We now create 2 programs with exactly the same fileNames and
exactly the same `import` / `export` declarations,
allowing TS to reuse the structure of first program
completely. When passing in an oldProgram and the files didn’t change,
TS can also reuse the old program completely.
This is possible buy adding generated files to TS
in `host.geSourceFile` via `ts.SourceFile.referencedFiles`.
This commit also:
- has a minor side effect on how we generate shared stylesheets:
- previously every import in a stylesheet would generate a new
`.ngstyles.ts` file.
- now, we only generate 1 `.ngstyles.ts` file per entry in `@Component.styleUrls`.
This was required as we need to be able to determine the program files
without loading the resources (which can be async).
- makes all angular related methods in `CompilerHost`
optional, allowing to just use a regular `ts.CompilerHost` as `CompilerHost`.
- simplifies the logic around `Compiler.analyzeNgModules` by introducing `NgAnalyzedFile`.
Perf impact: 1.5s improvement in compiling angular io
PR Close#19275
- temporarily keeps the old sources under packages/tsc-wrapped
until the build scripts are changed to use compiler-cli everywhere.
- removes the compiler options `disableTransformerPipeline` that was introduced
in a previous beta of Angular 5, i.e. the transformer based compiler
is now always enabled.
PR Close#18966
With this commit the compiler will "lower" expressions into exported
variables for values the compiler does not need to know statically
in order to be able to generate a factory. For example:
```
providers: [{provider: 'token', useValue: calculated()}]
```
produced an error as the expression `calculated()` is not supported
by the compiler because `calculated` is not a
[known function](https://angular.io/guide/metadata#annotationsdecorators)
With this commit this is rewritten, during emit of the .js file, into
something like:
```
export var ɵ0 = calculated();
...
provdiers: [{provider: 'token', useValue: ɵ0}]
```
The compiler then will now generate a reference to the exported `ɵ0`
instead of failing to evaluate `calculated()`.
PR Close#18905
With this commit the compiler will "lower" expressions into exported
variables for values the compiler does not need to know statically
in order to be able to generate a factory. For example:
```
providers: [{provider: 'token', useValue: calculated()}]
```
produced an error as the expression `calculated()` is not supported
by the compiler because `calculated` is not a
[known function](https://angular.io/guide/metadata#annotationsdecorators)
With this commit this is rewritten, during emit of the .js file, into
something like:
```
export var ɵ0 = calculated();
...
provdiers: [{provider: 'token', useValue: ɵ0}]
```
The compiler then will now generate a reference to the exported `ɵ0`
instead of failing to evaluate `calculated()`.
PR Close#18905
Previously, we only did this when setting the `generateCodeForLibraries: false`.
This is needed so that libraries compiled with `generateCodeForLibraries: true` can be used as dependencies of other compilation units.
PR Close#18788
The source map does not currently work with the transformer pipeline.
It will be re-enabled after TypeScript 2.4 is made the min version.
To revert to the former compiler, use the `disableTransformerPipeline` in
tsconfig.json:
```
{
"angularCompilerOptions": {
"disableTransformerPipeline": true
}
}
```