From f2c15074ac70f90aaa5126db3a6a625dbabaa5ed Mon Sep 17 00:00:00 2001
From: Wink Saville <wink@saville.com>
Date: Tue, 12 Jan 2021 16:02:54 -0800
Subject: [PATCH] Fix issue 416 (#423)

This is a solution to issue #416 where environment variables created or
changed in the previous step are not usable in the next step because
the rc.ExprEval is from the beginning of the previous step.

This change refactors setupEnv so that before interpolating the environment
variables a NewExpressionEvaluator is created.


Fixes: 416
---
 pkg/runner/run_context.go  | 12 +++-----
 pkg/runner/step_context.go | 58 +++++++++++++++++++++++++-------------
 2 files changed, 43 insertions(+), 27 deletions(-)

diff --git a/pkg/runner/run_context.go b/pkg/runner/run_context.go
index 0baf54e..6c99e6f 100644
--- a/pkg/runner/run_context.go
+++ b/pkg/runner/run_context.go
@@ -202,15 +202,11 @@ func (rc *RunContext) newStepExecutor(step *model.Step) common.Executor {
 			Outputs: make(map[string]string),
 		}
 
-		_ = sc.setupEnv()(ctx)
-
-		if sc.Env != nil {
-			err := rc.JobContainer.UpdateFromGithubEnv(&sc.Env)(ctx)
-			if err != nil {
-				return err
-			}
+		exprEval, err := sc.setupEnv(ctx)
+		if err != nil {
+			return err
 		}
-		rc.ExprEval = sc.NewExpressionEvaluator()
+		rc.ExprEval = exprEval;
 
 		runStep, err := rc.EvalBool(sc.Step.If)
 		if err != nil {
diff --git a/pkg/runner/step_context.go b/pkg/runner/step_context.go
index e135c9b..56e51a5 100644
--- a/pkg/runner/step_context.go
+++ b/pkg/runner/step_context.go
@@ -79,33 +79,53 @@ func (sc *StepContext) Executor() common.Executor {
 	return common.NewErrorExecutor(fmt.Errorf("Unable to determine how to run job:%s step:%+v", rc.Run, step))
 }
 
-func (sc *StepContext) setupEnv() common.Executor {
+func (sc *StepContext) mergeEnv() map[string]string {
 	rc := sc.RunContext
 	job := rc.Run.Job()
 	step := sc.Step
-	return func(ctx context.Context) error {
-		var env map[string]string
-		c := job.Container()
-		if c != nil {
-			env = mergeMaps(rc.GetEnv(), c.Env, step.GetEnv())
-		} else {
-			env = mergeMaps(rc.GetEnv(), step.GetEnv())
-		}
 
-		if (rc.ExtraPath != nil) && (len(rc.ExtraPath) > 0) {
-			s := append(rc.ExtraPath, `/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin`)
-			env["PATH"] = strings.Join(s, `:`)
-		}
+	var env map[string]string
+	c := job.Container()
+	if c != nil {
+		env = mergeMaps(rc.GetEnv(), c.Env, step.GetEnv())
+	} else {
+		env = mergeMaps(rc.GetEnv(), step.GetEnv())
+	}
 
-		for k, v := range env {
-			env[k] = rc.ExprEval.Interpolate(v)
-		}
-		sc.Env = rc.withGithubEnv(env)
-		log.Debugf("setupEnv => %v", sc.Env)
-		return nil
+	if (rc.ExtraPath != nil) && (len(rc.ExtraPath) > 0) {
+		s := append(rc.ExtraPath, `/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin`)
+		env["PATH"] = strings.Join(s, `:`)
+	}
+
+	sc.Env = rc.withGithubEnv(env)
+	return env
+}
+
+
+func (sc *StepContext) interpolateEnv(exprEval ExpressionEvaluator) {
+	for k, v := range sc.Env {
+		sc.Env[k] = exprEval.Interpolate(v)
 	}
 }
 
+
+func (sc *StepContext) setupEnv(ctx context.Context) (ExpressionEvaluator, error) {
+	rc := sc.RunContext
+	sc.Env = sc.mergeEnv()
+	if sc.Env != nil {
+		err := rc.JobContainer.UpdateFromGithubEnv(&sc.Env)(ctx)
+		if err != nil {
+			return nil, err
+		}
+	}
+	evaluator := sc.NewExpressionEvaluator()
+	sc.interpolateEnv(evaluator)
+
+	log.Debugf("setupEnv: %v", sc.Env)
+	return evaluator, nil
+}
+
+
 func (sc *StepContext) setupShellCommand() common.Executor {
 	rc := sc.RunContext
 	step := sc.Step