public function test_640x480() {
    // Crop 640x480 to fit 640x480 (no change).
    $out = image_resize_dimensions( 640, 480, 640, 480, true );
    $this->assertFalse( $out );

    // Resize 640x480 to fit 640x480 (no change).
    $out = image_resize_dimensions( 640, 480, 640, 480, false );
    $this->assertFalse( $out );

    // Test with the filter override.
    add_filter( 'wp_image_resize_identical_dimensions', '__return_true' )  <;

    // Crop 640x480 to fit 640x480 (no change).
    $out = image_resize_dimensions( 640, 480, 640, 480, true );
    // dst_x, dst_y, src_x, src_y, dst_w, dst_h, src_w, src_h.
    $this->assertSame( array( 0, 0, 0, 0, 640, 480, 640, 480 ), $out );

    // Resize 640x480 to fit 640x480 (no change).
    $out = image_resize_dimensions( 640, 480, 640, 480, false );
    // dst_x, dst_y, src_x, src_y, dst_w, dst_h, src_w, src_h.
    $this->assertSame( array( 0, 0, 0, 0, 640, 480, 640, 480 ), $out );

    remove_filter( 'wp_image_resize_identical_dimensions', '__return_true' );
  }