fix: bias towards graph walk cancel over continue (#6210)
### Description
This PR does two things:
- Shuts down process manager in all the various failure modes
- Changes walker code to try to favor canceling the graph walk over
continuing the graph walk. These changes come down to usage of
[`biased;`](https://docs.rs/tokio/latest/tokio/macro.select.html#fairness).
There's some future work that needs to be done as I also discovered we
have an issue where we can accidentally spawn a child process if the
`manager.spawn()` call ends up getting delayed enough that it happens
[after this line in
`manager.close`](https://github.com/vercel/turbo/blob/main/crates/turborepo-lib/src/process/mod.rs#L122).
### Testing Instructions
Sadly, I haven't been able to get a red/green unit test so I need to
rely on manual testing.
#### Setup
- `npx create-turbo@canary testing pnpm`
- `pnpm rm turbo`
- Add failing `build` script to `ui`:
```
[1 olszewski@chriss-mbp] /tmp/testing $ git diff
diff --git a/packages/ui/package.json b/packages/ui/package.json
index 689c3ee..00ebf8c 100644
--- a/packages/ui/package.json
+++ b/packages/ui/package.json
@@ -5,6 +5,7 @@
"types": "./index.tsx",
"license": "MIT",
"scripts": {
+ "build": "echo 'failing'; exit 1",
"lint": "eslint .",
"generate:component": "turbo gen react-component"
},
```
#### Testing
On main, build a binary (`cargo build -p turbo`) and then use it to run
the failing tasks. You can run it a few times and you should see some
non-deterministic behavior which some of the time is incorrect where
tasks are `web#build` or `docs#build` are run even after the dependency
`ui#build` failed:
```
[0 olszewski@chriss-mbp] /tmp/testing $ turbo_dev build --experimental-rust-codepath
ui:build: cache miss, executing ef675823628c01fe
ui:build:
ui:build: > ui@0.0.0 build /private/tmp/testing/packages/ui
ui:build: > echo 'failing'; exit 1
ui:build:
ui:build: failing
ui:build: ELIFECYCLE Command failed with exit code 1.
ui:build: ERROR: command finished with error: command (/private/tmp/testing/packages/ui) pnpm run build exited (1)
ui#build: command (/private/tmp/testing/packages/ui) pnpm run build exited (1)
[1 olszewski@chriss-mbp] /tmp/testing $ turbo_dev build --experimental-rust-codepath
ui:build: cache miss, executing ef675823628c01fe
ui:build:
ui:build: > ui@0.0.0 build /private/tmp/testing/packages/ui
ui:build: > echo 'failing'; exit 1
ui:build:
ui:build: failing
ui:build: ELIFECYCLE Command failed with exit code 1.
ui:build: ERROR: command finished with error: command (/private/tmp/testing/packages/ui) pnpm run build exited (1)
docs:build: cache hit (outputs already on disk), replaying logs 804a78e82dc8e3c9
docs:build:
docs:build: > docs@1.0.0 build /private/tmp/testing/apps/docs
docs:build: > next build
docs:build:
docs:build: - info Creating an optimized production build...
docs:build: - info Compiled successfully
docs:build: - info Linting and checking validity of types...
docs:build: - info Collecting page data...
docs:build: - info Generating static pages (0/4)
docs:build: - info Generating static pages (1/4)
docs:build: - info Generating static pages (2/4)
docs:build: - info Generating static pages (3/4)
docs:build: - info Generating static pages (4/4)
docs:build: - info Finalizing page optimization...
docs:build:
docs:build: Route (app) Size First Load JS
docs:build: ┌ ○ / 5.52 kB 84 kB
docs:build: └ ○ /favicon.ico 0 B 0 B
docs:build: + First Load JS shared by all 78.5 kB
docs:build: ├ chunks/934-196dcc5a61008b80.js 26.1 kB
docs:build: ├ chunks/c260e7fb-1dc88cd74c938f5d.js 50.5 kB
docs:build: ├ chunks/main-app-dc37cd09df02200e.js 219 B
docs:build: └ chunks/webpack-46498be4babc7638.js 1.68 kB
docs:build:
docs:build: Route (pages) Size First Load JS
docs:build: ─ ○ /404 182 B 76.5 kB
docs:build: + First Load JS shared by all 76.3 kB
docs:build: ├ chunks/framework-eb124dc7acb3bb04.js 45.1 kB
docs:build: ├ chunks/main-15364e85b6f1124e.js 29.4 kB
docs:build: ├ chunks/pages/_app-82ff52170628f1f6.js 191 B
docs:build: └ chunks/webpack-46498be4babc7638.js 1.68 kB
docs:build:
docs:build: ○ (Static) automatically rendered as static HTML (uses no initial props)
docs:build:
ui#build: command (/private/tmp/testing/packages/ui) pnpm run build exited (1)
```
Now checkout this PR and build a `turbo` binary. Running `turbo build`
in the repo we set up should now be deterministic and only `ui#build`
will be run.
```
[1 olszewski@chriss-mbp] /tmp/testing $ turbo_dev build --experimental-rust-codepath
ui:build: cache miss, executing ef675823628c01fe
ui:build:
ui:build: > ui@0.0.0 build /private/tmp/testing/packages/ui
ui:build: > echo 'failing'; exit 1
ui:build:
ui:build: failing
ui:build: ELIFECYCLE Command failed with exit code 1.
ui:build: ERROR: command finished with error: command (/private/tmp/testing/packages/ui) pnpm run build exited (1)
ui#build: command (/private/tmp/testing/packages/ui) pnpm run build exited (1)
```
Closes TURBO-1489
---------
Co-authored-by: Chris Olszewski <Chris Olszewski>
