In the @Component decorator, the 'host' field is an object which represents
host bindings. The type of this field is complex, but is generally of the
form {[key: string]: string}. Several different kinds of bindings can be
specified, depending on the structure of the key.
For example:
```
@Component({
host: {'[prop]': 'someExpr'}
})
```
will bind an expression 'someExpr' to the property 'prop'. This is known to
be a property binding because of the square brackets in the binding key.
If the binding key is a plain string (no brackets or parentheses), then it
is known as an attribute binding. In this case, the right-hand side is not
interpreted as an expression, but is instead a constant string.
There is no actual requirement that at build time, these constant strings
are known to the compiler, but this was previously enforced as a side effect
of requiring the binding expressions for property and event bindings to be
statically known (as they need to be parsed). This commit breaks that
relationship and allows the attribute bindings to be dynamic. In the case
that they are dynamic, the references to the dynamic values are reflected
into the Ivy instructions for attribute bindings.
PR Close#29033
Angular supports using <style> and <link> tags inline in component
templates, but previously such tags were not implemented within the ngtsc
compiler. This commit introduces that support.
FW-1069 #resolve
PR Close#28997
In certain configurations (such as the g3 repository) which have lots of
small compilation units as well as strict dependency checking on generated
code, ngtsc's default strategy of directly importing directives/pipes into
components will not work. To handle these cases, an additional mode is
introduced, and is enabled when using the FileToModuleHost provided by such
compilation environments.
In this mode, when ngtsc encounters an NgModule which re-exports another
from a different file, it will re-export all the directives it contains at
the ES2015 level. The exports will have a predictable name based on the
FileToModuleHost. For example, if the host says that a directive Foo is
from the 'root/external/foo' module, ngtsc will add:
```
export {Foo as ɵng$root$external$foo$$Foo} from 'root/external/foo';
```
Consumers of the re-exported directive will then import it via this path
instead of directly from root/external/foo, preserving strict dependency
semantics.
PR Close#28852
This commit splits apart selector_scope.ts in ngtsc and extracts the logic
into two separate classes, the LocalModuleScopeRegistry and the
DtsModuleScopeResolver. The logic is cleaned up significantly and new tests
are added to verify behavior.
LocalModuleScopeRegistry implements the NgModule semantics for compilation
scopes, and handles NgModules declared in the current compilation unit.
DtsModuleScopeResolver implements simpler logic for export scopes and
handles NgModules declared in .d.ts files.
This is done in preparation for the addition of re-export logic to solve
StrictDeps issues.
PR Close#28852
This commit adds support for the `static: true` flag in
`ViewChild` queries. Prior to this commit, all `ViewChild`
queries were resolved after change detection ran. This is
a problem for backwards compatibility because View Engine
also supported "static" queries which would resolve before
change detection.
Now if users add a `static: true` option, the query will be
resolved in creation mode (before change detection runs).
For example:
```ts
@ViewChild(TemplateRef, {static: true}) template !: TemplateRef;
```
This feature will come in handy for components that need
to create components dynamically.
PR Close#28811
Previously, `ngtsc` detected class inheritance in a way that only worked
in TS or ES2015 code. As a result, inheritance would not be detected for
code in ES5 format, such as when running `ngtsc` through `ngcc` to
transform old-style Angular code to ivy format.
This commit fixes it by delegating class inheritance detection to the
current `ReflectionHost`, which is able to correctly interpret the used
code format.
PR Close#28773
Accounts for schemas in when validating properties in Ivy.
This PR resolves FW-819.
A couple of notes:
* I had to rework the test slightly, in order to have it fail when we expect it to. The one in master is passing since Ivy's validation runs during the update phase, rather than creation.
* I had to deviate from the design in FW-819 and not add an `enableSchema` instruction, because the schema is part of the `NgModule` scope, however the scope is only assigned to a component once all of the module's declarations have been resolved and some of them can be async. Instead, I opted to have the `schemas` on the component definition.
PR Close#28637
The ultimate goal of this commit is to make use of fileNameToModuleName to
get the module specifier to use when generating an import, when that API is
available in the CompilerHost that ngtsc is created with.
As part of getting there, the way in which ngtsc tracks references and
generates import module specifiers is refactored considerably. References
are tracked with the Reference class, and previously ngtsc had several
different kinds of Reference. An AbsoluteReference represented a declaration
which needed to be imported via an absolute module specifier tracked in the
AbsoluteReference, and a RelativeReference represented a declaration from
the local program, imported via relative path or referred to directly by
identifier if possible. Thus, how to refer to a particular declaration was
encoded into the Reference type _at the time of creation of the Reference_.
This commit refactors that logic and reduces Reference to a single class
with no subclasses. A Reference represents a node being referenced, plus
context about how the node was located. This context includes a
"bestGuessOwningModule", the compiler's best guess at which absolute
module specifier has defined this reference. For example, if the compiler
arrives at the declaration of CommonModule via an import to @angular/common,
then any references obtained from CommonModule (e.g. NgIf) will also be
considered to be owned by @angular/common.
A ReferenceEmitter class and accompanying ReferenceEmitStrategy interface
are introduced. To produce an Expression referring to a given Reference'd
node, the ReferenceEmitter consults a sequence of ReferenceEmitStrategy
implementations.
Several different strategies are defined:
- LocalIdentifierStrategy: use local ts.Identifiers if available.
- AbsoluteModuleStrategy: if the Reference has a bestGuessOwningModule,
import the node via an absolute import from that module specifier.
- LogicalProjectStrategy: if the Reference is in the logical project
(is under the project rootDirs), import the node via a relative import.
- FileToModuleStrategy: use a FileToModuleHost to generate the module
specifier by which to import the node.
Depending on the availability of fileNameToModuleName in the CompilerHost,
then, a different collection of these strategies is used for compilation.
PR Close#28523
Previously, ngtsc would throw an error if two decorators were matched on
the same class simultaneously. However, @Injectable is a special case, and
it appears frequently on component, directive, and pipe classes. For pipes
in particular, it's a common pattern to treat the pipe class also as an
injectable service.
ngtsc actually lacked the capability to compile multiple matching
decorators on a class, so this commit adds support for that. Decorator
handlers (and thus the decorators they match) are classified into three
categories: PRIMARY, SHARED, and WEAK.
PRIMARY handlers compile decorators that cannot coexist with other primary
decorators. The handlers for Component, Directive, Pipe, and NgModule are
marked as PRIMARY. A class may only have one decorator from this group.
SHARED handlers compile decorators that can coexist with others. Injectable
is the only decorator in this category, meaning it's valid to put an
@Injectable decorator on a previously decorated class.
WEAK handlers behave like SHARED, but are dropped if any non-WEAK handler
matches a class. The handler which compiles ngBaseDef is WEAK, since
ngBaseDef is only needed if a class doesn't otherwise have a decorator.
Tests are added to validate that @Injectable can coexist with the other
decorators and that an error is generated when mixing the primaries.
PR Close#28523
In the past, @Injectable had no side effects and existing Angular code is
therefore littered with @Injectable usage on classes which are not intended
to be injected.
A common example is:
@Injectable()
class Foo {
constructor(private notInjectable: string) {}
}
and somewhere else:
providers: [{provide: Foo, useFactory: ...})
Here, there is no need for Foo to be injectable - indeed, it's impossible
for the DI system to create an instance of it, as it has a non-injectable
constructor. The provider configures a factory for the DI system to be
able to create instances of Foo.
Adding @Injectable in Ivy signifies that the class's own constructor, and
not a provider, determines how the class will be created.
This commit adds logic to compile classes which are marked with @Injectable
but are otherwise not injectable, and create an ngInjectableDef field with
a factory function that throws an error. This way, existing code in the wild
continues to compile, but if someone attempts to use the injectable it will
fail with a useful error message.
In the case where strictInjectionParameters is set to true, a compile-time
error is thrown instead of the runtime error, as ngtsc has enough
information to determine when injection couldn't possibly be valid.
PR Close#28523
Some applications use enum values in their host bindings:
@Component({
host: {
'[prop]': EnumType.Key,
}, ...
})
This commit changes the resolution of host properties to follow the enum
declaration and extract the correct value for the binding.
PR Close#28523
During analysis, the `ComponentDecoratorHandler` passes the component
template to the `parseTemplate()` function. Previously, there was little or
no information about the original source file, where the template is found,
passed when calling this function.
Now, we correctly compute the URL of the source of the template, both
for external `templateUrl` and in-line `template` cases. Further in the
in-line template case we compute the character range of the template
in its containing source file; *but only in the case that the template is
a simple string literal*. If the template is actually a dynamic value like
an interpolated string or a function call, then we do not try to add the
originating source file information.
The translator that converts Ivy AST nodes to TypeScript now adds these
template specific source mappings, which account for the file where
the template was found, to the templates to support stepping through the
template creation and update code when debugging an Angular application.
Note that some versions of TypeScript have a bug which means they cannot
support external template source-maps. We check for this via the
`canSourceMapExternalTemplates()` helper function and avoid trying to
add template mappings to external templates if not supported.
PR Close#28055
In View Engine, we supported @Input and @ContentChild annotations
on the same property. This feature was somewhat brittle because
it would only work for static queries, so it would break if a
content child was passed in wrapped in an *ngIf. Due to the
inconsistent behavior and low usage both internally and externally,
we will likely be deprecating it in the next version, and it does
not make sense to perpetuate it in Ivy.
This commit ensures that we now throw in Ivy if we encounter the
two annotations on the same property.
PR Close#28415
Prior to this change we may encounter some errors (like pipes being used where they should not be used) while compiling Host Bindings and Listeners. With this update we move validation logic to the analyze phase and throw an error if something is wrong. This also aligns error messages between Ivy and VE.
PR Close#28356
In some cases, calling getSourceFile() on a node from within a TS
transform can return undefined (against the signature of the method).
In these cases, getting the original node first will work.
PR Close#28412
By its nature, Ivy alters the import graph of a TS program, adding imports
where template dependencies exist. For example, if ComponentA uses PipeB
in its template, Ivy will insert an import of PipeB into the file in which
ComponentA is declared.
Any insertion of an import into a program has the potential to introduce a
cycle into the import graph. If for some reason the file in which PipeB is
declared imports the file in which ComponentA is declared (maybe it makes
use of a service or utility function that happens to be in the same file as
ComponentA) then this could create an import cycle. This turns out to
happen quite regularly in larger Angular codebases.
TypeScript and the Ivy runtime have no issues with such cycles. However,
other tools are not so accepting. In particular the Closure Compiler is
very anti-cycle.
To mitigate this problem, it's necessary to detect when the insertion of
an import would create a cycle. ngtsc can then use a different strategy,
known as "remote scoping", instead of directly writing a reference from
one component to another. Under remote scoping, a function
'setComponentScope' is called after the declaration of the component's
module, which does not require the addition of new imports.
FW-647 #resolve
PR Close#28169
This commit uses the NgModuleRouteAnalyzer introduced previously to
implement listLazyRoutes() for NgtscProgram. Currently this implementation
is limited to listing routes globally and cannot list routes for a given lazy
module. Testing seems to indicate that the CLI uses the global form, but this
should be verified.
Jira issue: FW-629
PR Close#27697
Resources can be loaded in the context of another file, which
means that the path to the resource file must be resolved
before it can be loaded.
Previously the API of this interface did not allow the client
code to get access to the resolved URL which is used to load
the resource.
Now this API has been refactored so that you must do the
resource URL resolving first and the loading expects a
resolved URL.
PR Close#28199
This code was throwing if the `deps` array of a provider has several elements, but at the next line it resolves them... With this check `ngtsc` couldn’t compile `ng-bootstrap` for example.
PR Close#28076
Prior to this change Component decorator was resolving `encapsulation` value a bit incorrectly, which resulted in `encapsulation: NaN` in compiled code. Now we resolve the value as Enum memeber and throw if it's not the case. As a part of this update, the `changeDetection` field handling is also added, the resolution logic is the same as the one used for `encapsulation` field.
PR Close#27971
exportAs in @Directive metadata supports multiple values, separated by
commas. Previously it was treated as a single value string.
This commit modifies the compiler to understand that exportAs is a
string[]. It stops short of carrying the multiple values through to the
runtime. Instead, it only emits the first one. A future commit will modify
the runtime to accept all the values.
PR Close#28001
Currently the ImportManager class handles various rewriting actions of
imports when compiling @angular/core. This is required as code compiled
within @angular/core cannot import from '@angular/core'. To work around
this, imports are rewritten to get core symbols from a particular file,
r3_symbols.ts.
In this refactoring, this rewriting logic is moved out of the ImportManager
and put behind an interface, ImportRewriter. There are three implementers
of the interface:
* NoopImportRewriter, used for compiling all non-core packages.
* R3SymbolsImportRewriter, used when ngtsc compiles @angular/core.
* NgccFlatImportRewriter, used when ngcc compiles @angular/core (special
logic is needed because ngcc has to rewrite imports in flat bundles
differently than in non-flat bundles).
This is a precursor to using this rewriting logic in other contexts besides
the ImportManager.
PR Close#27998
Previously, ngtsc would assume that a given directive/pipe being imported
from an external package was importable using the same name by which it
was declared. This isn't always true; sometimes a package will export a
directive under a different name. For example, Angular frequently prefixes
directive names with the 'ɵ' character to indicate that they're part of
the package's private API, and not for public consumption.
This commit introduces the TsReferenceResolver class which, given a
declaration to import and a module name to import it from, can determine
the exported name of the declared class within the module. This allows
ngtsc to pick the correct name by which to import the class instead of
making assumptions about how it was exported.
This resolver is used to select a correct symbol name when creating an
AbsoluteReference.
FW-517 #resolve
FW-536 #resolve
PR Close#27743
This commit adds tracking of modules, directives, and pipes which are made
visible to consumers through NgModules exported from the package entrypoint.
ngtsc will now produce a diagnostic if such classes are not themselves
exported via the entrypoint (as this is a requirement for downstream
consumers to use them with Ivy).
To accomplish this, a graph of references is created and populated via the
ReferencesRegistry. Symbols exported via the package entrypoint are compared
against the graph to determine if any publicly visible symbols are not
properly exported. Diagnostics are produced for each one which also show the
path by which they become visible.
This commit also introduces a diagnostic (instead of a hard compiler crash)
if an entrypoint file cannot be correctly determined.
PR Close#27743
This refactoring moves code around between a few of the ngtsc subpackages,
with the goal of having a more logical package structure. Additional
interfaces are also introduced where they make sense.
The 'metadata' package formerly contained both the partial evaluator,
the TypeScriptReflectionHost as well as some other reflection functions,
and the Reference interface and various implementations. This package
was split into 3 parts.
The partial evaluator now has its own package 'partial_evaluator', and
exists behind an interface PartialEvaluator instead of a top-level
function. In the future this will be useful for reducing churn as the
partial evaluator becomes more complicated.
The TypeScriptReflectionHost and other miscellaneous functions have moved
into a new 'reflection' package. The former 'host' package which contained
the ReflectionHost interface and associated types was also merged into this
new 'reflection' package.
Finally, the Reference APIs were moved to the 'imports' package, which will
consolidate all import-related logic in ngtsc.
PR Close#27743
Normally functions that return `ModuleWithProvider` objects should parameterize
the return type to include the type of `NgModule` that is being returned. For
example `forRoot(): ModuleWithProviders<RouterModule>`.
But in some cases, especially those generated by nccc, these functions to not
explicitly declare `ModuleWithProviders` as their return type. Instead they
return a "intersection" type, one of whose members is a type literal that
declares the `NgModule` type returned. For example:
`forRoot(): CustomType&{ngModule:RouterModule}`.
This commit changes the `NgModuleDecoratorHandler` so that it can extract
the `NgModule` type from either kind of declaration.
PR Close#27326
To support updating `ModuleWithProviders` calls,
we need to be able to map exported functions between
source and typings files, as well as classes.
PR Close#27326
ngcc would feed ngtsc with the function declaration inside of an IIFE as
that is considered the class symbol's declaration node, according to
TypeScript's `ts.Symbol.valueDeclaration`. ngtsc however only considered
variable decls and actual class decls as potential class declarations,
so given the function declaration node it would fail to generate the
`setClassMetadata` call.
ngtsc no longer makes its own assumptions about what classes look like,
but always asks the reflection host to yield this kind of information.
PR Close#27438
In Ivy, a pure call to `setClassMetadata` is inserted to retain the
information that would otherwise be lost while eliding the Angular
decorators. In the past, the Angular constructor decorators were
wrapped inside of an anonymous function which was only evaluated once
`ReflectionCapabilities` was requested for such metadata. This approach
prevents forward references from inside the constructor parameter
decorators from being evaluated before they are available.
In the `setClassMetadata` call, the constructor parameters were not wrapped
within an anonymous function, such that forward references were evaluated
too early, causing runtime errors.
This commit changes the `setClassMetadata` call to pass the constructor
parameter decorators inside of an anonymous function again, such that
forward references are not resolved until requested by
`ReflectionCapabilities`, therefore avoiding the early reads of forward refs.
PR Close#27561
With ngcc's ability to fixup pre-Ivy ModuleWithProviders such that they
include a reference to the NgModule type, the type may become a qualified
name:
```
import {ModuleWithProviders} from '@angular/core';
import * as ngcc0 from './module';
export declare provide(): ModuleWithProviders<ngcc0.Module>;
```
ngtsc now takes this situation into account when reflecting a
ModuleWithProvider's type argument.
PR Close#27562
Analogously to directives, the `ngInjectableDef` field in .d.ts files is
annotated with the type of service that it represents. If the service
contains required generic type arguments, these must be included in
the .d.ts file.
PR Close#27037
A previous fix to ngtsc opened the door for duplicate directives in
the 'directives' array of a component. This would happen if the directive
was declared in a module which was imported more than once within the
component's module.
This commit adds deduplication when the component's scope is materialized,
so declarations which arrive via more than one module import are coalesced.
PR Close#27462
Previously ngtsc assumed resource files (templateUrl, styleUrls) would be
physically present in the file system relative to the .ts file which
referenced them. However, ngc previously resolved such references in the
context of ts.CompilerOptions.rootDirs. Material depends on this
functionality in its build.
This commit introduces resolution of resources by leveraging the TypeScript
module resolver, ts.resolveModuleName(). This resolver is used in a way
which will never succeed, but on failure will return a list of locations
checked. This list is then filtered to obtain the correct potential
locations of the resource.
PR Close#27357
This commit adds support for resolution of styleUrls to ngtsc. Previously
this field was never read, and so components with styleUrls would appear
unstyled after compilation.
PR Close#27357
The `NgModuleDecoratorHandler` can now register all the references that
it finds in the `NgModule` metadata, such as `declarations`, `imports`,
`exports` etc.
This information can then be used by ngcc to work out if any of these
references are internal only and need to be manually exported from a
library's entry-point.
PR Close#26906
Previously the concept of multiple directives with the same selector was
not supported by ngtsc. This is due to the treatment of directives for a
component as a Map from selector to the directive, which is an erroneous
representation.
Now the directives for a component are stored as an array which supports
multiple directives with the same selector.
Testing strategy: a new ngtsc_spec test asserts that multiple directives
with the same selector are matched on an element.
PR Close#27298
