blob: c5dc4bfac3e335dcaa35381d11861af9860fdde9 [file] [log] [blame]
// Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
/// Tools for manipulating HTML during code generation of analyzer and analysis
/// server.
import 'package:html/dom.dart' as dom;
/// Make a deep copy of the given HTML nodes.
List<dom.Node> cloneHtmlNodes(List<dom.Node> nodes) => node) => node.clone(true)).toList();
/// Return true if the given iterable contains only whitespace text nodes.
bool containsOnlyWhitespace(Iterable<dom.Node> nodes) {
for (var node in nodes) {
if (!isWhitespaceNode(node)) {
return false;
return true;
/// Get the text contents of the element, ignoring all markup.
String innerText(dom.Element parent) {
var buffer = StringBuffer();
void recurse(dom.Element parent) {
for (var child in parent.nodes) {
if (child is dom.Text) {
} else if (child is dom.Element) {
return buffer.toString();
/// Return true if the given node is a text node containing only whitespace, or
/// a comment.
bool isWhitespaceNode(dom.Node node) {
if (node is dom.Element) {
return false;
} else if (node is dom.Text) {
return node.text.trim().isEmpty;
// Treat all other types of nodes (e.g. comments) as whitespace.
return true;
/// Create an HTML element with the given name, attributes, and child nodes.
dom.Element makeElement(
String name, Map<Object, String> attributes, List<dom.Node> children) {
var result = dom.Element.tag(name);
for (var child in children) {
return result;
/// Mixin class for generating HTML.
mixin HtmlGenerator {
List<dom.Node> _html = [];
/// Add the given [node] to the HTML output.
void add(dom.Node node) {
/// Add the given [nodes] to the HTML output.
void addAll(Iterable<dom.Node> nodes) {
for (var node in nodes) {
/// Execute [callback], collecting any code that is output using [write],
/// [writeln], [add], [addAll] or [element], and return the result as a list
/// of HTML nodes.
List<dom.Node> collectHtml(void Function()? callback) {
var oldHtml = _html;
try {
_html = <dom.Node>[];
if (callback != null) {
return _html;
} finally {
_html = oldHtml;
/// Execute [callback], wrapping its output in an element with the given
/// [name] and [attributes].
void element(String name, Map<Object, String> attributes,
[void Function()? callback]) {
add(makeElement(name, attributes, collectHtml(callback)));
/// Output text without ending the current line.
void write(String text) {
/// Output text, ending the current line.
void writeln([Object obj = '']) {