An enum declaration in TypeScript code will be emitted into JavaScript
as a regular variable declaration, with the enum members being declared
inside an IIFE. For ngcc to support interpreting such variable
declarations as enum declarations with its members, ngcc needs to
recognize the enum declaration emit structure and extract all member
from the statements in the IIFE.
This commit extends the `ConcreteDeclaration` structure in the
`ReflectionHost` abstraction to be able to capture the enum members
on a variable declaration, as a substitute for the original
`ts.EnumDeclaration` as it existed in TypeScript code. The static
interpreter has been extended to handle the extracted enum members
as it would have done for `ts.EnumDeclaration`.
Fixes#35584
Resolves FW-2069
PR Close#36550
When ngcc is compiling an entry-point, it uses a `ReflectionHost` that
is specific to its format, e.g. ES2015, ES5, UMD or CommonJS. During the
compilation of that entry-point however, the reflector may be used to
reflect into external libraries using their declaration files.
Up until now this was achieved by letting all `ReflectionHost` classes
consider their parent class for reflector queries, thereby ending up in
the `TypeScriptReflectionHost` that is a common base class for all
reflector hosts. This approach has proven to be prone to bugs, as
failing to call into the base class would cause incompatibilities with
reading from declaration files.
The observation can be made that there's only two distinct kinds of
reflection host queries:
1. the reflector query is about code that is part of the entry-point
that is being compiled, or
2. the reflector query is for an external library that the entry-point
depends on, in which case the information is reflected
from the declaration files.
The `ReflectionHost` that was chosen for the entry-point should serve
only reflector queries for the first case, whereas a regular
`TypeScriptReflectionHost` should be used for the second case. This
avoids the problem where a format-specific `ReflectionHost` fails to
handle the second case correctly, as it isn't even considered for such
reflector queries.
This commit introduces a `ReflectionHost` that delegates to the
`TypeScriptReflectionHost` for AST nodes within declaration files,
otherwise delegating to the format-specific `ReflectionHost`.
Fixes#35078
Resolves FW-1859
PR Close#36089
In ES5 code, TypeScript requires certain helpers (such as
`__spreadArrays()`) to be able to support ES2015+ features. These
helpers can be either imported from `tslib` (by setting the
`importHelpers` TS compiler option to `true`) or emitted inline (by
setting the `importHelpers` and `noEmitHelpers` TS compiler options to
`false`, which is the default value for both).
Ngtsc's `StaticInterpreter` (which is also used during ngcc processing)
is able to statically evaluate some of these helpers (currently
`__assign()`, `__spread()` and `__spreadArrays()`), as long as
`ReflectionHost#getDefinitionOfFunction()` correctly detects the
declaration of the helper. For this to happen, the left-hand side of the
corresponding call expression (i.e. `__spread(...)` or
`tslib.__spread(...)`) must be evaluated as a function declaration for
`getDefinitionOfFunction()` to be called with.
In the case of imported helpers, the `tslib.__someHelper` expression was
resolved to a function declaration of the form
`export declare function __someHelper(...args: any[][]): any[];`, which
allows `getDefinitionOfFunction()` to correctly map it to a TS helper.
In contrast, in the case of emitted helpers (and regardless of the
module format: `CommonJS`, `ESNext`, `UMD`, etc.)), the `__someHelper`
identifier was resolved to a variable declaration of the form
`var __someHelper = (this && this.__someHelper) || function () { ... }`,
which upon further evaluation was categorized as a `DynamicValue`
(prohibiting further evaluation by the `getDefinitionOfFunction()`).
As a result of the above, emitted TypeScript helpers were not evaluated
in ES5 code.
---
This commit changes the detection of TS helpers to leverage the existing
`KnownFn` feature (previously only used for built-in functions).
`Esm5ReflectionHost` is changed to always return `KnownDeclaration`s for
TS helpers, both imported (`getExportsOfModule()`) as well as emitted
(`getDeclarationOfIdentifier()`).
Similar changes are made to `CommonJsReflectionHost` and
`UmdReflectionHost`.
The `KnownDeclaration`s are then mapped to `KnownFn`s in
`StaticInterpreter`, allowing it to statically evaluate call expressions
involving any kind of TS helpers.
Jira issue: https://angular-team.atlassian.net/browse/FW-1689
PR Close#35191
Consider a library that uses a shared constant for host bindings. e.g.
```ts
export const BASE_BINDINGS= {
'[class.mat-themed]': '_isThemed',
}
----
@Directive({
host: {...BASE_BINDINGS, '(click)': '...'}
})
export class Dir1 {}
@Directive({
host: {...BASE_BINDINGS, '(click)': '...'}
})
export class Dir2 {}
```
Previously when these components were shipped as part of the
library to NPM, consumers were able to consume `Dir1` and `Dir2`.
No errors showed up.
Now with Ivy, when ngcc tries to process the library, an error
will be thrown. The error is stating that the host bindings should
be an object (which they obviously are). This happens because
TypeScript transforms the object spread to individual
`Object.assign` calls (for compatibility).
The partial evaluator used by the `@Directive` annotation handler
is unable to process this expression because there is no
integrated support for `Object.assign`. In View Engine, this was
not a problem because the `metadata.json` files from the library
were used to compute the host bindings.
Fixes#34659
PR Close#34661
Previously, in cases were values were expensive to compute and would be
used multiple times, a combination of a regular `Map` and a helper
function (`getOrDefault()`) was used to ensure values were only computed
once.
This commit uses a special `Map`-like structure to compute and memoize
such expensive values without the need to a helper function.
PR Close#34512
While different, CommonJS and UMD have a lot in common regarding the
their exports are constructed. Therefore, there was some code
duplication between `CommonJsReflectionHost` and `UmdReflectionHost`.
This commit extracts some of the common bits into a separate file as
helpers to allow reusing the code in both `ReflectionHost`s.
PR Close#34512
Previously, `UmdReflectionHost` would only recognize re-exports of the
form `__export(someIdentifier)` and not `__export(require('...'))`.
However, it is possible in some UMD variations to have the latter format
as well. See discussion in https://github.com/angular/angular/pull/34254/files#r359515373
This commit adds support for re-export of the form
`__export(require('...'))` in UMD.
PR Close#34512
This fix was part of a broader `ngtsc`/`ngcc` fix in 02bab8cf9 (see
there for details). In 02bab8cf9, the fix was only applied to
`CommonJsReflectionHost`, but it is equally applicable to
`UmdReflectionHost`. Later in #34254, the fix was partially ported to
`UmdReflectionHost` by fixing the `extractUmdReexports()` method.
This commit fully fixes `ngcc`'s handling of inline exports for code in
UMD format.
PR Close#34512
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
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
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
This PR updates Angular to compile with TypeScript 3.6 while retaining
compatibility with TS3.5. We achieve this by inserting several `as any`
casts for compatiblity around `ts.CompilerHost` APIs.
PR Close#32908
In ngcc's reflection host for UMD and CommonJS bundles, custom logic is
present to resolve import details of an identifier. However, this custom
logic is unable to resolve an import for an identifier inside of
declaration files, as such files use the regular ESM import syntax.
As a consequence of this limitation, ngtsc is unable to resolve
`ModuleWithProviders` imports that are declared in an external library.
In that situation, ngtsc determines the type of the actual `NgModule`
that is imported, by looking in the library's declaration files for the
generic type argument on `ModuleWithProviders`. In this process, ngtsc
resolves the import for the `ModuleWithProviders` identifier to verify
that it is indeed the `ModuleWithProviders` type from `@angular/core`.
So, when the UMD reflection host was in use this resolution would fail,
therefore no `NgModule` type could be detected.
This commit fixes the bug by using the regular import resolution logic
in addition to the custom resolution logic that is required for UMD
and CommonJS bundles.
Fixes#31791
PR Close#32619
To improve cross platform support, all file access (and path manipulation)
is now done through a well known interface (`FileSystem`).
For testing a number of `MockFileSystem` implementations are provided.
These provide an in-memory file-system which emulates operating systems
like OS/X, Unix and Windows.
The current file system is always available via the static method,
`FileSystem.getFileSystem()`. This is also used by a number of static
methods on `AbsoluteFsPath` and `PathSegment`, to avoid having to pass
`FileSystem` objects around all the time. The result of this is that one
must be careful to ensure that the file-system has been initialized before
using any of these static methods. To prevent this happening accidentally
the current file system always starts out as an instance of `InvalidFileSystem`,
which will throw an error if any of its methods are called.
You can set the current file-system by calling `FileSystem.setFileSystem()`.
During testing you can call the helper function `initMockFileSystem(os)`
which takes a string name of the OS to emulate, and will also monkey-patch
aspects of the TypeScript library to ensure that TS is also using the
current file-system.
Finally there is the `NgtscCompilerHost` to be used for any TypeScript
compilation, which uses a given file-system.
All tests that interact with the file-system should be tested against each
of the mock file-systems. A series of helpers have been provided to support
such tests:
* `runInEachFileSystem()` - wrap your tests in this helper to run all the
wrapped tests in each of the mock file-systems.
* `addTestFilesToFileSystem()` - use this to add files and their contents
to the mock file system for testing.
* `loadTestFilesFromDisk()` - use this to load a mirror image of files on
disk into the in-memory mock file-system.
* `loadFakeCore()` - use this to load a fake version of `@angular/core`
into the mock file-system.
All ngcc and ngtsc source and tests now use this virtual file-system setup.
PR Close#30921
