From 87f4b49f853b92b4237915473bb1ab4d6608e3a3 Mon Sep 17 00:00:00 2001
From: Mitchell Hashimoto <mitchell.hashimoto@gmail.com>
Date: Tue, 5 Aug 2014 10:12:35 -0700
Subject: [PATCH] terraform: multi-variables work with count = 1 [GH-115]

---
 CHANGELOG.md                                  |  1 +
 terraform/context.go                          |  7 ++++++
 terraform/context_test.go                     | 23 +++++++++++++++++++
 terraform/terraform_test.go                   | 16 +++++++++++++
 .../plan-var-multi-count-one/main.tf          |  9 ++++++++
 5 files changed, 56 insertions(+)
 create mode 100644 terraform/test-fixtures/plan-var-multi-count-one/main.tf

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 2d83a40cf2d9..f87164ade192 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -13,6 +13,7 @@ IMPROVEMENTS:
 BUG FIXES:
 
   * core: Default variable file "terraform.tfvars" is auto-loaded. [GH-59]
+  * core: Multi-variables (`foo.*.bar`) work even when `count = 1`. [GH-115]
   * providers/cloudflare: Include the proper bins so the cloudflare
       provider is compiled
   * providers/aws: Engine version for RDS now properly set [GH-118]
diff --git a/terraform/context.go b/terraform/context.go
index 3b837c6d89e8..32d93cafe306 100644
--- a/terraform/context.go
+++ b/terraform/context.go
@@ -406,6 +406,13 @@ func (c *Context) computeResourceMultiVariable(
 	var values []string
 	for i := 0; i < cr.Count; i++ {
 		id := fmt.Sprintf("%s.%d", v.ResourceId(), i)
+
+		// If we're dealing with only a single resource, then the
+		// ID doesn't have a trailing index.
+		if cr.Count == 1 {
+			id = v.ResourceId()
+		}
+
 		r, ok := c.state.Resources[id]
 		if !ok {
 			continue
diff --git a/terraform/context_test.go b/terraform/context_test.go
index 1c658d4f28e1..2557273edd12 100644
--- a/terraform/context_test.go
+++ b/terraform/context_test.go
@@ -1781,6 +1781,29 @@ func TestContextPlan_taint(t *testing.T) {
 	}
 }
 
+func TestContextPlan_varMultiCountOne(t *testing.T) {
+	c := testConfig(t, "plan-var-multi-count-one")
+	p := testProvider("aws")
+	p.DiffFn = testDiffFn
+	ctx := testContext(t, &ContextOpts{
+		Config: c,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+	})
+
+	plan, err := ctx.Plan(nil)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	actual := strings.TrimSpace(plan.String())
+	expected := strings.TrimSpace(testTerraformPlanVarMultiCountOneStr)
+	if actual != expected {
+		t.Fatalf("bad:\n%s", actual)
+	}
+}
+
 func TestContextRefresh(t *testing.T) {
 	p := testProvider("aws")
 	c := testConfig(t, "refresh-basic")
diff --git a/terraform/terraform_test.go b/terraform/terraform_test.go
index b852864cf09e..a952f18e2f75 100644
--- a/terraform/terraform_test.go
+++ b/terraform/terraform_test.go
@@ -478,3 +478,19 @@ aws_instance.foo:
   ID = bar
   num = 2
 `
+
+const testTerraformPlanVarMultiCountOneStr = `
+DIFF:
+
+CREATE: aws_instance.bar
+  foo:  "" => "2"
+  type: "" => "aws_instance"
+CREATE: aws_instance.foo
+  num:  "" => "2"
+  type: "" => "aws_instance"
+
+STATE:
+
+<no state>
+`
+
diff --git a/terraform/test-fixtures/plan-var-multi-count-one/main.tf b/terraform/test-fixtures/plan-var-multi-count-one/main.tf
new file mode 100644
index 000000000000..6fd84932f105
--- /dev/null
+++ b/terraform/test-fixtures/plan-var-multi-count-one/main.tf
@@ -0,0 +1,9 @@
+resource "aws_instance" "foo" {
+    num = "2"
+
+    count = 1
+}
+
+resource "aws_instance" "bar" {
+    foo = "${aws_instance.foo.*.num}"
+}