From 5f895270493d07c7782875e0a11e30af0c05491f Mon Sep 17 00:00:00 2001
From: Luke Kysow <1034429+lkysow@users.noreply.github.com>
Date: Fri, 7 Dec 2018 10:15:42 -0600
Subject: [PATCH] Return plan output on error.

If terraform plan returns an error, we still want to print the output to
the pull request.
---
 server/events/runtime/plan_step_runner.go     |  2 +-
 .../events/runtime/plan_step_runner_test.go   | 61 ++++++++++++++++++-
 2 files changed, 60 insertions(+), 3 deletions(-)

diff --git a/server/events/runtime/plan_step_runner.go b/server/events/runtime/plan_step_runner.go
index 3a393cdc5..b731544e0 100644
--- a/server/events/runtime/plan_step_runner.go
+++ b/server/events/runtime/plan_step_runner.go
@@ -39,7 +39,7 @@ func (p *PlanStepRunner) Run(ctx models.ProjectCommandContext, extraArgs []strin
 	planCmd := p.buildPlanCmd(ctx, extraArgs, path)
 	output, err := p.TerraformExecutor.RunCommandWithVersion(ctx.Log, filepath.Clean(path), planCmd, tfVersion, ctx.Workspace)
 	if err != nil {
-		return "", err
+		return output, err
 	}
 	return p.fmtPlanOutput(output), nil
 }
diff --git a/server/events/runtime/plan_step_runner_test.go b/server/events/runtime/plan_step_runner_test.go
index d2f5c41bf..7e5556758 100644
--- a/server/events/runtime/plan_step_runner_test.go
+++ b/server/events/runtime/plan_step_runner_test.go
@@ -536,8 +536,19 @@ Terraform will perform the following actions:
 		AnyStringSlice(),
 		matchers2.AnyPtrToGoVersionVersion(),
 		AnyString())).
-		ThenReturn(rawOutput, nil)
-	actOutput, err := s.Run(models.ProjectCommandContext{}, nil, "")
+		Then(func(params []Param) ReturnValues {
+			// This code allows us to return different values depending on the
+			// tf command being run while still using the wildcard matchers above.
+			tfArgs := params[2].([]string)
+			if stringSliceEquals(tfArgs, []string{"workspace", "show"}) {
+				return []ReturnValue{"default", nil}
+			} else if tfArgs[0] == "plan" {
+				return []ReturnValue{rawOutput, nil}
+			} else {
+				return []ReturnValue{"", errors.New("unexpected call to RunCommandWithVersion")}
+			}
+		})
+	actOutput, err := s.Run(models.ProjectCommandContext{Workspace: "default"}, nil, "")
 	Ok(t, err)
 	Equals(t, `
 An execution plan has been generated and is shown below.
@@ -560,3 +571,49 @@ Terraform will perform the following actions:
 - aws_security_group_rule.allow_all
 `, actOutput)
 }
+
+// Test that even if there's an error, we get the returned output.
+func TestRun_OutputOnErr(t *testing.T) {
+	RegisterMockTestingT(t)
+	terraform := mocks.NewMockClient()
+	tfVersion, _ := version.NewVersion("0.10.0")
+	s := runtime.PlanStepRunner{
+		TerraformExecutor: terraform,
+		DefaultTFVersion:  tfVersion,
+	}
+	expOutput := "expected output"
+	expErrMsg := "error!"
+	When(terraform.RunCommandWithVersion(
+		matchers.AnyPtrToLoggingSimpleLogger(),
+		AnyString(),
+		AnyStringSlice(),
+		matchers2.AnyPtrToGoVersionVersion(),
+		AnyString())).
+		Then(func(params []Param) ReturnValues {
+			// This code allows us to return different values depending on the
+			// tf command being run while still using the wildcard matchers above.
+			tfArgs := params[2].([]string)
+			if stringSliceEquals(tfArgs, []string{"workspace", "show"}) {
+				return []ReturnValue{"default\n", nil}
+			} else if tfArgs[0] == "plan" {
+				return []ReturnValue{expOutput, errors.New(expErrMsg)}
+			} else {
+				return []ReturnValue{"", errors.New("unexpected call to RunCommandWithVersion")}
+			}
+		})
+	actOutput, actErr := s.Run(models.ProjectCommandContext{Workspace: "default"}, nil, "")
+	ErrEquals(t, expErrMsg, actErr)
+	Equals(t, expOutput, actOutput)
+}
+
+func stringSliceEquals(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i, v := range a {
+		if v != b[i] {
+			return false
+		}
+	}
+	return true
+}