terraform: tests for increasing count from 1 to > 1

terraform/context_test.go

@@ -668,7 +668,7 @@ func TestContextPlan_count(t *testing.T) {
 	}
 }
 
-func TestContextPlan_countDecrease(t *testing.T) {
+func TestContextPlan_countDecreaseToOne(t *testing.T) {
 	c := testConfig(t, "plan-count-dec")
 	p := testProvider("aws")
 	p.DiffFn = testDiffFn
@@ -712,6 +712,42 @@ func TestContextPlan_countDecrease(t *testing.T) {
 	}
 }
 
+func TestContextPlan_countIncreaseFromOne(t *testing.T) {
+	c := testConfig(t, "plan-count-inc")
+	p := testProvider("aws")
+	p.DiffFn = testDiffFn
+	s := &State{
+		Resources: map[string]*ResourceState{
+			"aws_instance.foo": &ResourceState{
+				ID:   "bar",
+				Type: "aws_instance",
+				Attributes: map[string]string{
+					"foo":  "foo",
+					"type": "aws_instance",
+				},
+			},
+		},
+	}
+	ctx := testContext(t, &ContextOpts{
+		Config: c,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+		State: s,
+	})
+
+	plan, err := ctx.Plan(nil)
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	actual := strings.TrimSpace(plan.String())
+	expected := strings.TrimSpace(testTerraformPlanCountIncreaseStr)
+	if actual != expected {
+		t.Fatalf("bad:\n%s", actual)
+	}
+}
+
 func TestContextPlan_destroy(t *testing.T) {
 	c := testConfig(t, "plan-destroy")
 	p := testProvider("aws")

terraform/graph.go

@@ -172,10 +172,18 @@ func graphAddConfigResources(
 			if s != nil {
 				state = s.Resources[name]
 
-				// If the count is one, check the state for ".0" appended, which
-				// might exist if we go from count > 1 to count == 1.
-				if state == nil && r.Count == 1 {
+				if state == nil {
+					if r.Count == 1 {
+						// If the count is one, check the state for ".0"
+						// appended, which might exist if we go from
+						// count > 1 to count == 1.
 						state = s.Resources[r.Id()+".0"]
+					} else if i == 0 {
+						// If count is greater than one, check for state
+						// with just the ID, which might exist if we go
+						// from count == 1 to count > 1
+						state = s.Resources[r.Id()]
+					}
 				}
 			}
 			if state == nil {

terraform/terraform_test.go

@@ -203,6 +203,27 @@ aws_instance.foo.2:
   ID = bar
 `
 
+const testTerraformPlanCountIncreaseStr = `
+DIFF:
+
+UPDATE: aws_instance.bar
+  foo:  "" => "bar"
+  type: "" => "aws_instance"
+UPDATE: aws_instance.foo.1
+  foo:  "" => "foo"
+  type: "" => "aws_instance"
+UPDATE: aws_instance.foo.2
+  foo:  "" => "foo"
+  type: "" => "aws_instance"
+
+STATE:
+
+aws_instance.foo:
+  ID = bar
+  foo = foo
+  type = aws_instance
+`
+
 const testTerraformPlanDestroyStr = `
 DIFF:
 

terraform/test-fixtures/plan-count-inc/main.tf

@@ -0,0 +1,8 @@
+resource "aws_instance" "foo" {
+    foo = "foo"
+    count = 3
+}
+
+resource "aws_instance" "bar" {
+    foo = "bar"
+}