Add test attempting to reproduce #2598

This attempts to reproduce the issue described in #2598 whereby outputs
added after an apply are not reflected in the output. As per the issue
the outputs are described using the JSON syntax.

terraform/context_apply_test.go

@@ -2851,6 +2851,55 @@ func TestContext2Apply_outputInvalid(t *testing.T) {
 	}
 }
 
+func TestContext2Apply_outputAdd(t *testing.T) {
+	m1 := testModule(t, "apply-output-add-before")
+	p1 := testProvider("aws")
+	p1.ApplyFn = testApplyFn
+	p1.DiffFn = testDiffFn
+	ctx1 := testContext2(t, &ContextOpts{
+		Module: m1,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p1),
+		},
+	})
+
+	if _, err := ctx1.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	state1, err := ctx1.Apply()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	m2 := testModule(t, "apply-output-add-after")
+	p2 := testProvider("aws")
+	p2.ApplyFn = testApplyFn
+	p2.DiffFn = testDiffFn
+	ctx2 := testContext2(t, &ContextOpts{
+		Module: m2,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p2),
+		},
+		State: state1,
+	})
+
+	if _, err := ctx2.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	state2, err := ctx2.Apply()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	actual := strings.TrimSpace(state2.String())
+	expected := strings.TrimSpace(testTerraformApplyOutputAddStr)
+	if actual != expected {
+		t.Fatalf("bad: \n%s", actual)
+	}
+}
+
 func TestContext2Apply_outputList(t *testing.T) {
 	m := testModule(t, "apply-output-list")
 	p := testProvider("aws")

terraform/terraform_test.go

@@ -575,6 +575,22 @@ Outputs:
 foo_num = 2
 `
 
+const testTerraformApplyOutputAddStr = `
+aws_instance.test.0:
+  ID = foo
+  foo = foo0
+  type = aws_instance
+aws_instance.test.1:
+  ID = foo
+  foo = foo1
+  type = aws_instance
+
+Outputs:
+
+firstOutput = foo0
+secondOutput = foo1
+`
+
 const testTerraformApplyOutputListStr = `
 aws_instance.bar.0:
   ID = foo

terraform/test-fixtures/apply-output-add-after/main.tf

@@ -0,0 +1,6 @@
+provider "aws" {}
+
+resource "aws_instance" "test" {
+		foo = "${format("foo%d", count.index)}"
+		count = 2
+}

terraform/test-fixtures/apply-output-add-after/outputs.tf.json

@@ -0,0 +1,10 @@
+{
+		"output": {
+				"firstOutput": {
+						"value": "${aws_instance.test.0.foo}"
+				},
+				"secondOutput": {
+						"value": "${aws_instance.test.1.foo}"
+				}
+		}
+}

terraform/test-fixtures/apply-output-add-before/main.tf

@@ -0,0 +1,6 @@
+provider "aws" {}
+
+resource "aws_instance" "test" {
+		foo = "${format("foo%d", count.index)}"
+		count = 2
+}

terraform/test-fixtures/apply-output-add-before/outputs.tf.json

@@ -0,0 +1,7 @@
+{
+		"output": {
+				"firstOutput": {
+						"value": "${aws_instance.test.0.foo}"
+				}
+		}
+}