## Problem
Several runner code paths could drop the **tail** of a step's log output, so a
failing (or cancelled) step would show output that is missing its last line(s).
This was observed in practice and traced to four independent issues.
## Root causes & fixes
### 1. Trailing line without a newline was never flushed
`common.lineWriter` buffers output until it sees a `\n`. A final line **without**
a trailing newline (e.g. an error message printed right before a process exits,
a panic, `printf` without `\n`) stayed in the internal buffer and was never
emitted — the writer exposed no flush at all.
- Added `lineWriter.Flush()` (idempotent), a `Flusher` interface, and a
`FlushWriter(io.Writer)` helper.
- Flush at every stream EOF: the exec copy goroutine, the container `attach()`
streaming goroutine, and at step end (`useStepLogger`).
### 2. Cancellation/timeout truncated output
`waitForCommand` returned immediately on `ctx.Done()` and abandoned the
output-copy goroutine, losing output the command had already produced. It now
drains with a bounded grace period before returning. The response channel is
buffered so the goroutine can't leak if the drain times out.
### 3. `attach()` raced the final bytes
Container output was streamed in a fire-and-forget goroutine that `wait()` did
not synchronize with, so the step could proceed before the last bytes were
written. `wait()` now blocks on the streaming goroutine (bounded) so output is
fully drained and flushed first.
### 4. `::stop-commands::` silently dropped lines from the step log
Lines between `::stop-commands::<token>` and its end token were echoed without
the `raw_output` field **and** short-circuited the handler chain (`return false`),
so they never reached the step log (non-raw entries aren't appended while a step
is running). Now returns `true` so they are still captured.
Reviewed-on: https://gitea.com/gitea/runner/pulls/1028
Reviewed-by: Zettat123 <39446+zettat123@noreply.gitea.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>
