From 6bf543cb07e1950dcfc5508bc2ea15a1c1b30b72 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Fri, 11 Jul 2014 21:03:56 -0700
Subject: [PATCH] command/plan: default state path

---
 command/command.go      |  3 +++
 command/command_test.go | 12 ++++++++-
 command/plan.go         | 13 +++++++--
 command/plan_test.go    | 60 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 85 insertions(+), 3 deletions(-)

diff --git a/command/command.go b/command/command.go
index fd316f4b1..6ca862d83 100644
--- a/command/command.go
+++ b/command/command.go
@@ -9,6 +9,9 @@ import (
 	"github.com/mitchellh/cli"
 )
 
+// DefaultStateFilename is the default filename used for the state file.
+const DefaultStateFilename = "terraform.tfstate"
+
 func ContextArg(
 	path string,
 	statePath string,
diff --git a/command/command_test.go b/command/command_test.go
index e2165bafa..0f231ba90 100644
--- a/command/command_test.go
+++ b/command/command_test.go
@@ -10,7 +10,17 @@ import (
 )
 
 // This is the directory where our test fixtures are.
-const fixtureDir = "./test-fixtures"
+var fixtureDir = "./test-fixtures"
+
+func init() {
+	// Expand the fixture dir on init because we change the working
+	// directory in some tests.
+	var err error
+	fixtureDir, err = filepath.Abs(fixtureDir)
+	if err != nil {
+		panic(err)
+	}
+}
 
 func testFixturePath(name string) string {
 	return filepath.Join(fixtureDir, name)
diff --git a/command/plan.go b/command/plan.go
index e41466087..d1c24482f 100644
--- a/command/plan.go
+++ b/command/plan.go
@@ -27,7 +27,7 @@ func (c *PlanCommand) Run(args []string) int {
 	cmdFlags.BoolVar(&destroy, "destroy", false, "destroy")
 	cmdFlags.BoolVar(&refresh, "refresh", true, "refresh")
 	cmdFlags.StringVar(&outPath, "out", "", "path")
-	cmdFlags.StringVar(&statePath, "state", "", "path")
+	cmdFlags.StringVar(&statePath, "state", DefaultStateFilename, "path")
 	cmdFlags.Usage = func() { c.Ui.Error(c.Help()) }
 	if err := cmdFlags.Parse(args); err != nil {
 		return 1
@@ -51,6 +51,15 @@ func (c *PlanCommand) Run(args []string) int {
 		}
 	}
 
+	// If the default state path doesn't exist, ignore it.
+	if statePath != "" {
+		if _, err := os.Stat(statePath); err != nil {
+			if os.IsNotExist(err) && statePath == DefaultStateFilename {
+				statePath = ""
+			}
+		}
+	}
+
 	// Load up the state
 	var state *terraform.State
 	if statePath != "" {
@@ -70,7 +79,7 @@ func (c *PlanCommand) Run(args []string) int {
 
 	b, err := config.LoadDir(path)
 	if err != nil {
-		c.Ui.Error(fmt.Sprintf("Error loading blueprint: %s", err))
+		c.Ui.Error(fmt.Sprintf("Error loading config: %s", err))
 		return 1
 	}
 
diff --git a/command/plan_test.go b/command/plan_test.go
index 61c22b8a6..f31c82356 100644
--- a/command/plan_test.go
+++ b/command/plan_test.go
@@ -3,6 +3,7 @@ package command
 import (
 	"io/ioutil"
 	"os"
+	"path/filepath"
 	"reflect"
 	"testing"
 
@@ -207,3 +208,62 @@ func TestPlan_state(t *testing.T) {
 		t.Fatalf("bad: %#v", p.DiffState)
 	}
 }
+
+func TestPlan_stateDefault(t *testing.T) {
+	originalState := &terraform.State{
+		Resources: map[string]*terraform.ResourceState{
+			"test_instance.foo": &terraform.ResourceState{
+				ID:   "bar",
+				Type: "test_instance",
+			},
+		},
+	}
+
+	// Write the state file in a temporary directory with the
+	// default filename.
+	td, err := ioutil.TempDir("", "tf")
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	statePath := filepath.Join(td, DefaultStateFilename)
+
+	f, err := os.Create(statePath)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	err = terraform.WriteState(originalState, f)
+	f.Close()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	// Change to that directory
+	cwd, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	if err := os.Chdir(filepath.Dir(statePath)); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+	defer os.Chdir(cwd)
+
+	p := testProvider()
+	ui := new(cli.MockUi)
+	c := &PlanCommand{
+		ContextOpts: testCtxConfig(p),
+		Ui:          ui,
+	}
+
+	args := []string{
+		testFixturePath("plan"),
+	}
+	if code := c.Run(args); code != 0 {
+		t.Fatalf("bad: %d\n\n%s", code, ui.ErrorWriter.String())
+	}
+
+	// Verify that the provider was called with the existing state
+	expectedState := originalState.Resources["test_instance.foo"]
+	if !reflect.DeepEqual(p.DiffState, expectedState) {
+		t.Fatalf("bad: %#v", p.DiffState)
+	}
+}