Previously, the compiler performed an incremental build by analyzing and
resolving all classes in the program (even unchanged ones) and then using
the dependency graph information to determine which .js files were stale and
needed to be re-emitted. This algorithm produced "correct" rebuilds, but the
cost of re-analyzing the entire program turned out to be higher than
anticipated, especially for component-heavy compilations.
To achieve performant rebuilds, it is necessary to reuse previous analysis
results if possible. Doing this safely requires knowing when prior work is
viable and when it is stale and needs to be re-done.
The new algorithm implemented by this commit is such:
1) Each incremental build starts with knowledge of the last known good
dependency graph and analysis results from the last successful build,
plus of course information about the set of files changed.
2) The previous dependency graph's information is used to determine the
set of source files which have "logically" changed. A source file is
considered logically changed if it or any of its dependencies have
physically changed (on disk) since the last successful compilation. Any
logically unchanged dependencies have their dependency information copied
over to the new dependency graph.
3) During the `TraitCompiler`'s loop to consider all source files in the
program, if a source file is logically unchanged then its previous
analyses are "adopted" (and their 'register' steps are run). If the file
is logically changed, then it is re-analyzed as usual.
4) Then, incremental build proceeds as before, with the new dependency graph
being used to determine the set of files which require re-emitting.
This analysis reuse avoids template parsing operations in many circumstances
and significantly reduces the time it takes ngtsc to rebuild a large
application.
Future work will increase performance even more, by tackling a variety of
other opportunities to reuse or avoid work.
PR Close#34288
In View Engine, providers which neither used `useValue`, `useClass`,
`useFactory` or `useExisting`, were interpreted differently.
e.g.
```
{provide: X} -> {provide: X, useValue: undefined}, // this is how it works in View Engine
{provide: X} -> {provide: X, useClass: X}, // this is how it works in Ivy
```
The missing-injectable migration should migrate such providers to the
explicit `useValue` provider. This ensures that there is no unexpected
behavioral change when updating to v9.
PR Close#33709
With the next version of the CLI we don't need to add logging for the description of the schematic as part of the schematic itself.
This is because now, the CLI will print the description defined in the `migrations.json` file.
See: https://github.com/angular/angular-cli/pull/15951
PR Close#33440
Currently the `missing-injectable` migration seems to add
`@Injectable()` to third-party classes in type definitions.
This not an issue in general since we do not generate broken code
by inserting a decorator into a type definition file. Though, we can
avoid adding the decorator since it won't have any effect and in
general we should not write to non source files of the compilation unit.
PR Close#33286
We should not migrate the reference from `useExisting`. This is because
developers can only use the `useExisting` value as a token. e.g.
```ts
@NgModule({
providers: [
{provide: AppRippleConfig, useValue: rippleOptions},
{provide: MAT_RIPPLE_OPTIONS, useExisting: AppRippleConfig},
]
})
export class AppModule {}
```
In the case above, nothing should be decorated with `@Injectable`. The
`AppRippleConfig` class is just used as a token for injection.
PR Close#33286
Currently the migration is unable to migrate instances where
the provider definition uses `forwardRef`. Since this is a
common pattern, we should support that from within the migration.
The solution to the problem is adding a foreign function resolver
to the `PartialEvaluator`. This basically matches the usage of
the static evaluation that is used by the ngtsc annotations.
PR Close#33286
Angular v9 schematics should print out a link to the migration
guide associated with each schematic. This way, users have an
easy way to find more information about the automatic code
transformations they will see with `ng update`.
PR Close#33258
Currenly the `missing-injectable` migration only migrates providers referenced from
`@NgModule` definitions. The schematic currently does not cover the migration for
providers referenced in `@Directive` or `@Component` definitions.
We need to handle the following keys for directives/components:
- `@Directive` -> `providers`
- `@Component` -> `providers` and `viewProviders`.
This commit ensures that the migration handles providers for these
definitions.
PR Close#33011
Current we need to create and override certain compiler host methods in every schematic because schematics use a virtual fs. We this change we extract this logic to a common util.
PR Close#32827
Moves all google3 migration tslint rules into a single directory.
This makes it easier to wire up multiple migration rules in
google3 without having to update the rule directories each time
a new migration is available.
PR Close#30956
Introduces a new migration schematic for adding the "@Injectable()"
decorator to provider classes which are currently not migrated. Previously
in ViewEngine, classes which are declared as providers sometimes don't
require the "@Injectable()" decorator
(e.g. https://stackblitz.com/edit/angular-hpo7gw)
With Ivy, provider classes need to be explicitly decorated with
the "@Injectable()" decorator if they are declared as providers
of a given module. This commit introduces a migration schematic
which automatically adds the explicit decorator to places where
the decorator is currently missing.
The migration logic is designed in a CLI devkit and TSlint agnostic
way so that we can also have this migration run as part of a public
CLI migration w/ `ng update`. This will be handled as part of a follow-up to reiterate on console output etc.
Resolves FW-1371
PR Close#30956
Alex Rickabaugh
Paul Gschwendtner
Alan Agius
Kara Erickson
Alan