command: plan supports detailed exit code

command/plan.go

@@ -16,7 +16,7 @@ type PlanCommand struct {
 }
 
 func (c *PlanCommand) Run(args []string) int {
-	var destroy, refresh bool
+	var destroy, refresh, detailed bool
 	var outPath string
 	var moduleDepth int
 
@@ -29,6 +29,7 @@ func (c *PlanCommand) Run(args []string) int {
 	cmdFlags.StringVar(&outPath, "out", "", "path")
 	cmdFlags.StringVar(&c.Meta.statePath, "state", DefaultStateFilename, "path")
 	cmdFlags.StringVar(&c.Meta.backupPath, "backup", "", "path")
+	cmdFlags.BoolVar(&detailed, "detailed-exitcode", false, "detailed-exitcode")
 	cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
 	if err := cmdFlags.Parse(args); err != nil {
 		return 1
@@ -129,6 +130,9 @@ func (c *PlanCommand) Run(args []string) int {
 		ModuleDepth: moduleDepth,
 	}))
 
+	if detailed {
+		return 2
+	}
 	return 0
 }
 
@@ -152,6 +156,12 @@ Options:
   -destroy            If set, a plan will be generated to destroy all resources
                       managed by the given configuration and state.
 
+  -detailed-exitcode  Return detailed exit codes when the command exits. This
+                      will change the meaning of exit codes to:
+                      0 - Succeeded, diff is empty (no changes)
+                      1 - Errored
+                      2 - Succeeded, there is a diff
+
   -input=true         Ask for input for variables if not directly set.
 
   -module-depth=n     Specifies the depth of modules to show in the output.

command/plan_test.go

@@ -567,6 +567,56 @@ func TestPlan_disableBackup(t *testing.T) {
 	}
 }
 
+func TestPlan_detailedExitcode(t *testing.T) {
+	cwd, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	if err := os.Chdir(testFixturePath("plan")); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	defer os.Chdir(cwd)
+
+	p := testProvider()
+	ui := new(cli.MockUi)
+	c := &PlanCommand{
+		Meta: Meta{
+			ContextOpts: testCtxConfig(p),
+			Ui:          ui,
+		},
+	}
+
+	args := []string{"-detailed-exitcode"}
+	if code := c.Run(args); code != 2 {
+		t.Fatalf("bad: %d\n\n%s", code, ui.ErrorWriter.String())
+	}
+}
+
+func TestPlan_detailedExitcode_emptyDiff(t *testing.T) {
+	cwd, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	if err := os.Chdir(testFixturePath("plan-emptydiff")); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	defer os.Chdir(cwd)
+
+	p := testProvider()
+	ui := new(cli.MockUi)
+	c := &PlanCommand{
+		Meta: Meta{
+			ContextOpts: testCtxConfig(p),
+			Ui:          ui,
+		},
+	}
+
+	args := []string{"-detailed-exitcode"}
+	if code := c.Run(args); code != 0 {
+		t.Fatalf("bad: %d\n\n%s", code, ui.ErrorWriter.String())
+	}
+}
+
 const planVarFile = `
 foo = "bar"
 `