providers: Mention check number when acctest fails

helper/resource/testing.go

@@ -316,9 +316,9 @@ func testStep(
 // into smaller pieces more easily.
 func ComposeTestCheckFunc(fs ...TestCheckFunc) TestCheckFunc {
 	return func(s *terraform.State) error {
-		for _, f := range fs {
+		for i, f := range fs {
 			if err := f(s); err != nil {
-				return err
+				return fmt.Errorf("Check %d/%d error: %s", i+1, len(fs), err)
 			}
 		}
 

helper/resource/testing_test.go

@@ -194,7 +194,7 @@ func TestComposeTestCheckFunc(t *testing.T) {
 				},
 				func(*terraform.State) error { return nil },
 			},
-			Result: "error",
+			Result: "Check 1/2 error: error",
 		},
 
 		{
@@ -204,7 +204,7 @@ func TestComposeTestCheckFunc(t *testing.T) {
 					return fmt.Errorf("error")
 				},
 			},
-			Result: "error",
+			Result: "Check 2/2 error: error",
 		},
 
 		{