The new function does not try to restrict the kind of AST node that it
finds, leaving that to the caller. This will make it more resuable in the
UMD reflection host.
PR Close#38959
Similarly to the change we landed in the `@angular/core` reflection
capabilities, we need to make sure that ngcc can detect pass-through
delegate constructors for classes using downleveled ES2015 output.
More details can be found in the preceding commit, and in the issue
outlining the problem: #38453.
Fixes#38453.
PR Close#38463
In TS 3.9, ES2015 output can contain ES classes that are wrapped in an
IIFE. So now ES2015 class declarations can look like one of:
```
class OuterClass1 {}
```
```
let OuterClass = class InnerClass {};
```
```
var AliasClass;
let OuterClass = AliasClass = class InnerClass {};
```
```
let OuterClass = (() => class InnerClass {}};
```
```
var AliasClass;
let OuterClass = AliasClass = (() => class InnerClass {})();
```
```
let OuterClass = (() => {
let AdjacentClass = class InnerClass {};
// ... static properties or decorators attached to `AdjacentClass`
return AdjacentClass;
})();
```
```
var AliasClass;
let OuterClass = AliasClass = (() => {
let AdjacentClass = class InnerClass {};
// ... static properties or decorators attached to `AdjacentClass`
return AdjacentClass;
})();
```
The `Esm5ReflectionHost` already handles slightly different IIFE wrappers
around function-based classes. This can be substantially reused when
fixing `Esm2015ReflectionHost`, since there is a lot of commonality
between the two.
This commit moves code from the `Esm5ReflectionHost` into the `Esm2015ReflectionHost`
and looks to share as much as possible between the two hosts.
PR Close#36989
The previous implementations of `hasBaseClass()` are almost
identical to the implementation of `getBaseClassExpression()`.
There is little benefit in duplicating this code so this refactoring
changes `hasBaseClass()` to just call `getBaseClassExpression()`.
This allows the various hosts that implement this to be simplified.
PR Close#36989
A number of overloads were added to `detectKnownDeclaration()` to
allow it to support `null` being passed through. In practice this could
easily be avoided, which allows the overloads to be removed and the
method signature and implementations to be simplified.
PR Close#36989
In TS 3.9 the compiler will start to wrap ES2015 classes in an IIFE to help with
tree-shaking when the class has "associated" statements.
E.g.
```ts
let PlatformLocation = /** @class */ (() => {
...
class PlatformLocation {
}
...
return PlatformLocation;
})();
```
This commit updates `Esm2015ReflectionHost` to support this format.
PR Close#36884
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 TypeScript downlevels ES2015+ code to ES5, it uses some helper
functions to emulate some ES2015+ features, such as spread syntax. The
TypeScript compiler can be configured to emit these helpers into the
transpiled code (which is controlled by the `noEmitHelpers` option -
false by default). It can also be configured to import these helpers
from the `tslib` module (which is controlled by the `importHelpers`
option - false by default).
While most of the time the helpers will be either emitted or imported,
it is possible that one configures their app to neither emit nor import
them. In that case, the helpers could, for example, be made available on
the global object. This is what `@nativescript/angular`
v9.0.0-next-2019-11-12-155500-01 does. See, for example, [common.js][1].
Ngcc must be able to detect and statically evaluate these helpers.
Previously, it was only able to detect emitted or imported helpers.
This commit adds support for detecting these helpers if they are neither
emitted nor imported. It does this by checking identifiers for which no
declaration (either concrete or inline) can be found against a list of
known TypeScript helper function names.
[1]: https://unpkg.com/browse/@nativescript/angular@9.0.0-next-2019-11-12-155500-01/common.js
PR Close#36418
The `NgccReflectionHost`s have logic for detecting certain known
declarations (such as `Object.assign()` and TypeScript helpers), which
allows the `PartialEvaluator` to evaluate expressions it would not be
able to statically evaluate otherwise.
This commit moves the logic for identifying these known declarations to
dedicated methods. This is in preparation of allowing ngcc's
`DelegatingReflectionHost` (introduced in #36089) to also apply the
known declaration detection logic when reflecting on TypeScript sources.
PR Close#36284
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
In ES5 and ES2015, class identifiers may have aliases. Previously, the
`NgccReflectionHost`s recognized the following formats:
- ES5:
```js
var MyClass = (function () {
function InnerClass() {}
InnerClass_1 = InnerClass;
...
}());
```
- ES2015:
```js
let MyClass = MyClass_1 = class MyClass { ... };
```
In addition to the above, this commit adds support for recognizing an
alias outside the IIFE in ES5 classes (which was previously not
supported):
```js
var MyClass = MyClass_1 = (function () { ... }());
```
Jira issue: [FW-1869](https://angular-team.atlassian.net/browse/FW-1869)
Partially addresses #35399.
PR Close#35527
`Esm5ReflectionHost#getInnerFunctionDeclarationFromClassDeclaration()`
was already called with `ts.Declaration`, not `ts.Node`, so we can
tighten its parameter type and get rid of a redundant check.
`getIifeBody()` (called inside
`getInnerFunctionDeclarationFromClassDeclaration()`) will check whether
the given `ts.Declaration` is a `ts.VariableDeclaration`.
PR Close#35527
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
The reflection hosts have been updated to support the following
code forms, which were found in some minified library code:
* The class IIFE not being wrapped in parentheses.
* Calls to `__decorate()` being combined with the IIFE return statement.
PR Close#33777
Previously the renderers were fixed so that they inserted extra
"adjacent" statements after the last static property of classes.
In order to help the build-optimizer (in Angular CLI) to be able to
tree-shake classes effectively, these statements should also appear
after any helper calls, such as `__decorate()`.
This commit moves the computation of this positioning into the
`NgccReflectionHost` via the `getEndOfClass()` method, which
returns the last statement that is related to the class.
FW-1668
PR Close#33689
We already have special cases for the `__spread` helper function and with this change we handle the new tslib helper introduced in version 1.10 `__spreadArrays`.
For more context see: https://github.com/microsoft/tslib/releases/tag/1.10.0Fixes: #33614
PR Close#33617
In ES5 the class consists of an outer variable declaration that is
initialised by an IIFE. Inside the IIFE the class is implemented by
an inner function declaration that is returned from the IIFE.
This inner declaration may have a different name to the outer
declaration.
This commit overrides `getInternalNameOfClass()` and
`getAdjacentNameOfClass()` in `Esm5ReflectionHost` with methods that
can find the correct inner declaration name identifier.
PR Close#33533
In ES5 modules, the class declarations consist of an IIFE with inner
and outer declarations that represent the class. The `EsmReflectionHost`
has logic to ensure that `getDeclarationOfIdentifier()` always returns the
outer declaration.
Before this commit, if an identifier referred to an alias of the inner
declaration, then `getDeclarationOfIdentifier()` was failing to find
the outer declaration - instead returning the inner declaration.
Now the identifier is correctly resolved up to the outer declaration
as expected.
This should fix some of the failing 3rd party packages discussed in
https://github.com/angular/ngcc-validation/issues/57.
PR Close#33252
In ngcc's reflection hosts for compiled JS bundles, such as ESM2015,
special care needs to be taken for classes as there may be an outer
declaration (referred to as "declaration") and an inner declaration
(referred to as "implementation") for a given class. Therefore, there
will also be two `ts.Symbol`s bound per class, and ngcc needs to switch
between those declarations and symbols depending on where certain
information can be found.
Prior to this commit, the `NgccReflectionHost` interface had methods
`getClassSymbol` and `findClassSymbols` that would return a `ts.Symbol`.
These class symbols would be used to kick off compilation of components
using ngtsc, so it is important for these symbols to correspond with the
publicly visible outer declaration of the class. However, the ESM2015
reflection host used to return the `ts.Symbol` for the inner
declaration, if the class was declared as follows:
```javascript
var MyClass = class MyClass {};
```
For the above code, `Esm2015ReflectionHost.getClassSymbol` would return
the `ts.Symbol` corresponding with the `class MyClass {}` declaration,
whereas it should have corresponded with the `var MyClass` declaration.
As a consequence, no `NgModule` could be resolved for the component, so
no components/directives would be in scope for the component. This
resulted in errors during runtime.
This commit resolves the issue by introducing a `NgccClassSymbol` that
contains references to both the outer and inner `ts.Symbol`, instead of
just a single `ts.Symbol`. This avoids the unclarity of whether a
`ts.Symbol` corresponds with the outer or inner declaration.
More details can be found here: https://hackmd.io/7nkgWOFWQlSRAuIW_8KPPwFixes#32078
Closes FW-1507
PR Close#32539
One of the compiler's tasks is to enumerate the exports of a given ES
module. This can happen for example to resolve `foo.bar` where `foo` is a
namespace import:
```typescript
import * as foo from './foo';
@NgModule({
directives: [foo.DIRECTIVES],
})
```
In this case, the compiler must enumerate the exports of `foo.ts` in order
to evaluate the expression `foo.DIRECTIVES`.
When this operation occurs under ngcc, it must deal with the different
module formats and types of exports that occur. In commonjs code, a problem
arises when certain exports are downleveled.
```typescript
export const DIRECTIVES = [
FooDir,
BarDir,
];
```
can be downleveled to:
```javascript
exports.DIRECTIVES = [
FooDir,
BarDir,
```
Previously, ngtsc and ngcc expected that any export would have an associated
`ts.Declaration` node. `export class`, `export function`, etc. all retain
`ts.Declaration`s even when downleveled. But the `export const` construct
above does not. Therefore, ngcc would not detect `DIRECTIVES` as an export
of `foo.ts`, and the evaluation of `foo.DIRECTIVES` would therefore fail.
To solve this problem, the core concept of an exported `Declaration`
according to the `ReflectionHost` API is split into a `ConcreteDeclaration`
which has a `ts.Declaration`, and an `InlineDeclaration` which instead has
a `ts.Expression`. Differentiating between these allows ngcc to return an
`InlineDeclaration` for `DIRECTIVES` and correctly keep track of this
export.
PR Close#32129
An identifier may become repeated when bundling multiple source files
into a single bundle, so bundlers have a strategy of suffixing non-unique
identifiers with a suffix like $2. Since ngcc operates on such bundles,
it needs to process potentially suffixed identifiers in their canonical
form without the suffix. The "ngx-pagination" package was previously not
compiled fully, as most decorators were not recognized.
This commit ensures that identifiers are first canonicalized by removing
the suffix, such that they are properly recognized and processed by ngcc.
Fixes#31540
PR Close#31614
Previously we expected the constructor parameter `decorators`
property to be an array wrapped in a function. Now we also support
an array not wrapped in a function.
PR Close#30591
Packages that have been compiled using an older version of TypeScript
can have their decorators at the top-level of the ES5 bundles, instead
of inside the IIFE that is emitted for the class. Before this change,
ngcc only took static property assignments inside the IIFE into account,
therefore missing the decorators that were assigned at the top-level.
This commit extends the ES5 host to look for static properties in two
places. Testcases for all bundle formats that contain ES5 have been added
to ensure that this works in the various flavours.
A patch is included to support UMD bundles. The UMD factory affects how
TypeScripts binds the static properties to symbols, see the docblock of
the patch function for more details.
PR Close#30795
Currently undecorated classes are intentionally not processed
with ngcc. This is causing unexpected behavior because decorator
handlers such as `base_def.ts` are specifically interested in class
definitions without top-level decorators, so that the base definition
can be generated if there are Angular-specific class members.
In order to ensure that undecorated base-classes work as expected
with Ivy, we need to run the decorator handlers for all top-level
class declarations (not only for those with decorators). This is similar
to when `ngtsc` runs decorator handlers when analyzing source-files.
Resolves FW-1355. Fixes https://github.com/angular/components/issues/16178
PR Close#30821
The usage of array spread syntax in source code may be downleveled to a
call to TypeScript's `__spread` helper function from `tslib`, depending
on the options `downlevelIteration` and `emitHelpers`. This proves
problematic for ngcc when it is processing ES5 formats, as the static
evaluator won't be able to interpret those calls.
A custom foreign function resolver is not sufficient in this case, as
`tslib` may be emitted into the library code itself. In that case, a
helper function can be resolved to an actual function with body, such
that it won't be considered as foreign function. Instead, a reflection
host can now indicate that the definition of a function corresponds with
a certain TypeScript helper, such that it becomes statically evaluable
in ngtsc.
Resolves#30299
PR Close#30492
Previously we were relying upon the `.get()` method to return `undefined`
but it is clearer and safer to always check with `.has()` first.
PR Close#25445
In ES2015, classes could have been emitted as a variable declaration
initialized with a class expression. In certain situations, an intermediary
variable suffixed with `_1` is present such that the variable
declaration's initializer becomes a binary expression with its rhs being
the class expression, and its lhs being the identifier of the intermediate
variable. This structure was not recognized, resulting in such classes not
being considered as a class in `Esm2015ReflectionHost`.
As a consequence, the analysis of functions/methods that return a
`ModuleWithProviders` object did not take the methods of such classes into
account.
Another edge-case with such intermediate variable was that static
properties would not be considered as class members. A testcase was added
to prevent regressions.
Fixes#29078
PR Close#29119
Previously, several `ngtsc` and `ngcc` APIs dealing with class
declaration nodes used inconsistent types. For example, some methods of
the `DecoratorHandler` interface expected a `ts.Declaration` argument,
but actual `DecoratorHandler` implementations specified a stricter
`ts.ClassDeclaration` type.
As a result, the stricter methods would operate under the incorrect
assumption that their arguments were of type `ts.ClassDeclaration`,
while the actual arguments might be of different types (e.g. `ngcc`
would call them with `ts.FunctionDeclaration` or
`ts.VariableDeclaration` arguments, when compiling ES5 code).
Additionally, since we need those class declarations to be referenced in
other parts of the program, `ngtsc`/`ngcc` had to either repeatedly
check for `ts.isIdentifier(node.name)` or assume there was a `name`
identifier and use `node.name!`. While this assumption happens to be
true in the current implementation, working around type-checking is
error-prone (e.g. the assumption might stop being true in the future).
This commit fixes this by introducing a new type to be used for such
class declarations (`ts.Declaration & {name: ts.Identifier}`) and using
it consistently throughput the code.
PR Close#29209
Sometimes, in ESM5 code, aliases to exported variables are used internally
to refer to the exported value. This prevented some analysis from being
able to match up a reference to an export to the actual export itself.
For example in the following code:
```
var HttpClientXsrfModule = /** @class */ (function () {
function HttpClientXsrfModule() {
}
HttpClientXsrfModule_1 = HttpClientXsrfModule;
HttpClientXsrfModule.withOptions = function (options) {
if (options === void 0) { options = {}; }
return {
ngModule: HttpClientXsrfModule_1,
providers: [],
};
};
var HttpClientXsrfModule_1;
HttpClientXsrfModule = HttpClientXsrfModule_1 = tslib_1.__decorate([
NgModule({
providers: [],
})
], HttpClientXsrfModule);
return HttpClientXsrfModule;
}());
```
We were not able to tell that the `ngModule: HttpClientXsrfModule_1` property
assignment was actually meant to refer to the `function HttpClientXrsfModule()`
declaration. This caused the `ModuleWithProviders` processing to fail.
This commit ensures that we can compile typings files using the ESM5
format, so we can now update the examples boilerplate tool so that it
does not need to compile the ESM2015 format at all.
PR Close#29092