Merge pull request #19950 from hashicorp/jbardin/resource-tests

Container checks in TestCheckFuncs

helper/resource/testing.go

@@ -971,7 +971,19 @@ func TestCheckModuleResourceAttr(mp []string, name string, key string, value str
 }
 
 func testCheckResourceAttr(is *terraform.InstanceState, name string, key string, value string) error {
+	// Empty containers may be elided from the state.
+	// If the intent here is to check for an empty container, allow the key to
+	// also be non-existent.
+	emptyCheck := false
+	if value == "0" && (strings.HasSuffix(key, ".#") || strings.HasSuffix(key, ".%")) {
+		emptyCheck = true
+	}
+
 	if v, ok := is.Attributes[key]; !ok || v != value {
+		if emptyCheck && !ok {
+			return nil
+		}
+
 		if !ok {
 			return fmt.Errorf("%s: Attribute '%s' not found", name, key)
 		}
@@ -1014,7 +1026,20 @@ func TestCheckModuleNoResourceAttr(mp []string, name string, key string) TestChe
 }
 
 func testCheckNoResourceAttr(is *terraform.InstanceState, name string, key string) error {
-	if _, ok := is.Attributes[key]; ok {
+	// Empty containers may sometimes be included in the state.
+	// If the intent here is to check for an empty container, allow the value to
+	// also be "0".
+	emptyCheck := false
+	if strings.HasSuffix(key, ".#") || strings.HasSuffix(key, ".%") {
+		emptyCheck = true
+	}
+
+	val, exists := is.Attributes[key]
+	if emptyCheck && val == "0" {
+		return nil
+	}
+
+	if exists {
 		return fmt.Errorf("%s: Attribute '%s' found when not expected", name, key)
 	}
 

helper/resource/testing_test.go

@@ -1113,3 +1113,65 @@ resource "test_instance" "foo" {}
 const testConfigStrProvider = `
 provider "test" {}
 `
+
+func TestCheckResourceAttr_empty(t *testing.T) {
+	s := terraform.NewState()
+	s.AddModuleState(&terraform.ModuleState{
+		Path: []string{"root"},
+		Resources: map[string]*terraform.ResourceState{
+			"test_resource": &terraform.ResourceState{
+				Primary: &terraform.InstanceState{
+					Attributes: map[string]string{
+						"empty_list.#": "0",
+						"empty_map.%":  "0",
+					},
+				},
+			},
+		},
+	})
+
+	for _, key := range []string{
+		"empty_list.#",
+		"empty_map.%",
+		"missing_list.#",
+		"missing_map.%",
+	} {
+		t.Run(key, func(t *testing.T) {
+			check := TestCheckResourceAttr("test_resource", key, "0")
+			if err := check(s); err != nil {
+				t.Fatal(err)
+			}
+		})
+	}
+}
+
+func TestCheckNoResourceAttr_empty(t *testing.T) {
+	s := terraform.NewState()
+	s.AddModuleState(&terraform.ModuleState{
+		Path: []string{"root"},
+		Resources: map[string]*terraform.ResourceState{
+			"test_resource": &terraform.ResourceState{
+				Primary: &terraform.InstanceState{
+					Attributes: map[string]string{
+						"empty_list.#": "0",
+						"empty_map.%":  "0",
+					},
+				},
+			},
+		},
+	})
+
+	for _, key := range []string{
+		"empty_list.#",
+		"empty_map.%",
+		"missing_list.#",
+		"missing_map.%",
+	} {
+		t.Run(key, func(t *testing.T) {
+			check := TestCheckNoResourceAttr("test_resource", key)
+			if err := check(s); err != nil {
+				t.Fatal(err)
+			}
+		})
+	}
+}