A composite action's `RunContext` is **seeded with its parent's `Masks` slice** in `newCompositeRunContext`. After the composite finished running, the *entire* `compositeRC.Masks` (the seeded parent masks plus any added during the run) was appended straight back into the parent:
```go
rc.Masks = append(rc.Masks, compositeRC.Masks...)
```
Because the composite already contained the parent's masks, every composite action roughly **doubled** the parent's `Masks` length. With many nested/repeated composite actions this grows exponentially:
```
before=1152 after=2304 compositeLen=1152
before=2304 after=4608 compositeLen=2304
before=4608 after=9216 compositeLen=4608
...
```
### Impact
The bloated `Masks` slice made per-log-line secret redaction (`strings.makeGenericReplacer`, rebuilt per line since #1001) extremely slow. Log writes fell behind enough to keep subprocess pipes open after the process had already exited, surfacing as seemingly random CI failures — most often in later steps of mask-heavy workflows:
```
Error: exec: WaitDelay expired before I/O complete
```
The split of `cmd.Run()` into `cmd.Start()` + `cmd.Wait()` (#883) is what turned this long-standing latency into a hard failure.
### Fix
Only append masks that aren't already present in the parent, via a small `appendUniqueMasks` helper. This keeps the mask count bounded by the number of *distinct* secrets instead of growing exponentially.
I kept `Masks` as a `[]string` rather than switching to a set type, since it's passed by pointer to loggers across `logger.go`, `run_context.go`, and `runner.go` — a type change would be a much wider, riskier refactor. The `O(n·m)` dedup is harmless precisely because `n` now stays small.
Fixes #1054Reviewed-on: https://gitea.com/gitea/runner/pulls/1059
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Merges the `gitea.com/gitea/act` fork into this repository as the `act/`
directory and consumes it as a local package. The `replace github.com/nektos/act
=> gitea.com/gitea/act` directive is removed; act's dependencies are merged
into the root `go.mod`.
- Imports rewritten: `github.com/nektos/act/pkg/...` → `gitea.com/gitea/act_runner/act/...`
(flattened — `pkg/` boundary dropped to match the layout forgejo-runner adopted).
- Dropped act's CLI (`cmd/`, `main.go`) and all upstream project files; kept
the library tree + `LICENSE`.
- Added `// Copyright <year> The Gitea Authors ...` / `// Copyright <year> nektos`
headers to 104 `.go` files.
- Pre-existing act lint violations annotated inline with
`//nolint:<linter> // pre-existing issue from nektos/act`.
`.golangci.yml` is unchanged vs `main`.
- Makefile test target: `-race -short` (matches forgejo-runner).
- Pre-existing integration test failures fixed: race in parallel executor
(atomic counters); TestSetupEnv / command_test / expression_test /
run_context_test updated to match gitea fork runtime; TestJobExecutor and
TestActionCache gated on `testing.Short()`.
Full `gitea/act` commit history is reachable via the second parent.
Co-Authored-By: Claude (Opus 4.7) <noreply@anthropic.com>
