently `Dir` is compiled with
an ngDirectiveDef field that delegates its factory to `getInheritedFactory`.
This looks for some kind of factory function on `Base`, which comes up
empty. This case looks identical to an inheritance chain with no
constructors, which works today in Ivy.
Both of these cases will now become an error in this commit. If a decorated
class inherits from an undecorated base class, a diagnostic is produced
informing the user of the need to either explicitly declare a constructor or
to decorate the base class.
PR Close#34460
Adds a compilation error if the consumer tries to pass in an undecorated class into the `providers` of an `NgModule`, or the `providers`/`viewProviders` arrays of a `Directive`/`Component`.
PR Close#34460
This commit adds three previously missing validations to
NgModule.declarations:
1. It checks that declared classes are actually within the current
compilation.
2. It checks that declared classes are directives, components, or pipes.
3. It checks that classes are declared in at most one NgModule.
PR Close#34404
During TypeScript module resolution, a lot of filesystem requests are
done. This is quite an expensive operation, so a module resolution cache
can be used to speed up the process significantly.
This commit lets the Ivy compiler perform all module resolution with a
module resolution cache. Note that the module resolution behavior can be
changed with a custom compiler host, in which case that custom host
implementation is responsible for caching. In the case of the Angular
CLI a custom compiler host with proper module resolution caching is
already in place, so the CLI already has this optimization.
PR Close#34332
Previously, the compiler performed an incremental build by analyzing and
resolving all classes in the program (even unchanged ones) and then using
the dependency graph information to determine which .js files were stale and
needed to be re-emitted. This algorithm produced "correct" rebuilds, but the
cost of re-analyzing the entire program turned out to be higher than
anticipated, especially for component-heavy compilations.
To achieve performant rebuilds, it is necessary to reuse previous analysis
results if possible. Doing this safely requires knowing when prior work is
viable and when it is stale and needs to be re-done.
The new algorithm implemented by this commit is such:
1) Each incremental build starts with knowledge of the last known good
dependency graph and analysis results from the last successful build,
plus of course information about the set of files changed.
2) The previous dependency graph's information is used to determine the
set of source files which have "logically" changed. A source file is
considered logically changed if it or any of its dependencies have
physically changed (on disk) since the last successful compilation. Any
logically unchanged dependencies have their dependency information copied
over to the new dependency graph.
3) During the `TraitCompiler`'s loop to consider all source files in the
program, if a source file is logically unchanged then its previous
analyses are "adopted" (and their 'register' steps are run). If the file
is logically changed, then it is re-analyzed as usual.
4) Then, incremental build proceeds as before, with the new dependency graph
being used to determine the set of files which require re-emitting.
This analysis reuse avoids template parsing operations in many circumstances
and significantly reduces the time it takes ngtsc to rebuild a large
application.
Future work will increase performance even more, by tackling a variety of
other opportunities to reuse or avoid work.
PR Close#34288
Previously 'analyze' in the various `DecoratorHandler`s not only extracts
information from the decorators on the classes being analyzed, but also has
several side effects within the compiler:
* it can register metadata about the types involved in global metadata
trackers.
* it can register information about which .ngfactory symbols are actually
needed.
In this commit, these side-effects are moved into a new 'register' phase,
which runs after the 'analyze' step. Currently this is a no-op refactoring
as 'register' is always called directly after 'analyze'. In the future this
opens the door for re-use of prior analysis work (with only 'register' being
called, to apply the above side effects).
Also as part of this refactoring, the reification of NgModule scope
information into the incremental dependency graph is moved to the
`NgtscProgram` instead of the `TraitCompiler` (which now only manages trait
compilation and does not have other side effects).
PR Close#34288
Prior to this commit, the `IvyCompilation` tracked the state of each matched
`DecoratorHandler` on each class in the `ts.Program`, and how they
progressed through the compilation process. This tracking was originally
simple, but had grown more complicated as the compiler evolved. The state of
each specific "target" of compilation was determined by the nullability of
a number of fields on the object which tracked it.
This commit formalizes the process of compilation of each matched handler
into a new "trait" concept. A trait is some aspect of a class which gets
created when a `DecoratorHandler` matches the class. It represents an Ivy
aspect that needs to go through the compilation process.
Traits begin in a "pending" state and undergo transitions as various steps
of compilation take place. The `IvyCompilation` class is renamed to the
`TraitCompiler`, which manages the state of all of the traits in the active
program.
Making the trait concept explicit will support future work to incrementalize
the expensive analysis process of compilation.
PR Close#34288
The `ModuleWithProviders` type has an optional type parameter that
should be specified to indicate what NgModule class will be provided.
This enables the Ivy compiler to statically determine the NgModule type
from the declaration files. This type parameter will become required in
the future, however to aid in the migration the compiler will detect
code patterns where using `ModuleWithProviders` as return type is
appropriate, in which case it transforms the emitted .d.ts files to
include the generic type argument.
This should reduce the number of occurrences where `ModuleWithProviders`
is referenced without its generic type argument.
Resolves FW-389
PR Close#34235
This commit refactors the way the compiler transforms .d.ts files during
ngtsc builds. Previously the `IvyCompilation` kept track of a
`DtsFileTransformer` for each input file. Now, any number of
`DtsTransform` operations that need to be applied to a .d.ts file are
collected in the `DtsTransformRegistry`. These are then ran using a
single `DtsTransformer` so that multiple transforms can be applied
efficiently.
PR Close#34235
Now that `@angular/localize` can interpret multiple legacy message ids in the
metablock of a `$localize` tagged template string, this commit adds those
ids to each i18n message extracted from component templates, but only if
the `enableI18nLegacyMessageIdFormat` is not `false`.
PR Close#34135
For injectables, we currently generate a factory function in the
injectable def (prov) that delegates to the factory function in
the factory def (fac). It looks something like this:
```
factory: function(t) { return Svc.fac(t); }
```
The extra wrapper function is unnecessary since the args for
the factory functions are the same. This commit changes the
compiler to generate this instead:
```
factory: Svc.fac
```
Because we are generating less code for each injectable, we
should see some modest code size savings. AIO's main bundle
is about 1 KB smaller.
PR Close#34076
In ViewEngine we were only generating code for exported classes, however with Ivy we do it no matter whether the class has been exported or not. These changes add an extra flag that allows consumers to opt into the ViewEngine behavior. The flag works by treating non-exported classes as if they're set to `jit: true`.
Fixes#33724.
PR Close#33921
Previously, our incremental build system kept track of the changes between
the current compilation and the previous one, and used its knowledge of
inter-file dependencies to evaluate the impact of each change and emit the
right set of output files.
However, a problem arose if the compiler was not able to extract a
dependency graph successfully. This typically happens if the input program
contains errors. In this case the Angular analysis part of compilation is
never executed.
If a file changed in one of these failed builds, in the next build it
appears unchanged. This means that the compiler "forgets" to emit it!
To fix this problem, the compiler needs to know the set of changes made
_since the last successful build_, not simply since the last invocation.
This commit changes the incremental state system to much more explicitly
pass information from the previous to the next compilation, and in the
process to keep track of changes across multiple failed builds, until the
program can be analyzed successfully and the results of those changes
incorporated into the emit plan.
Fixes#32214
PR Close#33971
Due to the fact that Tsickle runs between analyze and transform phases in Angular, Tsickle may transform nodes (add comments with type annotations for Closure) that we captured during the analyze phase. As a result, some patterns where a function is returned from another function may trigger automatic semicolon insertion, which breaks the code (makes functions return `undefined` instead of a function). In order to avoid the problem, this commit updates the code to wrap all functions in some expression ("privders" and "viewProviders") in parentheses. More info can be found in Tsickle source code here: d797426257/src/jsdoc_transformer.ts (L1021)
PR Close#33609
The Ivy template type-checker is capable of inferring the type of a
structural directive (such as NgForOf<T>). Previously, this was done with
fullTemplateTypeCheck: true, even if strictTemplates was false. View Engine
previously did not do this inference, and so this causes breakages if the
type of the template context is not what the user expected.
In particular, consider the template:
```html
<div *ngFor="let user of users as all">
{{user.index}} out of {{all.length}}
</div>
```
As long as `users` is an array, this seems reasonable, because it appears
that `all` is an alias for the `users` array. However, this is misleading.
In reality, `NgForOf` is rendered with a template context that contains
both a `$implicit` value (for the loop variable `user`) as well as a
`ngForOf` value, which is the actual value assigned to `all`. The type of
`NgForOf`'s template context is `NgForContext<T>`, which declares `ngForOf`'s
type to be `NgIterable<T>`, which does not have a `length` property (due to
its incorporation of the `Iterable` type).
This commit stops the template type-checker from inferring template context
types unless strictTemplates is set (and strictInputTypes is not disabled).
Fixes#33527.
PR Close#33537
Previously, the ngtsc compiler attempted to reuse analysis work from the
previous program during an incremental build. To do this, it had to prove
that the work was safe to reuse - that no changes made to the new program
would invalidate the previous analysis.
The implementation of this had a significant design flaw: if the previous
program had errors, the previous analysis would be missing significant
information, and the dependency graph extracted from it would not be
sufficient to determine which files should be re-analyzed to fill in the
gaps. This often meant that the build output after an error was resolved
would be wholly incorrect.
This commit switches ngtsc to take a simpler approach to incremental
rebuilds. Instead of attempting to reuse prior analysis work, the entire
program is re-analyzed with each compilation. This is actually not as
expensive as one might imagine - analysis is a fairly small part of overall
compilation time.
Based on the dependency graph extracted during this analysis, the compiler
then can make accurate decisions on whether to emit specific files. A new
suite of tests is added to validate behavior in the presence of source code
level errors.
This new approach is dramatically simpler than the previous algorithm, and
should always produce correct results for a semantically correct program.s
Fixes#32388Fixes#32214
PR Close#33862
Previously, the compiler assumed that all TS files logically within a
project existed under one or more "root directories". If the TS compiler
option `rootDir` or `rootDirs` was set, they would dictate the root
directories in use, otherwise the current directory was used.
Unfortunately this assumption was unfounded - it's common for projects
without explicit `rootDirs` to import from files outside the current
working directory. In such cases the `LogicalProjectStrategy` would attempt
to generate imports into those files, and fail. This would lead to no
`ReferenceEmitStrategy` being able to generate an import, and end in a
compiler assertion failure.
This commit introduces a new strategy to use when there are no `rootDirs`
explicitly present, the `RelativePathStrategy`. It uses simpler, filesystem-
relative paths to generate imports, even to files above the current working
directory.
Fixes#33659Fixes#33562
PR Close#33828
Removes `ngBaseDef` from the compiler and any runtime code that was still referring to it. In the cases where we'd previously generate a base def we now generate a definition for an abstract directive.
PR Close#33264
The template type checking abilities of the Ivy compiler are far more
advanced than the level of template type checking that was previously
done for Angular templates. Up until now, a single compiler option
called "fullTemplateTypeCheck" was available to configure the level
of template type checking. However, now that more advanced type checking
is being done, new errors may surface that were previously not reported,
in which case it may not be feasible to fix all new errors at once.
Having only a single option to disable a large number of template type
checking capabilities does not allow for incrementally addressing newly
reported types of errors. As a solution, this commit introduces some new
compiler options to be able to enable/disable certain kinds of template
type checks on a fine-grained basis.
PR Close#33365
View Engine correctly infers the type of local refs to directives or to
<ng-template>s, just not to DOM nodes. This commit splits the
checkTypeOfReferences flag into two separate halves, allowing the compiler
to align with this behavior.
PR Close#33365
For elements that have a text attribute, it may happen that the element
is matched by a directive that consumes the attribute as an input. In
that case, the template type checker will validate the correctness of
the attribute with respect to the directive's declared type of the
input, which would typically be `boolean` for the `disabled` input.
Since empty attributes are assigned the empty string at runtime, the
template type checker would report an error for this template.
This commit introduces a strictness flag to help alleviate this
particular situation, effectively ignoring text attributes that happen
to be consumed by a directive.
PR Close#33365
During the creation of an Angular program in the compiler, a check is
done to verify whether the version of TypeScript is considered
supported, producing an error if it is not. This check was missing in
the Ivy compiler, so users may have ended up running an unsupported
TypeScript version inadvertently.
Resolves FW-1643
PR Close#33377
In View Engine, with fullTemplateTypeCheck mode disabled, the type of any
inferred based on the entity being referenced. This is a bug, since the
goal with fullTemplateTypeCheck: false is for Ivy and VE to be aligned in
terms of type inference.
This commit adds a 'checkTypeOfReference' flag in the TypeCheckingConfig
to control this inference, and sets it to false when fullTemplateTypeCheck
is disabled.
PR Close#33261
This commit refactors the aliasing system to support multiple different
AliasingHost implementations, which control specific aliasing behavior
in ngtsc (see the README.md).
A new host is introduced, the `PrivateExportAliasingHost`. This solves a
longstanding problem in ngtsc regarding support for "monorepo" style private
libraries. These are libraries which are compiled separately from the main
application, and depended upon through TypeScript path mappings. Such
libraries are frequently not in the Angular Package Format and do not have
entrypoints, but rather make use of deep import style module specifiers.
This can cause issues with ngtsc's ability to import a directive given the
module specifier of its NgModule.
For example, if the application uses a directive `Foo` from such a library
`foo`, the user might write:
```typescript
import {FooModule} from 'foo/module';
```
In this case, foo/module.d.ts is path-mapped into the program. Ordinarily
the compiler would see this as an absolute module specifier, and assume that
the `Foo` directive can be imported from the same specifier. For such non-
APF libraries, this assumption fails. Really `Foo` should be imported from
the file which declares it, but there are two problems with this:
1. The compiler would have to reverse the path mapping in order to determine
a path-mapped path to the file (maybe foo/dir.d.ts).
2. There is no guarantee that the file containing the directive is path-
mapped in the program at all.
The compiler would effectively have to "guess" 'foo/dir' as a module
specifier, which may or may not be accurate depending on how the library and
path mapping are set up.
It's strongly desirable that the compiler not break its current invariant
that the module specifier given by the user for the NgModule is always the
module specifier from which directives/pipes are imported. Thus, for any
given NgModule from a particular module specifier, it must always be
possible to import any directives/pipes from the same specifier, no matter
how it's packaged.
To make this possible, when compiling a file containing an NgModule, ngtsc
will automatically add re-exports for any directives/pipes not yet exported
by the user, with a name of the form: ɵngExportɵModuleNameɵDirectiveName
This has several effects:
1. It guarantees anyone depending on the NgModule will be able to import its
directives/pipes from the same specifier.
2. It maintains a stable name for the exported symbol that is safe to depend
on from code on NPM. Effectively, this private exported name will be a
part of the package's .d.ts API, and cannot be changed in a non-breaking
fashion.
Fixes#29361
FW-1610 #resolve
PR Close#33177
As a hack to get the Ivy compiler ngtsc off the ground, the existing
'allowEmptyCodegenFiles' option was used to control generation of ngfactory
and ngsummary shims during compilation. This option was selected since it's
enabled in google3 but never enabled in external projects.
As ngtsc is now mature and the role shims play in compilation is now better
understood across the ecosystem, this commit introduces two new compiler
options to control shim generation:
* generateNgFactoryShims controls the generation of .ngfactory shims.
* generateNgSummaryShims controls the generation of .ngsummary shims.
The 'allowEmptyCodegenFiles' option is still honored if either of the above
flags are not set explicitly.
PR Close#33256
Until now, the template type checker has not checked any of the event
bindings that could be present on an element, for example
```
<my-cmp
(changed)="handleChange($event)"
(click)="handleClick($event)"></my-cmp>
```
has two event bindings: the `change` event corresponding with an
`@Output()` on the `my-cmp` component and the `click` DOM event.
This commit adds functionality to the template type checker in order to
type check both kind of event bindings. This means that the correctness
of the bindings expressions, as well as the type of the `$event`
variable will now be taken into account during template type checking.
Resolves FW-1598
PR Close#33125
This commit fixes ngtsc's import generator to use the ReflectionHost when
looking through the exports of an ES module to find the export of a
particular declaration that's being imported. This is necessary because
some module formats like CommonJS have unusual export mechanics, and the
normal TypeScript ts.TypeChecker does not understand them.
This fixes an issue with ngcc + CommonJS where exports were not being
enumerated correctly.
FW-1630 #resolve
PR Close#33192
This commit introduces an internal config option of the template type
checker that allows to disable strict null checks of input bindings to
directives. This may be particularly useful when a directive is from a
library that is not compiled with `strictNullChecks` enabled.
Right now, strict null checks are enabled when `fullTemplateTypeCheck`
is turned on, and disabled when it's off. In the near future, several of
the internal configuration options will be added as public Angular
compiler options so that users can have fine-grained control over which
areas of the template type checker to enable, allowing for a more
incremental migration strategy.
PR Close#33066
For v9 we want the migration to the new i18n to be as
simple as possible.
Previously the developer had to positively choose to use
legacy messsage id support in the case that their translation
files had not been migrated to the new format by setting the
`legacyMessageIdFormat` option in tsconfig.json to the format
of their translation files.
Now this setting has been changed to `enableI18nLegacyMessageFormat`
as is a boolean that defaults to `true`. The format is then read from
the `i18nInFormat` option, which was previously used to trigger translations
in the pre-ivy angular compiler.
PR Close#33053
The `$localize` library uses a new message digest function for
computing message ids. This means that translations in legacy
translation files will no longer match the message ids in the code
and so will not be translated.
This commit adds the ability to specify the format of your legacy
translation files, so that the appropriate message id can be rendered
in the `$localize` tagged strings. This results in larger code size
and requires that all translations are in the legacy format.
Going forward the developer should migrate their translation files
to use the new message id format.
PR Close#32937
In ngc is was valid to set the "flatModuleOutFile" option to "null". This is sometimes
necessary if a tsconfig extends from another one but the "fatModuleOutFile" option
needs to be unset (note that "undefined" does not exist as value in JSON)
Now if ngtsc is used to compile the project, ngtsc will fail with an error because it
tries to do string manipulation on the "flatModuleOutFile". This happens because
ngtsc only skips flat module indices if the option is set to "undefined".
Since this is not compatible with what was supported in ngc and such exceptions
should be avoided, the flat module check is now aligned with ngc.
```
TypeError: Cannot read property 'replace' of null
at Object.normalizeSeparators (/home/circleci/project/node_modules/@angular/compiler-cli/src/ngtsc/util/src/path.js:35:21)
at new NgtscProgram (/home/circleci/project/node_modules/@angular/compiler-cli/src/ngtsc/program.js:126:52)
```
Additionally setting the `flatModuleOutFile` option to an empty string
currently results in unexpected behavior. No errors is thrown, but the
flat module index file will be `.ts` (no file name; just extension).
This is now also fixed by treating an empty string similarly to
`null`.
PR Close#32235
Previously, ngtsc attempted to use the .d.ts schema for HTML elements to
check bindings to DOM properties. However, the TypeScript lib.dom.d.ts
schema does not perfectly align with the Angular DomElementSchemaRegistry,
and these inconsistencies would cause issues in apps. There is also the
concern of supporting both CUSTOM_ELEMENTS_SCHEMA and NO_ERRORS_SCHEMA which
would have been very difficult to do in the existing system.
With this commit, the DomElementSchemaRegistry is employed in ngtsc to check
bindings to the DOM. Previous work on producing template diagnostics is used
to support generation of this different kind of error with the same high
quality of error message.
PR Close#32171
Historically, the Angular Compiler has produced both native TypeScript
diagnostics (called ts.Diagnostics) and its own internal Diagnostic format
(called an api.Diagnostic). This was done because TypeScript ts.Diagnostics
cannot be produced for files not in the ts.Program, and template type-
checking diagnostics are naturally produced for external .html template
files.
This design isn't optimal for several reasons:
1) Downstream tooling (such as the CLI) must support multiple formats of
diagnostics, adding to the maintenance burden.
2) ts.Diagnostics have gotten a lot better in recent releases, with support
for suggested changes, highlighting of the code in question, etc. None of
these changes have been of any benefit for api.Diagnostics, which have
continued to be reported in a very primitive fashion.
3) A future plugin model will not support anything but ts.Diagnostics, so
generating api.Diagnostics is a blocker for ngtsc-as-a-plugin.
4) The split complicates both the typings and the testing of ngtsc.
To fix this issue, this commit changes template type-checking to produce
ts.Diagnostics instead. Instead of reporting a special kind of diagnostic
for external template files, errors in a template are always reported in
a ts.Diagnostic that highlights the portion of the template which contains
the error. When this template text is distinct from the source .ts file
(for example, when the template is parsed from an external resource file),
additional contextual information links the error back to the originating
component.
A template error can thus be reported in 3 separate ways, depending on how
the template was configured:
1) For inline template strings which can be directly mapped to offsets in
the TS code, ts.Diagnostics point to real ranges in the source.
This is the case if an inline template is used with a string literal or a
"no-substitution" string. For example:
```typescript
@Component({..., template: `
<p>Bar: {{baz}}</p>
`})
export class TestCmp {
bar: string;
}
```
The above template contains an error (no 'baz' property of `TestCmp`). The
error produced by TS will look like:
```
<p>Bar: {{baz}}</p>
~~~
test.ts:2:11 - error TS2339: Property 'baz' does not exist on type 'TestCmp'. Did you mean 'bar'?
```
2) For template strings which cannot be directly mapped to offsets in the
TS code, a logical offset into the template string will be included in
the error message. For example:
```typescript
const SOME_TEMPLATE = '<p>Bar: {{baz}}</p>';
@Component({..., template: SOME_TEMPLATE})
export class TestCmp {
bar: string;
}
```
Because the template is a reference to another variable and is not an
inline string constant, the compiler will not be able to use "absolute"
positions when parsing the template. As a result, errors will report logical
offsets into the template string:
```
<p>Bar: {{baz}}</p>
~~~
test.ts (TestCmp template):2:15 - error TS2339: Property 'baz' does not exist on type 'TestCmp'.
test.ts:3:28
@Component({..., template: TEMPLATE})
~~~~~~~~
Error occurs in the template of component TestCmp.
```
This error message uses logical offsets into the template string, and also
gives a reference to the `TEMPLATE` expression from which the template was
parsed. This helps in locating the component which contains the error.
3) For external templates (templateUrl), the error message is delivered
within the HTML template file (testcmp.html) instead, and additional
information contextualizes the error on the templateUrl expression from
which the template file was determined:
```
<p>Bar: {{baz}}</p>
~~~
testcmp.html:2:15 - error TS2339: Property 'baz' does not exist on type 'TestCmp'.
test.ts:10:31
@Component({..., templateUrl: './testcmp.html'})
~~~~~~~~~~~~~~~~
Error occurs in the template of component TestCmp.
```
PR Close#31952
Previously if only a component template changed then we would know to
rebuild its component source file. But the compilation was incorrect if the
component was part of an NgModule, since we were not capturing the
compilation scope information that had a been acquired from the NgModule
and was not being regenerated since we were not needing to recompile
the NgModule.
Now we register compilation scope information for each component, via the
`ComponentScopeRegistry` interface, so that it is available for incremental
compilation.
The `ComponentDecoratorHandler` now reads the compilation scope from a
`ComponentScopeReader` interface which is implemented as a compound
reader composed of the original `LocalModuleScopeRegistry` and the
`IncrementalState`.
Fixes#31654
PR Close#31932
