Document stream ownership and v2 early-close behavior#57
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Pull request overview
This PR documents a behavioral difference between go-pipe v1 and v2 around early-consumer exit and producer-side pipe write errors, and adds/adjusts tests to validate the v2 behavior (including how IgnoreError(..., IsPipeError) can be used to safely ignore these errors for stateless producers).
Changes:
- Document v2’s more direct surfacing of producer-side pipe errors when downstream stages stop reading early, with guidance/patterns for stateful producers.
- Remove Windows-specific skips from several pipeline tests that shell out to Unix utilities, and drop the
runtimeimport. - Add new tests asserting (a) Go producers can observe pipe errors when a command exits without reading stdin and (b)
IgnoreError(IsPipeError)allows stateful producers to finish processing.
Show a summary per file
| File | Description |
|---|---|
| README.md | Adds v1→v2 migration note explaining early-close pipe errors and how to handle them. |
| pipe/pipeline_test.go | Updates pipeline tests (removes Windows skips) and adds new coverage for producer-side pipe errors + IgnoreError(IsPipeError) behavior. |
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- Files reviewed: 2/2 changed files
- Comments generated: 9
Replace Stage.Start close flags with InputStream and OutputStream types. The endpoint constructors encode whether a stream is closing while preserving the underlying reader/writer type. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Add regression coverage for the go-pipe v2 behavior where a Go producer can see a pipe error directly when a downstream command exits without fully reading stdin. This documents the visible semantic change from v1 to v2. Also, we add an example that demonstrates correctly handling downstream early exit in a stateful producer.
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Explain that go-pipe v1 could hide producer-side pipe write errors as an implementation detail of the command stdin-copy path, while v2 exposes those errors more directly. Document the migration patterns for stateless and stateful producers.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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mhagger
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LGTM as another step towards v2 👍
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This branch builds on
znull/stage-v2-cleanby introducing explicit endpoint stream ownership types and documenting the behavior changes that fall out of the v2 pipeline wiring.It replaces boolean stdin/stdout close flags in the
Stagestartup contract withInputStreamandOutputStreamtypes, so ownership is visible in the value passed to each stage. The stream ownership docs now spell out when stages must close closing streams, includingStart()error paths, and the startup cleanup code has been aligned so the pipeline only closes streams it still owns.WithStdoutCloseris still closed when startup fails before the final stage receives it.It also documents v2 early-close producer behavior. A downstream stage can stop reading before all input is consumed, causing upstream writes to surface
EPIPE,SIGPIPE, orio.ErrClosedPipe; README and public godoc now point callers atIgnoreError(stage, IsPipeError)for stateless producers and call out the extra consistency work required for stateful producers.