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
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
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
In ESM5 decorated classes can be indicated by calls to `__decorate()`.
Previously the `ReflectionHost.findDecoratedClasses()` call would identify
helper calls of the form:
```
SomeClass = tslib_1.__decorate(...);
```
But it was missing calls of the form:
```
SomeClass = SomeClass_1 = tslib_1.__decorate(...);
```
This form is common in `@NgModule()` decorations, where the class
being decorated is referenced inside the decorator or another
member.
This commit now ensures that a chain of assignments, of any length,
is now identified as a class decoration if it results in a call to
`__decorate()`.
Fixes#27841
PR Close#27848
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
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
Upcoming work to implement import resolution will change the dependencies
of some higher-level classes in ngtsc & ngcc. This necessitates changes in
how these classes are created and the lifecycle of the ts.Program in ngtsc
& ngcc.
To avoid complicating the implementation work with refactoring as a result
of the new dependencies, the refactoring is performed in this commit as a
separate prepatory step.
In ngtsc, the testing harness is modified to allow easier access to some
aspects of the ts.Program.
In ngcc, the main change is that the DecorationAnalyzer is created with the
ts.Program as a constructor parameter. This is not a lifecycle change, as
it was previously created with the ts.TypeChecker which is derived from the
ts.Program anyways. This change requires some reorganization in ngcc to
accommodate, especially in testing harnesses where DecorationAnalyzer is
created manually in a number of specs.
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
Exported functions or static method that return a `ModuleWithProviders`
compatible structure need to provide information about the referenced
`NgModule` type in their return type.
This allows ngtsc to be able to understand the type of `NgModule` that is
being returned from calls to the function, without having to dig into the
internals of the compiled library.
There are two ways to provide this information:
* Add a type parameter to the `ModuleWithProviders` return type. E.g.
```
static forRoot(): ModuleWithProviders<SomeNgModule>;
```
* Convert the return type to a union that includes a literal type. E.g.
```
static forRoot(): (SomeOtherType)&{ngModule:SomeNgModule};
```
This commit updates the rendering of typings files to include this type
information on all matching functions/methods.
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
A surprising interaction with the MagicString library caused inserted
Ivy definitions to be dropped during the removal of decorators, iff all
decorators on the class could be removed. In that case, the removal
location corresponds with the exact location where Ivy definitions were
inserted into.
This commit moves the removal of decorators to occur before Ivy
definitions are inserted. This effectively avoids the problem, as later
inserted text fragments will be retained by MagicString.
PR Close#27159
If a template contains specific TypeScript syntax, such as a non-null
assertion, the code that is emitted from ngcc into a JavaScript bundle
should not retain such syntax as it is invalid in JS.
A full-blown TypeScript emit of a complete ts.SourceFile would be
required to be able to emit JS and possibly downlevel into a lower
language target, which is not an option for ngcc as it currently
operates on partial ASTs, not full source files.
Instead, ngtsc no longer produces TypeScript specific syntax in the first
place, such that TypeScript print logic will only generate JS code.
PR Close#27051
Ngcc will now render additional exports for classes that are referenced in
`NgModule` decorated classes, but which were not publicly exported
from an entry-point of the package.
This is important because when ngtsc compiles libraries processed by ngcc
it needs to be able to publcly access decorated classes that are referenced
by `NgModule` decorated classes in order to build templates that use these
classes.
Doing this re-exporting is not without its risks. There are chances that
the class is not exported correctly: there may already be similarly named
exports from the entry-point or the class may be being aliased. But there
is not much more we can do from the point of view of ngcc to workaround
such scenarios. Generally, packages should have been built so that this
approach works.
PR Close#26906
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
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
If a decorated class is not publicly exported via an entry-point then the
previous approach to finding the associated typings file failed.
Now we ensure that we extract all the class declarations from the
dtsTypings program, even if they are not exported from the entry-point.
This is achieved by also parsing statements of each source file, rather
than just parsing classes that are exported from the entry-point.
Because we now look at all the files, it is possible for there to be multiple
class declarations with the same local name. In this case, only the first
declaration with a given name is added to the map; subsequent classes are
ignored.
We are most interested in classes that are publicly exported from the
entry-point, so these are added to the map first, to ensure that they are
not ignored.
PR Close#26906
When ngtsc compiles @angular/core, it rewrites core imports to the
r3_symbols.ts file that exposes all internal symbols under their
external name. When creating the FESM bundle, the r3_symbols.ts file
causes the external symbol names to be rewritten to their internal name.
Under ngcc compilations of FESM bundles, the indirection of
r3_symbols.ts is no longer in place such that the external names are
retained in the bundle. Previously, the external name `ɵdefineNgModule`
was explicitly declared internally to resolve this issue, but the
recently added `setClassMetadata` was not declared as such, causing
runtime errors.
Instead of relying on the r3_symbols.ts file to perform the rewrite of
the external modules to their internal variants, the translation is
moved into the `ImportManager` during the compilation itself. This
avoids the need for providing the external name manually.
PR Close#27055
This fixes an issue where packages would be skipped if they contained
e.g. RxJS 5 style imports such as
```
import { observeOn } from 'rxjs/operators/observeOn';
```
Given that no package.json file can be found at the imported path, the
dependency would be reported missing, causing the package to be skipped.
PR Close#27031
Previously the ivy definition calls we going directly after the
class constructor function But this meant that the lifecycle
hooks attached to the prototype were ignored by the ngtsc
compiler.
Now the definitions are written to the end of the IIFE block,
just before the return statement.
Closes#26849
PR Close#26856
For each package entry-point there is only one format that
is used to compile the typings files (.d.ts). This will be
either esm2015 or fesm2015 (preferred). So we would not run
any dts processing in the renderer if we are not compiling
the appropriate format.
PR Close#26403
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
The rendering of typings is not specific to the package
format, so it doesn't make sense to put it in a specific
renderer.
As a result there is no real difference between esm5 and esm2015
renderers, so there is no point in having separate classes.
PR Close#26403
Previously we always used the non-flat format because we thought
that this was the one that would always be available.
It turns out that this is not the case and that only one of the flat and
non-flat formats may be available.
Therefore we should use whichever is available, defaulting to the flat
format if that exists, since that will be faster to parse.
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 Material project uses slightly different properties to the
core Angular project for specifying the different format entry-point.
This commit ensures that we map these properties correctly for both
types of project.
PR Close#26403
This commit causes a call to setClassMetadata() to be emitted for every
type being compiled by ngtsc (every Angular type). With this metadata,
the TestBed should be able to recompile these classes when overriding
decorator information.
Testing strategy: Tests in the previous commit for
generateSetClassMetadataCall() verify that the metadata as generated is
correct. This commit enables the generation for each DecoratorHandler,
and a test is added to ngtsc_spec to verify all decorated types have
metadata generated for them.
PR Close#26860
We are close enough to blacklist a few test targets, rather than whitelist targets to run...
Because bazel rules can be composed of other rules that don't inherit tags automatically,
I had to explicitly mark all of our ts_library and ng_module targes with "ivy-local" and
"ivy-jit" tags so that we can create a query that excludes all fixme- tagged targets even
if those targets are composed of other targets that don't inherit this tag.
This is the updated overview of ivy related bazel tags:
- ivy-only: target that builds or runs only under ivy
- fixme-ivy-jit: target that doesn't yet build or run under ivy with --compile=jit
- fixme-ivy-local: target that doesn't yet build or run under ivy with --compile=local
- no-ivy-jit: target that is not intended to build or run under ivy with --compile=jit
- no-ivy-local: target that is not intended to build or run under ivy with --compile=local
PR Close#26471
Originally, the ivy_switch mechanism used Bazel genrules to conditionally
compile one TS file or another depending on whether ngc or ngtsc was the
selected compiler. This was done because we wanted to avoid importing
certain modules (and thus pulling them into the build) if Ivy was on or
off. This mechanism had a major drawback: ivy_switch became a bottleneck
in the import graph, as it both imports from many places in the codebase
and is imported by many modules in the codebase. This frequently resulted
in cyclic imports which caused issues both with TS and Closure compilation.
It turns out ngcc needs both code paths in the bundle to perform the switch
during its operation anyway, so import switching was later abandoned. This
means that there's no real reason why the ivy_switch mechanism needed to
operate at the Bazel level, and for the ivy_switch file to be a bottleneck.
This commit removes the Bazel-level ivy_switch mechanism, and introduces
an additional TypeScript transform in ngtsc (and the pass-through tsc
compiler used for testing JIT) to perform the same operation that ngcc
does, and flip the switch during ngtsc compilation. This allows the
ivy_switch file to be removed, and the individual switches to be located
directly next to their consumers in the codebase, greatly mitigating the
circular import issues and making the mechanism much easier to use.
As part of this commit, the tag for marking switched variables was changed
from __PRE_NGCC__ to __PRE_R3__, since it's no longer just ngcc which
flips these tags. Most variables were renamed from R3_* to SWITCH_* as well,
since they're referenced mostly in render2 code.
Test strategy: existing test coverage is more than sufficient - if this
didn't work correctly it would break the hello world and todo apps.
PR Close#26550
