This fixes an issue with commit b6f6b117. In this commit, default imports
processed in a type-to-value conversion were recorded as non-local imports
with a '*' name, and the ImportManager generated a new default import for
them. When transpiled to ES2015 modules, this resulted in the following
correct code:
import i3 from './module';
// somewhere in the file, a value reference of i3:
{type: i3}
However, when the AST with this synthetic import and reference was
transpiled to non-ES2015 modules (for example, to commonjs) an issue
appeared:
var module_1 = require('./module');
{type: i3}
TypeScript renames the imported identifier from i3 to module_1, but doesn't
substitute later references to i3. This is because the import and reference
are both synthetic, and never went through the TypeScript AST step of
"binding" which associates the reference to its import. This association is
important during emit when the identifiers might change.
Synthetic (transformer-added) imports will never be bound properly. The only
possible solution is to reuse the user's original import and the identifier
from it, which will be properly downleveled. The issue with this approach
(which prompted the fix in b6f6b117) is that if the import is only used in a
type position, TypeScript will mark it for deletion in the generated JS,
even though additional non-type usages are added in the transformer. This
again would leave a dangling import.
To work around this, it's necessary for the compiler to keep track of
identifiers that it emits which came from default imports, and tell TS not
to remove those imports during transpilation. A `DefaultImportTracker` class
is implemented to perform this tracking. It implements a
`DefaultImportRecorder` interface, which is used to record two significant
pieces of information:
* when a WrappedNodeExpr is generated which refers to a default imported
value, the ts.Identifier is associated to the ts.ImportDeclaration via
the recorder.
* when that WrappedNodeExpr is later emitted as part of the statement /
expression translators, the fact that the ts.Identifier was used is
also recorded.
Combined, this tracking gives the `DefaultImportTracker` enough information
to implement another TS transformer, which can recognize default imports
which were used in the output of the Ivy transform and can prevent them
from being elided. This is done by creating a new ts.ImportDeclaration for
the imports with the same ts.ImportClause. A test verifies that this works.
PR Close#29266
When processing a JavaScript program, TS may come across a symbol that has
been imported from a TypeScript typings file.
In this case the compiler may pass the ReflectionHost a `prototype` symbol
as an export of the class.
This pseudo-member symbol has no declarations, which previously caused the
code in `Esm5ReflectionHost.reflectMembers()` to crash.
Now we just quietly ignore such a symbol and leave `Esm2015ReflectionHost`
to deal with it.
(As it happens `Esm2015ReflectionHost` also quietly ignores this symbol).
PR Close#29158
ngtsc occasionally converts a type reference (such as the type of a
parameter in a constructor) to a value reference (argument to a
directiveInject call). TypeScript has a bad habit of sometimes removing
the import statement associated with this type reference, because it's a
type only import when it initially looks at the file.
A solution to this is to always add an import to refer to a type position
value that's imported, and not rely on the existing import.
PR Close#29111
ngcc's reflection host needs to be able to determine all members of a
class, which it does by using the `ts.Symbol` from TypeScript's
TypeChecker. Such Symbol however may represent multiple class members
in the case of accessors; an equally named getter/setter accessor pair
is combined into a single `ts.Symbol`.
This commit introduces logic to recognize such accessors in order for
both the getter and setter to be considered as class member, similar to
ngtsc's behavior when operating on original TypeScript code.
One difference wrt the TypeScript host is that ngcc cannot see to which
accessor originally had any decorators applied to them, as decorators
are applied to the property descriptor in general, not a specific accessor.
If an accessor has both a setter and getter, any decorators are only
attached to the setter member.
PR Close#28357
Prior to this change, accessor functions for getters and setters would
not be considered as class member, as their declaration is vastly
different from ES2015 syntax.
With this change, the ES5 reflection host has learned to recognize the
downleveled syntax for accessors, allowing for them to be considered as
class member once again.
Fixes#28226
PR Close#28357
A constructor function may have been "synthesized" by TypeScript during
JavaScript emit, in the case no user-defined constructor exists and e.g.
property initializers are used. Those initializers need to be emitted
into a constructor in JavaScript, so the TypeScript compiler generates a
synthetic constructor.
This commit adds identification of such constructors as ngcc needs to be
able to tell if a class did originally have a constructor in the
TypeScript source. When a class has a superclass, a synthesized
constructor must not be considered as a user-defined constructor as that
prevents a base factory call from being created by ngtsc, resulting in a
factory function that does not inject the dependencies of the superclass.
Hence, we identify a default synthesized super call in the constructor
body, according to the structure that TypeScript emits.
PR Close#27897
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
There are a number of variables that need to be passed around
the program, in particular to the renderers, which benefit from being
stored in well defined objects.
The new `EntryPointBundle` structure is a specific format of an entry-point
and contains the compiled `BundleProgram` objects for the source and typings,
if appropriate.
This change helps with future refactoring, where we may need to add new
properties to this object. It allows us to maintain more stable APIs between
the constituent parts of ngcc, rather than passing lots of primitive values
around throughout the program.
PR Close#26906
1) The `DecorationAnalyzer now analyzes all source files, rather than just
the entry-point files, which fixes#26183.
2) The `DecoratorAnalyzer` now runs all the `handler.analyze()` calls
across the whole entry-point *before* running `handler.compile()`. This
ensures that dependencies between the decorated classes *within* an
entry-point are known to the handlers when running the compile process.
3) The `Renderer` now does the transformation of the typings (.d.ts) files
which allows us to support packages that only have flat format
entry-points better, and is faster, since we won't parse `.d.ts` files twice.
PR Close#26403
Going forward we need to be able to do the same work on both
flat and non-flat module formats (such as computing arity and
transforming .d.ts files)
PR Close#26403
The most recent Angular distributions have begun to use __decorate instead of Class.decorators.
This prevents `ngcc` from recognizing the classes and then fails to perform the transform to
ivy format.
Example:
```
var ApplicationModule = /** @class */ (function () {
// Inject ApplicationRef to make it eager...
function ApplicationModule(appRef) {
}
ApplicationModule = __decorate([
NgModule({ providers: APPLICATION_MODULE_PROVIDERS }),
__metadata("design:paramtypes", [ApplicationRef])
], ApplicationModule);
return ApplicationModule;
}());
```
Now `ngcc` recognizes `__decorate([...])` declarations and performs its transform.
See FW-379
PR Close#26236