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
The function `makeTemplateDiagnostic` was accepting an error code of type
`number`, making it easy to accidentally pass an `ErrorCode` directly and
not convert it to an Angular diagnostic code first.
This commit refactors `makeTemplateDiagnostic` to accept `ErrorCode` up
front, and convert it internally. This is less error-prone.
PR Close#34460
Previously, ngtsc would perform scope analysis (which directives/pipes are
available inside a component's template) and template type-checking of that
template as separate steps. If a component's scope was somehow invalid (e.g.
its NgModule imported something which wasn't another NgModule), the
component was treated as not having a scope. This meant that during template
type-checking, errors would be produced for any invalid expressions/usage of
other components that should have been in the scope.
This commit changes ngtsc to skip template type-checking of a component if
its scope is erroneous (as opposed to not present in the first place). Thus,
users aren't overwhelmed with diagnostic errors for the template and are
only informed of the root cause of the problem: an invalid NgModule scope.
Fixes#33849
PR Close#34460
Previously each NgModule trait checked its own scope for valid declarations
during 'resolve'. This worked, but caused the LocalModuleScopeRegistry to
declare that NgModule scopes were valid even if they contained invalid
declarations.
This commit moves the generation of diagnostic errors to the
LocalModuleScopeRegistry where it belongs. Now the registry can consider an
NgModule's scope to be invalid if it contains invalid declarations.
PR Close#34460
The template type checker generates TypeScript expressions for any
expression that occurs in a template, so that TypeScript can check it
and produce errors. Some expressions as they occur in a template may be
translated into TypeScript code multiple times, for instance a binding
to a directive input that has a template guard.
One example would be the `NgIf` directive, which has a template guard to
narrow the type in the template as appropriate. Given the following
template:
```typescript
@Component({
template: '<div *ngIf="person">{{ person.name }}</div>'
})
class AppComponent {
person?: { name: string };
}
```
A type check block (TCB) with roughly the following structure is
created:
```typescript
function tcb(ctx: AppComponent) {
const t1 = NgIf.ngTypeCtor({ ngIf: ctx.person });
if (ctx.person) {
"" + ctx.person.name;
}
}
```
Notice how the `*ngIf="person"` binding is present twice: once in the
type constructor call and once in the `if` guard. As such, TypeScript
will check both instances and would produce duplicate errors, if any
were found.
Another instance is when the safe navigation operator is used, where an
expression such as `person?.name` is emitted into the TCB as
`person != null ? person!.name : undefined`. As can be seen, the
left-hand side expression `person` occurs twice in the TCB.
This commit adds the ability to insert markers into the TCB that
indicate that any errors within the expression should be ignored. This
is similar to `@ts-ignore`, however it can be applied more granularly.
PR Close#34417
Previously, the type checker would compute an absolute source span by
combining an expression AST node's `ParseSpan` (relative to the start of
the expression) together with the absolute offset of the expression as
represented in a `ParseSourceSpan`, to arrive at a span relative to the
start of the file. This information is now directly available on an
expression AST node in the `AST.sourceSpan` property, which can be used
instead.
PR Close#34417
Now that the source to typings matching is able to handle
aliasing of exports, there is no need to handle aliases in private
declarations analysis.
These were originally added to cope when the typings files had
to use the name that the original source files used when exporting.
PR Close#34254
Previously the identifiers used in the typings files were the same as
those used in the source files.
When the typings files and the source files do not match exactly, e.g.
when one of them is flattened, while the other is a deep tree, it is
possible for identifiers to be renamed.
This commit ensures that the correct identifier is used in typings files
when the typings file does not export the same name as the source file.
Fixes https://github.com/angular/ngcc-validation/pull/608
PR Close#34254
The naïve matching algorithm we previously used to match declarations in
source files to declarations in typings files was based only on the name
of the thing being declared. This did not handle cases where the declared
item had been exported via an alias - a common scenario when one of the two
file sets (source or typings) has been flattened, while the other has not.
The new algorithm tries to overcome this by creating two maps of export
name to declaration (i.e. `Map<string, ts.Declaration>`).
One for the source files and one for the typings files.
It then joins these two together by matching export names, resulting in a
new map that maps source declarations to typings declarations directly
(i.e. `Map<ts.Declaration, ts.Declaration>`).
This new map can handle the declaration names being different between the
source and typings as long as they are ultimately both exported with the
same alias name.
Further more, there is one map for "public exports", i.e. exported via the
root of the source tree (the entry-point), and another map for "private
exports", which are exported from individual files in the source tree but
not necessarily from the root. This second map can be used to "guess"
the mapping between exports in a deep (non-flat) file tree, which can be
used by ngcc to add required private exports to the entry-point.
Fixes#33593
PR Close#34254
In TS we can re-export imports using statements of the form:
```
export * from 'some-import';
```
This is downleveled in UMD to:
```
function factory(exports, someImport) {
function __export(m) {
for (var p in m) if (!exports.hasOwnProperty(p)) exports[p] = m[p];
}
__export(someImport);
}
```
This commit adds support for this.
PR Close#34254
In TS we can re-export imports using statements of the form:
```
export * from 'some-import';
```
This can be downleveled in CommonJS to either:
```
__export(require('some-import'));
```
or
```
var someImport = require('some-import');
__export(someImport);
```
Previously we only supported the first downleveled version.
This commit adds support for the second version.
PR Close#34254
Previously individual properties of the src bundle program were
passed to the reflection host constructors. But going forward,
more properties will be required. To prevent the signature getting
continually larger and more unwieldy, this change just passes the
whole src bundle to the constructor, allowing it to extract what it
needs.
PR Close#34254
This is not expected to have any noticeable perf impact, but it wasteful
nonetheless (and annoying when stepping through the code while debugging
`ngtsc`/`ngcc`).
PR Close#34441
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
A quirk of the Angular template parser is that when parsing templates in the
"default" mode, with options specified by the user, the source mapping
information in the template AST may be inaccurate. As a result, the compiler
parses the template twice: once for "emit" and once to produce an AST with
accurate sourcemaps for diagnostic production.
Previously, only the first parse was performed during analysis. The second
parse occurred during the template type-checking phase, just in time to
produce the template type-checking file.
However, with the reuse of analysis results during incremental builds, it
makes more sense to do the diagnostic parse eagerly during analysis so that
the work isn't unnecessarily repeated in subsequent builds. This commit
refactors the `ComponentDecoratorHandler` to do both parses eagerly, which
actually cleans up some complexity around template parsing as well.
PR Close#34334
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
The export scope of NgModules from external compilations units, as
present in .d.ts declarations, does not change during a compilation so
can be easily shared. There was already a cache but the computed export
scope was not actually stored there. This commit fixes that.
PR Close#34332
In Ivy it's illegal for a template to write to a template variable. So the
template:
```html
<ng-template let-somevar>
<button (click)="somevar = 3">Set var to 3</button>
</ng-template>
```
is erroneous and previously would fail to compile with an assertion error
from the `TemplateDefinitionBuilder`. This error wasn't particularly user-
friendly, though, as it lacked the context of which template or where the
error occurred.
In this commit, a new check in template type-checking is added which detects
such erroneous writes and produces a true diagnostic with the appropriate
context information.
Closes#33674
PR Close#34339
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
Previously the UMD rendering formatter assumed that
there would already be import (and an export) arguments
to the UMD factory function.
This commit adds support for this corner case.
Fixes#34138
PR Close#34353
When statically evalulating UMD code it is possible to find
that we are looking for the declaration of an identifier that
actually came from a typings file (rather than a UMD file).
Previously, the UMD reflection host would always try to use
a UMD specific algorithm for finding identifier declarations,
but when the id is actually in a typings file this resulted in the
returned declaration being the containing file of the declaration
rather than the declaration itself.
Now the UMD reflection host will check to see if the file containing
the identifier is a typings file and use the appropriate stategy.
PR Close#34356
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
The metadata collector for View Engine compilations emits error symbols
for static class members that have not been initialized, which prevents
a library from building successfully when `strictMetadataEmit` is
enabled, which is recommended for libraries to avoid issues in library
consumers. This is troublesome for libraries that are adopting static
members for the Ivy template type checker: these members don't need a
value assignment as only their type is of importance, however this
causes metadata errors. As such, a library used to be required to
initialize the special static members to workaround this error,
undesirably introducing a code-size overhead in terms of emitted
JavaScript code.
This commit modifies the collector logic to specifically ignore
the special static members for Ivy's template type checker, preventing
any errors from being recorded during the metadata collection.
PR Close#34296
For Ivy's template type checker it is possible to let a directive
specify static members to allow a wider type for some input:
```typescript
export class MatSelect {
@Input() disabled: boolean;
static ngAcceptInputType_disabled: boolean | string;
}
```
This allows a binding to the `MatSelect.disabled` input to be of type
boolean or string, whereas the `disabled` property itself is only of
type boolean.
Up until now, any static `ngAcceptInputType_*` property was not
inherited for subclasses of a directive class. This is cumbersome, as
the directive's inputs are inherited, so any acceptance member should as
well. To resolve this limitation, this commit extends the flattening of
directive metadata to include the acceptance members.
Fixes#33830
Resolves FW-1759
PR Close#34296
The undecorated child migration creates a synthetic decorator, which
contained `"exportAs": ["exportName"]` as obtained from the metadata of
the parent class. This is a problem, as `exportAs` needs to specified
as a comma-separated string instead of an array. This commit fixes the
bug by transforming the array of export names back to a comma-separated
string.
PR Close#34014
When ngcc is analyzing synthetically inserted decorators from a
migration, it is typically not expected that any diagnostics are
produced. In the situation where a diagnostic is produced, however, the
diagnostic would not be reported at all. This commit ensures that
diagnostics in migrations are reported.
PR Close#34014
The compiler exports a `formatDiagnostics` function which consumers can use
to print both ts and ng diagnostics. However, this function was previously
using the "old" style TypeScript diagnostics, as opposed to the modern
diagnostic printer which uses terminal colors and prints additional context
information.
This commit updates `formatDiagnostics` to use the modern formatter, plus to
update Ivy's negative error codes to Angular 'NG' errors.
The Angular CLI needs a little more work to use this function for printing
TS diagnostics, but this commit alone should fix Bazel builds as ngc-wrapped
goes through `formatDiagnostics`.
PR Close#34234
Previously, ternary expressions were emitted as:
condExpr ? trueCase : falseCase
However, this causes problems when ternary operations are nested. In
particular, a template expression of the form:
a?.b ? c : d
would have compiled to:
a == null ? null : a.b ? c : d
The ternary operator is right-associative, so that expression is interpreted
as:
a == null ? null : (a.b ? c : d)
when in reality left-associativity is desired in this particular instance:
(a == null ? null : a.b) ? c : d
This commit adds a check in the expression translator to detect such
left-associative usages of ternaries and to enforce such associativity with
parentheses when necessary.
A test is also added for the template type-checking expression translator,
to ensure it correctly produces right-associative expressions for ternaries
in the user's template.
Fixes#34087
PR Close#34221
Previously the `rootDir` was set to the entry-point path but
this is incorrect if the source files are stored in a directory outside
the entry-point path. This is the case in the latest versions of the
Angular CDK.
Instead the `rootDir` should be the containing package path, which is
guaranteed to include all the source for the entry-point.
---
A symptom of this is an error when ngcc is trying to process the source of
an entry-point format after the entry-point's typings have already been
processed by a previous processing run.
During processing the `_toR3Reference()` function gets called which in turn
makes a call to `ReflectionHost.getDtsDeclaration()`. If the typings files
are also being processed this returns the node from the dts typings files.
But if we have already processed the typings files and are now processing
only an entry-point format without typings, the call to
`ReflectionHost.getDtsDeclaration()` returns `null`.
When this value is `null`, a JS `valueRef` is passed through as the DTS
`typeRef` to the `ReferenceEmitter`. In this case, the `ReferenceEmitter`
fails during `emit()` because no `ReferenceEmitStrategy` is able to provide
an emission:
1) The `LocalIdentifierStrategy` is not able help because in this case
`ImportMode` is `ForceNewImport`.
2) The `LogicalProjectStrategy` cannot find the JS file below the `rootDir`.
The second strategy failure is fixed by this PR.
Fixes https://github.com/angular/ngcc-validation/issues/495
PR Close#34212
Commit that updated i18n message ids rendering (e524322c43) also introduced a couple tests that relied on a previous version of `ngI18nClosureMode` flag format. The `ngI18nClosureMode` usage format was changed in the followup commit (c4ce24647b) and triggered a problem with the mentioned tests. This commit updates the tests to a new `ngI18nClosureMode` flag usage format.
PR Close#34224
If the `ngI18nClosureMode` global check actually makes it
through to the runtime, then checks for its existence should
be guarded to prevent `Reference undefined` errors in strict
mode.
(Normally, it is stripped out by dead code elimination during
build optimization.)
This comment ensures that generated template code guards
this global check.
PR Close#34211
This is a follow-up to #33997 where some new generic parameters were added without defaults which is technically a breaking change. These changes add the defaults.
PR Close#34206
Prior to this commit, if a template (for example, generated using structural directive such as *ngIf) contains `ngProjectAs` attribute, it was not included into attributes array in generated code and as a result, these templates were not matched at runtime during content projection. This commit adds the logic to append `ngProjectAs` values into corresponding element's attribute arrays, so content projection works as expected.
PR Close#34200
Fixes ngtsc incorrectly logging an unknown element diagnostic for HTML elements that are inside an SVG `foreignObject` with the `xhtml` namespace.
Fixes#34171.
PR Close#34178
By ensuring that legacy i18n message ids are rendered into the templates
of components for packages processed by ngcc, we ensure that these packages
can be used in an application that may provide translations in a legacy
format.
Fixes#34056
PR Close#34135
Placing this configuration in to the bundle avoids having to pass the
value around through lots of function calls, but also could enable
support for different behaviour per bundle in the future.
PR Close#34135
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
We should only generate the `providedIn` property in injectable
defs if it has a non-null value. `null` does not communicate
any information to the runtime that isn't communicated already
by the absence of the property.
This should give us some modest code size savings.
PR Close#34116
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
crisbeto
Alex Rickabaugh
JoostK
Pete Bacon Darwin
George Kalpakas
Andrew Kushnir
Kara Erickson