Use pre-apply state when destroying.

We want to use the pre-apply state when destroying for checks when
TestStep.Destroy is true, because the state after is going to be empty.
This preserves the behavior of v1 and before, which providers may be
relying on.

Author: paddycarver

helper/resource/testing_new_config.go

@@ -98,8 +98,14 @@ func testStepNewConfig(t testing.T, c TestCase, wd *tftest.WorkingDir, step Test
 		// Run any configured checks
 		if step.Check != nil {
 			state.IsBinaryDrivenTest = true
-			if err := step.Check(state); err != nil {
-				return err
+			if step.Destroy {
+				if err := step.Check(stateBeforeApplication); err != nil {
+					return fmt.Errorf("Check failed: %w", err)
+				}
+			} else {
+				if err := step.Check(state); err != nil {
+					return fmt.Errorf("Check failed: %w", err)
+				}
 			}
 		}
 	}