ResolvedCSSStyleDeclaration.cpp 24 KB

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  1. /*
  2. * Copyright (c) 2021-2022, Andreas Kling <kling@serenityos.org>
  3. * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
  4. *
  5. * SPDX-License-Identifier: BSD-2-Clause
  6. */
  7. #include <AK/Debug.h>
  8. #include <AK/NonnullRefPtr.h>
  9. #include <LibWeb/CSS/Enums.h>
  10. #include <LibWeb/CSS/ResolvedCSSStyleDeclaration.h>
  11. #include <LibWeb/CSS/StyleComputer.h>
  12. #include <LibWeb/DOM/Document.h>
  13. #include <LibWeb/DOM/Element.h>
  14. namespace Web::CSS {
  15. ResolvedCSSStyleDeclaration::ResolvedCSSStyleDeclaration(DOM::Element& element)
  16. : m_element(element)
  17. {
  18. }
  19. size_t ResolvedCSSStyleDeclaration::length() const
  20. {
  21. return 0;
  22. }
  23. String ResolvedCSSStyleDeclaration::item(size_t index) const
  24. {
  25. (void)index;
  26. return {};
  27. }
  28. static RefPtr<StyleValue> style_value_for_display(CSS::Display display)
  29. {
  30. if (display.is_none())
  31. return IdentifierStyleValue::create(CSS::ValueID::None);
  32. if (display.is_outside_and_inside()) {
  33. NonnullRefPtrVector<StyleValue> values;
  34. switch (display.outside()) {
  35. case CSS::Display::Outside::Inline:
  36. values.append(IdentifierStyleValue::create(CSS::ValueID::Inline));
  37. break;
  38. case CSS::Display::Outside::Block:
  39. values.append(IdentifierStyleValue::create(CSS::ValueID::Block));
  40. break;
  41. case CSS::Display::Outside::RunIn:
  42. values.append(IdentifierStyleValue::create(CSS::ValueID::RunIn));
  43. break;
  44. }
  45. switch (display.inside()) {
  46. case CSS::Display::Inside::Flow:
  47. values.append(IdentifierStyleValue::create(CSS::ValueID::Flow));
  48. break;
  49. case CSS::Display::Inside::FlowRoot:
  50. values.append(IdentifierStyleValue::create(CSS::ValueID::FlowRoot));
  51. break;
  52. case CSS::Display::Inside::Table:
  53. values.append(IdentifierStyleValue::create(CSS::ValueID::Table));
  54. break;
  55. case CSS::Display::Inside::Flex:
  56. values.append(IdentifierStyleValue::create(CSS::ValueID::Flex));
  57. break;
  58. case CSS::Display::Inside::Grid:
  59. values.append(IdentifierStyleValue::create(CSS::ValueID::Grid));
  60. break;
  61. case CSS::Display::Inside::Ruby:
  62. values.append(IdentifierStyleValue::create(CSS::ValueID::Ruby));
  63. break;
  64. }
  65. return StyleValueList::create(move(values), StyleValueList::Separator::Space);
  66. }
  67. if (display.is_internal()) {
  68. switch (display.internal()) {
  69. case CSS::Display::Internal::TableRowGroup:
  70. return IdentifierStyleValue::create(CSS::ValueID::TableRowGroup);
  71. case CSS::Display::Internal::TableHeaderGroup:
  72. return IdentifierStyleValue::create(CSS::ValueID::TableHeaderGroup);
  73. case CSS::Display::Internal::TableFooterGroup:
  74. return IdentifierStyleValue::create(CSS::ValueID::TableFooterGroup);
  75. case CSS::Display::Internal::TableRow:
  76. return IdentifierStyleValue::create(CSS::ValueID::TableRow);
  77. case CSS::Display::Internal::TableCell:
  78. return IdentifierStyleValue::create(CSS::ValueID::TableCell);
  79. case CSS::Display::Internal::TableColumnGroup:
  80. return IdentifierStyleValue::create(CSS::ValueID::TableColumnGroup);
  81. case CSS::Display::Internal::TableColumn:
  82. return IdentifierStyleValue::create(CSS::ValueID::TableColumn);
  83. case CSS::Display::Internal::TableCaption:
  84. return IdentifierStyleValue::create(CSS::ValueID::TableCaption);
  85. case CSS::Display::Internal::RubyBase:
  86. return IdentifierStyleValue::create(CSS::ValueID::RubyBase);
  87. case CSS::Display::Internal::RubyText:
  88. return IdentifierStyleValue::create(CSS::ValueID::RubyText);
  89. case CSS::Display::Internal::RubyBaseContainer:
  90. return IdentifierStyleValue::create(CSS::ValueID::RubyBaseContainer);
  91. case CSS::Display::Internal::RubyTextContainer:
  92. return IdentifierStyleValue::create(CSS::ValueID::RubyTextContainer);
  93. }
  94. }
  95. TODO();
  96. }
  97. static NonnullRefPtr<StyleValue> value_or_default(Optional<StyleProperty> property, NonnullRefPtr<StyleValue> default_style)
  98. {
  99. if (property.has_value())
  100. return property.value().value;
  101. return default_style;
  102. }
  103. static NonnullRefPtr<StyleValue> style_value_for_length_percentage(LengthPercentage const& length_percentage)
  104. {
  105. if (length_percentage.is_percentage())
  106. return PercentageStyleValue::create(length_percentage.percentage());
  107. if (length_percentage.is_length())
  108. return LengthStyleValue::create(length_percentage.length());
  109. return length_percentage.calculated();
  110. }
  111. RefPtr<StyleValue> ResolvedCSSStyleDeclaration::style_value_for_property(Layout::NodeWithStyle const& layout_node, PropertyID property_id) const
  112. {
  113. switch (property_id) {
  114. case CSS::PropertyID::Float:
  115. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().float_()));
  116. case CSS::PropertyID::Clear:
  117. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().clear()));
  118. case CSS::PropertyID::Cursor:
  119. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().cursor()));
  120. case CSS::PropertyID::Display:
  121. return style_value_for_display(layout_node.computed_values().display());
  122. case CSS::PropertyID::ZIndex: {
  123. auto maybe_z_index = layout_node.computed_values().z_index();
  124. if (!maybe_z_index.has_value())
  125. return {};
  126. return NumericStyleValue::create_integer(maybe_z_index.release_value());
  127. }
  128. case CSS::PropertyID::TextAlign:
  129. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().text_align()));
  130. case CSS::PropertyID::TextDecorationLine:
  131. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().text_decoration_line()));
  132. case CSS::PropertyID::TextDecorationStyle:
  133. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().text_decoration_style()));
  134. case CSS::PropertyID::TextTransform:
  135. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().text_transform()));
  136. case CSS::PropertyID::Position:
  137. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().position()));
  138. case CSS::PropertyID::WhiteSpace:
  139. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().white_space()));
  140. case CSS::PropertyID::FlexDirection:
  141. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().flex_direction()));
  142. case CSS::PropertyID::FlexWrap:
  143. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().flex_wrap()));
  144. case CSS::PropertyID::FlexBasis: {
  145. switch (layout_node.computed_values().flex_basis().type) {
  146. case FlexBasis::Content:
  147. return IdentifierStyleValue::create(CSS::ValueID::Content);
  148. case FlexBasis::LengthPercentage:
  149. return style_value_for_length_percentage(*layout_node.computed_values().flex_basis().length_percentage);
  150. case FlexBasis::Auto:
  151. return IdentifierStyleValue::create(CSS::ValueID::Auto);
  152. default:
  153. VERIFY_NOT_REACHED();
  154. }
  155. break;
  156. case CSS::PropertyID::FlexGrow:
  157. return NumericStyleValue::create_float(layout_node.computed_values().flex_grow());
  158. case CSS::PropertyID::FlexShrink:
  159. return NumericStyleValue::create_float(layout_node.computed_values().flex_shrink());
  160. case CSS::PropertyID::Order:
  161. return NumericStyleValue::create_integer(layout_node.computed_values().order());
  162. case CSS::PropertyID::Opacity:
  163. return NumericStyleValue::create_float(layout_node.computed_values().opacity());
  164. case CSS::PropertyID::ImageRendering:
  165. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().image_rendering()));
  166. case CSS::PropertyID::JustifyContent:
  167. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().justify_content()));
  168. case CSS::PropertyID::BoxShadow: {
  169. auto box_shadow_layers = layout_node.computed_values().box_shadow();
  170. if (box_shadow_layers.is_empty())
  171. return {};
  172. auto make_box_shadow_style_value = [](ShadowData const& data) {
  173. return ShadowStyleValue::create(data.color, data.offset_x, data.offset_y, data.blur_radius, data.spread_distance, data.placement);
  174. };
  175. if (box_shadow_layers.size() == 1)
  176. return make_box_shadow_style_value(box_shadow_layers.first());
  177. NonnullRefPtrVector<StyleValue> box_shadow;
  178. box_shadow.ensure_capacity(box_shadow_layers.size());
  179. for (auto const& layer : box_shadow_layers)
  180. box_shadow.append(make_box_shadow_style_value(layer));
  181. return StyleValueList::create(move(box_shadow), StyleValueList::Separator::Comma);
  182. }
  183. case CSS::PropertyID::Width:
  184. return style_value_for_length_percentage(layout_node.computed_values().width().value_or(Length::make_auto()));
  185. case CSS::PropertyID::MinWidth:
  186. if (!layout_node.computed_values().min_width().has_value())
  187. return IdentifierStyleValue::create(CSS::ValueID::Auto);
  188. return style_value_for_length_percentage(layout_node.computed_values().min_width().value());
  189. case CSS::PropertyID::MaxWidth:
  190. if (!layout_node.computed_values().max_width().has_value())
  191. return IdentifierStyleValue::create(CSS::ValueID::None);
  192. return style_value_for_length_percentage(layout_node.computed_values().max_width().value());
  193. case CSS::PropertyID::Height:
  194. return style_value_for_length_percentage(layout_node.computed_values().height().value_or(Length::make_auto()));
  195. case CSS::PropertyID::MinHeight:
  196. if (!layout_node.computed_values().min_height().has_value())
  197. return IdentifierStyleValue::create(CSS::ValueID::Auto);
  198. return style_value_for_length_percentage(layout_node.computed_values().min_height().value());
  199. case CSS::PropertyID::MaxHeight:
  200. if (!layout_node.computed_values().max_height().has_value())
  201. return IdentifierStyleValue::create(CSS::ValueID::None);
  202. return style_value_for_length_percentage(layout_node.computed_values().max_height().value());
  203. case CSS::PropertyID::Margin: {
  204. auto margin = layout_node.computed_values().margin();
  205. auto values = NonnullRefPtrVector<StyleValue> {};
  206. values.append(style_value_for_length_percentage(margin.top));
  207. values.append(style_value_for_length_percentage(margin.right));
  208. values.append(style_value_for_length_percentage(margin.bottom));
  209. values.append(style_value_for_length_percentage(margin.left));
  210. return StyleValueList::create(move(values), StyleValueList::Separator::Space);
  211. }
  212. case CSS::PropertyID::MarginTop:
  213. return style_value_for_length_percentage(layout_node.computed_values().margin().top);
  214. case CSS::PropertyID::MarginRight:
  215. return style_value_for_length_percentage(layout_node.computed_values().margin().right);
  216. case CSS::PropertyID::MarginBottom:
  217. return style_value_for_length_percentage(layout_node.computed_values().margin().bottom);
  218. case CSS::PropertyID::MarginLeft:
  219. return style_value_for_length_percentage(layout_node.computed_values().margin().left);
  220. case CSS::PropertyID::Padding: {
  221. auto padding = layout_node.computed_values().padding();
  222. auto values = NonnullRefPtrVector<StyleValue> {};
  223. values.append(style_value_for_length_percentage(padding.top));
  224. values.append(style_value_for_length_percentage(padding.right));
  225. values.append(style_value_for_length_percentage(padding.bottom));
  226. values.append(style_value_for_length_percentage(padding.left));
  227. return StyleValueList::create(move(values), StyleValueList::Separator::Space);
  228. }
  229. case CSS::PropertyID::PaddingTop:
  230. return style_value_for_length_percentage(layout_node.computed_values().padding().top);
  231. case CSS::PropertyID::PaddingRight:
  232. return style_value_for_length_percentage(layout_node.computed_values().padding().right);
  233. case CSS::PropertyID::PaddingBottom:
  234. return style_value_for_length_percentage(layout_node.computed_values().padding().bottom);
  235. case CSS::PropertyID::PaddingLeft:
  236. return style_value_for_length_percentage(layout_node.computed_values().padding().left);
  237. case CSS::PropertyID::BorderRadius: {
  238. auto maybe_top_left_radius = property(CSS::PropertyID::BorderTopLeftRadius);
  239. auto maybe_top_right_radius = property(CSS::PropertyID::BorderTopRightRadius);
  240. auto maybe_bottom_left_radius = property(CSS::PropertyID::BorderBottomLeftRadius);
  241. auto maybe_bottom_right_radius = property(CSS::PropertyID::BorderBottomRightRadius);
  242. RefPtr<BorderRadiusStyleValue> top_left_radius, top_right_radius, bottom_left_radius, bottom_right_radius;
  243. if (maybe_top_left_radius.has_value()) {
  244. VERIFY(maybe_top_left_radius.value().value->is_border_radius());
  245. top_left_radius = maybe_top_left_radius.value().value->as_border_radius();
  246. }
  247. if (maybe_top_right_radius.has_value()) {
  248. VERIFY(maybe_top_right_radius.value().value->is_border_radius());
  249. top_right_radius = maybe_top_right_radius.value().value->as_border_radius();
  250. }
  251. if (maybe_bottom_left_radius.has_value()) {
  252. VERIFY(maybe_bottom_left_radius.value().value->is_border_radius());
  253. bottom_left_radius = maybe_bottom_left_radius.value().value->as_border_radius();
  254. }
  255. if (maybe_bottom_right_radius.has_value()) {
  256. VERIFY(maybe_bottom_right_radius.value().value->is_border_radius());
  257. bottom_right_radius = maybe_bottom_right_radius.value().value->as_border_radius();
  258. }
  259. return CombinedBorderRadiusStyleValue::create(top_left_radius.release_nonnull(), top_right_radius.release_nonnull(), bottom_right_radius.release_nonnull(), bottom_left_radius.release_nonnull());
  260. }
  261. // FIXME: The two radius components are not yet stored, as we currently don't actually render them.
  262. case CSS::PropertyID::BorderBottomLeftRadius:
  263. return BorderRadiusStyleValue::create(layout_node.computed_values().border_bottom_left_radius(), layout_node.computed_values().border_bottom_left_radius());
  264. case CSS::PropertyID::BorderBottomRightRadius:
  265. return BorderRadiusStyleValue::create(layout_node.computed_values().border_bottom_right_radius(), layout_node.computed_values().border_bottom_right_radius());
  266. case CSS::PropertyID::BorderTopLeftRadius:
  267. return BorderRadiusStyleValue::create(layout_node.computed_values().border_top_left_radius(), layout_node.computed_values().border_top_left_radius());
  268. case CSS::PropertyID::BorderTopRightRadius:
  269. return BorderRadiusStyleValue::create(layout_node.computed_values().border_top_right_radius(), layout_node.computed_values().border_top_right_radius());
  270. case CSS::PropertyID::BorderTopWidth:
  271. return LengthStyleValue::create(Length::make_px(layout_node.computed_values().border_top().width));
  272. case CSS::PropertyID::BorderRightWidth:
  273. return LengthStyleValue::create(Length::make_px(layout_node.computed_values().border_right().width));
  274. case CSS::PropertyID::BorderBottomWidth:
  275. return LengthStyleValue::create(Length::make_px(layout_node.computed_values().border_bottom().width));
  276. case CSS::PropertyID::BorderLeftWidth:
  277. return LengthStyleValue::create(Length::make_px(layout_node.computed_values().border_left().width));
  278. case CSS::PropertyID::BorderTopColor:
  279. return ColorStyleValue::create(layout_node.computed_values().border_top().color);
  280. case CSS::PropertyID::BorderRightColor:
  281. return ColorStyleValue::create(layout_node.computed_values().border_right().color);
  282. case CSS::PropertyID::BorderBottomColor:
  283. return ColorStyleValue::create(layout_node.computed_values().border_bottom().color);
  284. case CSS::PropertyID::BorderLeftColor:
  285. return ColorStyleValue::create(layout_node.computed_values().border_left().color);
  286. case CSS::PropertyID::BorderTopStyle:
  287. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().border_top().line_style));
  288. case CSS::PropertyID::BorderRightStyle:
  289. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().border_right().line_style));
  290. case CSS::PropertyID::BorderBottomStyle:
  291. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().border_bottom().line_style));
  292. case CSS::PropertyID::BorderLeftStyle:
  293. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().border_left().line_style));
  294. case CSS::PropertyID::BorderTop: {
  295. auto border = layout_node.computed_values().border_top();
  296. auto width = LengthStyleValue::create(Length::make_px(border.width));
  297. auto style = IdentifierStyleValue::create(to_value_id(border.line_style));
  298. auto color = ColorStyleValue::create(border.color);
  299. return BorderStyleValue::create(width, style, color);
  300. }
  301. case CSS::PropertyID::BorderRight: {
  302. auto border = layout_node.computed_values().border_right();
  303. auto width = LengthStyleValue::create(Length::make_px(border.width));
  304. auto style = IdentifierStyleValue::create(to_value_id(border.line_style));
  305. auto color = ColorStyleValue::create(border.color);
  306. return BorderStyleValue::create(width, style, color);
  307. }
  308. case CSS::PropertyID::BorderBottom: {
  309. auto border = layout_node.computed_values().border_bottom();
  310. auto width = LengthStyleValue::create(Length::make_px(border.width));
  311. auto style = IdentifierStyleValue::create(to_value_id(border.line_style));
  312. auto color = ColorStyleValue::create(border.color);
  313. return BorderStyleValue::create(width, style, color);
  314. }
  315. case CSS::PropertyID::BorderLeft: {
  316. auto border = layout_node.computed_values().border_left();
  317. auto width = LengthStyleValue::create(Length::make_px(border.width));
  318. auto style = IdentifierStyleValue::create(to_value_id(border.line_style));
  319. auto color = ColorStyleValue::create(border.color);
  320. return BorderStyleValue::create(width, style, color);
  321. }
  322. case CSS::PropertyID::OverflowX:
  323. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().overflow_x()));
  324. case CSS::PropertyID::OverflowY:
  325. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().overflow_y()));
  326. case CSS::PropertyID::Color:
  327. return ColorStyleValue::create(layout_node.computed_values().color());
  328. case PropertyID::BackgroundColor:
  329. return ColorStyleValue::create(layout_node.computed_values().background_color());
  330. case CSS::PropertyID::Background: {
  331. auto maybe_background_color = property(CSS::PropertyID::BackgroundColor);
  332. auto maybe_background_image = property(CSS::PropertyID::BackgroundImage);
  333. auto maybe_background_position = property(CSS::PropertyID::BackgroundPosition);
  334. auto maybe_background_size = property(CSS::PropertyID::BackgroundSize);
  335. auto maybe_background_repeat = property(CSS::PropertyID::BackgroundRepeat);
  336. auto maybe_background_attachment = property(CSS::PropertyID::BackgroundAttachment);
  337. auto maybe_background_origin = property(CSS::PropertyID::BackgroundOrigin);
  338. auto maybe_background_clip = property(CSS::PropertyID::BackgroundClip);
  339. return BackgroundStyleValue::create(
  340. value_or_default(maybe_background_color, InitialStyleValue::the()),
  341. value_or_default(maybe_background_image, IdentifierStyleValue::create(CSS::ValueID::None)),
  342. value_or_default(maybe_background_position, PositionStyleValue::create(PositionEdge::Left, Length::make_px(0), PositionEdge::Top, Length::make_px(0))),
  343. value_or_default(maybe_background_size, IdentifierStyleValue::create(CSS::ValueID::Auto)),
  344. value_or_default(maybe_background_repeat, BackgroundRepeatStyleValue::create(CSS::Repeat::Repeat, CSS::Repeat::Repeat)),
  345. value_or_default(maybe_background_attachment, IdentifierStyleValue::create(CSS::ValueID::Scroll)),
  346. value_or_default(maybe_background_origin, IdentifierStyleValue::create(CSS::ValueID::PaddingBox)),
  347. value_or_default(maybe_background_clip, IdentifierStyleValue::create(CSS::ValueID::BorderBox)));
  348. }
  349. case CSS::PropertyID::VerticalAlign:
  350. if (auto const* length_percentage = layout_node.computed_values().vertical_align().get_pointer<CSS::LengthPercentage>()) {
  351. if (length_percentage->is_length())
  352. return LengthStyleValue::create(length_percentage->length());
  353. if (length_percentage->is_percentage())
  354. return PercentageStyleValue::create(length_percentage->percentage());
  355. VERIFY_NOT_REACHED();
  356. }
  357. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().vertical_align().get<CSS::VerticalAlign>()));
  358. case CSS::PropertyID::ListStyleType:
  359. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().list_style_type()));
  360. case CSS::PropertyID::BoxSizing:
  361. return IdentifierStyleValue::create(to_value_id(layout_node.computed_values().box_sizing()));
  362. case CSS::PropertyID::Invalid:
  363. return IdentifierStyleValue::create(CSS::ValueID::Invalid);
  364. case CSS::PropertyID::Custom:
  365. dbgln_if(LIBWEB_CSS_DEBUG, "Computed style for custom properties was requested (?)");
  366. return {};
  367. default:
  368. dbgln_if(LIBWEB_CSS_DEBUG, "FIXME: Computed style for the '{}' property was requested", string_from_property_id(property_id));
  369. return {};
  370. }
  371. }
  372. }
  373. Optional<StyleProperty> ResolvedCSSStyleDeclaration::property(PropertyID property_id) const
  374. {
  375. if (CSS::property_affects_layout(property_id)) {
  376. const_cast<DOM::Document&>(m_element->document()).update_layout();
  377. } else {
  378. // FIXME: If we had a way to update style for a single element, this would be a good place to use it.
  379. const_cast<DOM::Document&>(m_element->document()).update_style();
  380. }
  381. if (!m_element->layout_node()) {
  382. auto style = m_element->document().style_computer().compute_style(const_cast<DOM::Element&>(*m_element));
  383. if (auto maybe_property = style->property(property_id); maybe_property.has_value()) {
  384. return StyleProperty {
  385. .property_id = property_id,
  386. .value = maybe_property.release_value(),
  387. };
  388. }
  389. return {};
  390. }
  391. auto& layout_node = *m_element->layout_node();
  392. auto value = style_value_for_property(layout_node, property_id);
  393. if (!value)
  394. return {};
  395. return StyleProperty {
  396. .property_id = property_id,
  397. .value = value.release_nonnull(),
  398. };
  399. }
  400. // https://drafts.csswg.org/cssom/#dom-cssstyledeclaration-setproperty
  401. DOM::ExceptionOr<void> ResolvedCSSStyleDeclaration::set_property(PropertyID, StringView, StringView)
  402. {
  403. // 1. If the computed flag is set, then throw a NoModificationAllowedError exception.
  404. return DOM::NoModificationAllowedError::create("Cannot modify properties in result of getComputedStyle()");
  405. }
  406. // https://drafts.csswg.org/cssom/#dom-cssstyledeclaration-removeproperty
  407. DOM::ExceptionOr<String> ResolvedCSSStyleDeclaration::remove_property(PropertyID)
  408. {
  409. // 1. If the computed flag is set, then throw a NoModificationAllowedError exception.
  410. return DOM::NoModificationAllowedError::create("Cannot remove properties from result of getComputedStyle()");
  411. }
  412. String ResolvedCSSStyleDeclaration::serialized() const
  413. {
  414. // https://www.w3.org/TR/cssom/#dom-cssstyledeclaration-csstext
  415. // If the computed flag is set, then return the empty string.
  416. // NOTE: ResolvedCSSStyleDeclaration is something you would only get from window.getComputedStyle(),
  417. // which returns what the spec calls "resolved style". The "computed flag" is always set here.
  418. return String::empty();
  419. }
  420. }