core: test coverage around map key regression

tests to cover the HCL-level issue fixed in
https://github.com/hashicorp/hcl/pull/65

command/flag_kv_test.go

@@ -35,6 +35,12 @@ func TestFlagKV(t *testing.T) {
 			false,
 		},
 
+		{
+			"map.key=foo",
+			map[string]string{"map.key": "foo"},
+			false,
+		},
+
 		{
 			"key",
 			nil,
@@ -84,6 +90,12 @@ foo = "bar"
 			map[string]string{"foo": "bar"},
 			false,
 		},
+
+		{
+			`map.key = "foo"`,
+			map[string]string{"map.key": "foo"},
+			false,
+		},
 	}
 
 	path := testTempFile(t)
@@ -96,7 +108,7 @@ foo = "bar"
 		f := new(FlagKVFile)
 		err := f.Set(path)
 		if err != nil != tc.Error {
-			t.Fatalf("bad error. Input: %#v", tc.Input)
+			t.Fatalf("bad error. Input: %#v, err: %s", tc.Input, err)
 		}
 
 		actual := map[string]string(*f)

terraform/context_apply_test.go

@@ -807,6 +807,46 @@ func TestContext2Apply_countVariable(t *testing.T) {
 	}
 }
 
+func TestContext2Apply_mapVariableOverride(t *testing.T) {
+	m := testModule(t, "apply-map-var-override")
+	p := testProvider("aws")
+	p.ApplyFn = testApplyFn
+	p.DiffFn = testDiffFn
+	ctx := testContext2(t, &ContextOpts{
+		Module: m,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+		Variables: map[string]string{
+			"images.us-west-2": "overridden",
+		},
+	})
+
+	if _, err := ctx.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	state, err := ctx.Apply()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	actual := strings.TrimSpace(state.String())
+	expected := strings.TrimSpace(`
+aws_instance.bar:
+  ID = foo
+  ami = overridden
+  type = aws_instance
+aws_instance.foo:
+  ID = foo
+  ami = image-1234
+  type = aws_instance
+	`)
+	if actual != expected {
+		t.Fatalf("got: \n%s\nexpected: \n%s", actual, expected)
+	}
+}
+
 func TestContext2Apply_module(t *testing.T) {
 	m := testModule(t, "apply-module")
 	p := testProvider("aws")

terraform/test-fixtures/apply-map-var-override/main.tf

@@ -0,0 +1,14 @@
+variable "images" {
+    default = {
+        us-east-1 = "image-1234"
+        us-west-2 = "image-4567"
+    }
+}
+
+resource "aws_instance" "foo" {
+    ami = "${lookup(var.images, "us-east-1")}"
+}
+
+resource "aws_instance" "bar" {
+    ami = "${lookup(var.images, "us-west-2")}"
+}