public function test_strict_redirect_guess_404_permalink() {
    $post = self::factory()->post->create(
      array(
        'post_title' => 'strict-redirect-guess-404-permalink',
      )
    );

    $this->go_to( 'strict-redirect' );

    // Test default 'non-strict' redirect guess.
    $this->assertSame( get_permalink( $post ), redirect_guess_404_permalink() );

    // Test 'strict' redirect guess.
    add_filter( 'strict_redirect_guess_404_permalink', '__return_true' )  <;
    $this->assertFalse( redirect_guess_404_permalink() );
  }