Fix incorrect concurrency check (#37205) (#37215)

Backport #37205 by @Zettat123

This bug was identified in
https://github.com/go-gitea/gitea/pull/37119/changes#diff-37655a02d5a44d5c0e3e19c75fb58adb47a8e7835cbd619345d5b556292935a7L180

Co-authored-by: Zettat123 <zettat123@gmail.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

services/actions/job_emitter_test.go

@@ -7,6 +7,8 @@ import (
 	"testing"
 
 	actions_model "code.gitea.io/gitea/models/actions"
+	"code.gitea.io/gitea/models/db"
+	"code.gitea.io/gitea/models/unittest"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -134,3 +136,68 @@ jobs:
 		})
 	}
 }
+
+// Test_checkRunConcurrency_NoDuplicateConcurrencyGroupCheck verifies that when a run's
+// ConcurrencyGroup has already been checked at the run level, the same group is not
+// re-checked for individual jobs.
+func Test_checkRunConcurrency_NoDuplicateConcurrencyGroupCheck(t *testing.T) {
+	assert.NoError(t, unittest.PrepareTestDatabase())
+	ctx := t.Context()
+
+	// Run A: the triggering run with a concurrency group.
+	runA := &actions_model.ActionRun{
+		RepoID:           4,
+		OwnerID:          1,
+		TriggerUserID:    1,
+		WorkflowID:       "test.yml",
+		Index:            9901,
+		Ref:              "refs/heads/main",
+		Status:           actions_model.StatusRunning,
+		ConcurrencyGroup: "test-cg",
+	}
+	assert.NoError(t, db.Insert(ctx, runA))
+
+	// A done job for run A with the same ConcurrencyGroup.
+	// This triggers the job-level concurrency check in checkRunConcurrency.
+	jobADone := &actions_model.ActionRunJob{
+		RunID:            runA.ID,
+		RepoID:           4,
+		OwnerID:          1,
+		JobID:            "job1",
+		Name:             "job1",
+		Status:           actions_model.StatusSuccess,
+		ConcurrencyGroup: "test-cg",
+	}
+	assert.NoError(t, db.Insert(ctx, jobADone))
+
+	// Blocked run B competing for the same concurrency group.
+	runB := &actions_model.ActionRun{
+		RepoID:           4,
+		OwnerID:          1,
+		TriggerUserID:    1,
+		WorkflowID:       "test.yml",
+		Index:            9902,
+		Ref:              "refs/heads/main",
+		Status:           actions_model.StatusBlocked,
+		ConcurrencyGroup: "test-cg",
+	}
+	assert.NoError(t, db.Insert(ctx, runB))
+
+	// A blocked job belonging to run B (no job-level concurrency group).
+	jobBBlocked := &actions_model.ActionRunJob{
+		RunID:   runB.ID,
+		RepoID:  4,
+		OwnerID: 1,
+		JobID:   "job1",
+		Name:    "job1",
+		Status:  actions_model.StatusBlocked,
+	}
+	assert.NoError(t, db.Insert(ctx, jobBBlocked))
+
+	jobs, _, err := checkRunConcurrency(ctx, runA)
+	assert.NoError(t, err)
+
+	if assert.Len(t, jobs, 1) {
+		assert.Equal(t, jobBBlocked.ID, jobs[0].ID)
+	}
+}