This finder is designed to only process entry-points that are reachable
by the program defined by a tsconfig.json file.
It is triggered by calling `mainNgcc()` with the `findEntryPointsFromTsConfigProgram`
option set to true. It is ignored if a `targetEntryPointPath` has been
provided as well.
It is triggered from the command line by adding the `--use-program-dependencies`
option, which is also ignored if the `--target` option has been provided.
Using this option can speed up processing in cases where there is a large
number of dependencies installed but only a small proportion of the
entry-points are actually imported into the application.
PR Close#37075
This commit will store a cached copy of the parsed tsconfig
that can be reused if the tsconfig path is the same.
This will improve the ngcc "noop" case, where there is no processing
to do, when the entry-points have already been processed.
Previously we were parsing this config every time we checked for
entry-points to process, which can take up to seconds in some
cases.
Resolves#36882
PR Close#37417
Now that `ngcc/src/ngcc_options` imports `FileWriter` type, there is a
circular dependency detected by the `ts-circular-deps:check` lint check:
```
ngcc/src/ngcc_options.ts
→ ngcc/src/writing/file_writer.ts
→ ngcc/src/packages/entry_point_bundle.ts
→ ngcc/src/ngcc_options.ts
```
This commit moves the `PathMappings` type (and related helpers) to a
separate file to avoid the circular dependency.
NOTE:
The circular dependency was only with taking types into account. There
was no circular dependency for the actual (JS) code.
PR Close#36626
Previously, when running in parallel mode and a worker process crashed
while processing a task, it was not possible for ngcc to continue
without risking ending up with a corrupted entry-point and therefore it
exited with an error. This, for example, could happen when a worker
process received a `SIGKILL` signal, which was frequently observed in CI
environments. This was probably the result of Docker killing processes
due to increased memory pressure.
One factor that amplifies the problem under Docker (which is often used
in CI) is that it is not possible to distinguish between the available
CPU cores on the host machine and the ones made available to Docker
containers, thus resulting in ngcc spawning too many worker processes.
This commit addresses these issues in the following ways:
1. We take advantage of the fact that files are written to disk only
after an entry-point has been fully analyzed/compiled. The master
process can now determine whether a worker process has not yet
started writing files to disk (even if it was in the middle of
processing a task) and just put the task back into the tasks queue if
the worker process crashes.
2. The master process keeps track of the transformed files that a worker
process will attempt to write to disk. If the worker process crashes
while writing files, the master process can revert any changes and
put the task back into the tasks queue (without risking corruption).
3. When a worker process crashes while processing a task (which can be a
result of increased memory pressure or too many worker processes),
the master process will not try to re-spawn it. This way the number
or worker processes is gradually adjusted to a level that can be
accomodated by the system's resources.
Examples of ngcc being able to recover after a worker process crashed:
- While idling: https://circleci.com/gh/angular/angular/682197
- While compiling: https://circleci.com/gh/angular/angular/682209
- While writing files: https://circleci.com/gh/angular/angular/682267
Jira issue: [FW-2008](https://angular-team.atlassian.net/browse/FW-2008)
Fixes#36278
PR Close#36626
