Function TestScanDeltaEmission

agent/agentgit/agentgit_test.go:232–270

(t *testing.T)

}

func TestScanDeltaEmission(t *testing.T) {
	t.Parallel()

	repoDir := initTestRepo(t)
	logger := slogtest.Make(t, nil)

	h := agentgit.NewHandler(logger)

	// Create a dirty file.
	dirtyFile := filepath.Join(repoDir, "dirty.go")
	require.NoError(t, os.WriteFile(dirtyFile, []byte("package dirty\n"), 0o600))

	h.Subscribe([]string{dirtyFile})
	ctx := context.Background()

	// First scan — returns all files (no previous snapshot).
	msg1 := h.Scan(ctx)
	require.NotNil(t, msg1)
	require.Len(t, msg1.Repositories, 1)

	// Second scan with no changes. Should emit a heartbeat with a
	// fresh ScannedAt but no repositories. This lets the UI's
	// "checked Ns ago" label stay honest on an idle clean repo.
	msg2 := h.Scan(ctx)
	require.NotNil(t, msg2, "heartbeat should fire even with no delta")
	require.NotNil(t, msg2.ScannedAt)
	require.Empty(t, msg2.Repositories, "heartbeat must not report per-repo changes")

	// Revert the dirty file (make repo clean).
	require.NoError(t, os.Remove(dirtyFile))

	// Third scan — should emit a "clean" delta for dirty.go.
	msg3 := h.Scan(ctx)
	require.NotNil(t, msg3)
	require.Len(t, msg3.Repositories, 1)

	// The file was reverted, so it should no longer appear in the diff.
	require.NotContains(t, msg3.Repositories[0].UnifiedDiff, "dirty.go")
}

// TestScanHeartbeatOnCleanRepo pins the heartbeat contract: while any
// repo is subscribed, every scan emits a non-nil message with a fresh