fix: fail the run when matrix expansion fails (#1187)

A `GetMatrixes` error was logged and discarded, leaving a nil matrix list. That collapsed `maxParallel` to zero, so no executor was built and the parallel executor returned nil for an empty list: the job reported success without running anything.

It now fails the run. Every error it returns is a workflow validation failure that GitHub rejects too, so nothing that runs there starts failing here.

Reviewed-on: https://gitea.com/gitea/runner/pulls/1187
Reviewed-by: bircni <bircni@icloud.com>
Co-authored-by: silverwind <me@silverwind.io>

act/runner/max_parallel_test.go

@@ -8,6 +8,7 @@ import (
 
 	"gitea.dev/actionslib/pkg/model"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 	"go.yaml.in/yaml/v4"
 )
 
@@ -64,3 +65,20 @@ func TestMaxParallelStrategy(t *testing.T) {
 		})
 	}
 }
+
+func TestNewPlanExecutorInvalidMatrix(t *testing.T) {
+	var rawMatrix yaml.Node
+	require.NoError(t, rawMatrix.Encode(map[string]any{
+		"config": map[string]any{"nested": "value"},
+	}))
+
+	plan := &model.Plan{Stages: []*model.Stage{{Runs: []*model.Run{{
+		Workflow: &model.Workflow{Jobs: map[string]*model.Job{
+			"test": {Strategy: &model.Strategy{RawMatrix: rawMatrix}},
+		}},
+		JobID: "test",
+	}}}}}
+	runner := &runnerImpl{config: &Config{}}
+
+	require.ErrorContains(t, runner.NewPlanExecutor(plan)(t.Context()), "could not get job matrix:")
+}

act/runner/runner.go

@@ -207,7 +207,7 @@ func (runner *runnerImpl) NewPlanExecutor(plan *model.Plan) common.Executor {
 
 				matrixes, err := job.GetMatrixes()
 				if err != nil {
-					log.Errorf("Error while get job's matrix: %v", err)
+					return fmt.Errorf("could not get job matrix: %w", err)
 				}
 				log.Debugf("Job Matrices: %v", matrixes)