fix #134 - include base_ref and head_ref in github context from the event json

pkg/runner/run_context.go

@@ -194,7 +194,7 @@ func (rc *RunContext) newStepExecutor(step *model.Step) common.Executor {
 			Outputs: make(map[string]string),
 		}
 
-		sc.setupEnv()(ctx)
+		_ = sc.setupEnv()(ctx)
 		rc.ExprEval = sc.NewExpressionEvaluator()
 
 		if !rc.EvalBool(sc.Step.If) {
@@ -327,6 +327,11 @@ type githubContext struct {
 }
 
 func (rc *RunContext) getGithubContext() *githubContext {
+	token, ok := rc.Config.Secrets["GITHUB_TOKEN"]
+	if !ok {
+		token = os.Getenv("GITHUB_TOKEN")
+	}
+
 	ghc := &githubContext{
 		Event:     make(map[string]interface{}),
 		EventPath: "/github/workflow/event.json",
@@ -334,9 +339,8 @@ func (rc *RunContext) getGithubContext() *githubContext {
 		RunID:     "1",
 		RunNumber: "1",
 		Actor:     "nektos/act",
-
 		EventName: rc.Config.EventName,
-		Token:     os.Getenv("GITHUB_TOKEN"),
+		Token:     token,
 		Workspace: "/github/workspace",
 		Action:    rc.CurrentStep,
 	}
@@ -367,9 +371,41 @@ func (rc *RunContext) getGithubContext() *githubContext {
 	if err != nil {
 		logrus.Error(err)
 	}
+
+	if ghc.EventName == "pull_request" {
+		ghc.BaseRef = asString(nestedMapLookup(ghc.Event, "pull_request", "base", "ref"))
+		ghc.HeadRef = asString(nestedMapLookup(ghc.Event, "pull_request", "head", "ref"))
+	}
+
 	return ghc
 }
 
+func asString(v interface{}) string {
+	if v == nil {
+		return ""
+	} else if s, ok := v.(string); ok {
+		return s
+	}
+	return ""
+}
+
+func nestedMapLookup(m map[string]interface{}, ks ...string) (rval interface{}) {
+	var ok bool
+
+	if len(ks) == 0 { // degenerate input
+		return nil
+	}
+	if rval, ok = m[ks[0]]; !ok {
+		return nil
+	} else if len(ks) == 1 { // we've reached the final key
+		return rval
+	} else if m, ok = rval.(map[string]interface{}); !ok {
+		return nil
+	} else { // 1+ more keys
+		return nestedMapLookup(m, ks[1:]...)
+	}
+}
+
 func (rc *RunContext) withGithubEnv(env map[string]string) map[string]string {
 	github := rc.getGithubContext()
 	env["HOME"] = "/github/home"

pkg/runner/runner_test.go

@@ -140,3 +140,40 @@ func TestRunEventSecrets(t *testing.T) {
 	err = runner.NewPlanExecutor(plan)(ctx)
 	assert.NilError(t, err, workflowPath)
 }
+
+func TestRunEventPullRequest(t *testing.T) {
+	if testing.Short() {
+		t.Skip("skipping integration test")
+	}
+
+	log.SetLevel(log.DebugLevel)
+	ctx := context.Background()
+
+	platforms := map[string]string{
+		"ubuntu-latest": "node:12.6-buster-slim",
+	}
+
+	workflowPath := "pull-request"
+	eventName := "pull_request"
+
+	workdir, err := filepath.Abs("testdata")
+	assert.NilError(t, err, workflowPath)
+
+	runnerConfig := &Config{
+		Workdir:         workdir,
+		EventName:       eventName,
+		EventPath:       filepath.Join(workdir, workflowPath, "event.json"),
+		Platforms:       platforms,
+		ReuseContainers: false,
+	}
+	runner, err := New(runnerConfig)
+	assert.NilError(t, err, workflowPath)
+
+	planner, err := model.NewWorkflowPlanner(fmt.Sprintf("testdata/%s", workflowPath))
+	assert.NilError(t, err, workflowPath)
+
+	plan := planner.PlanEvent(eventName)
+
+	err = runner.NewPlanExecutor(plan)(ctx)
+	assert.NilError(t, err, workflowPath)
+}

pkg/runner/testdata/pull-request/event.json

@@ -0,0 +1,10 @@
+{
+  "pull_request": {
+    "head": {
+      "ref": "sample-head-ref"
+    },
+    "base": {
+      "ref": "sample-base-ref"
+    }
+  }
+}

pkg/runner/testdata/pull-request/main.yaml

@@ -0,0 +1,10 @@
+name: basic
+on: pull_request
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - run: echo '${{github.ref}}' 
+      - run: echo '${{github.head_ref}}' | grep sample-head-ref
+      - run: echo '${{github.base_ref}}' | grep sample-base-ref

pkg/runner/testdata/secrets/.actrc

@@ -0,0 +1,4 @@
+-W .
+-s MY_SECRET
+-s MULTILINE_SECRET
+-s JSON_SECRET