LibWeb: Implement the "unlink" editing command

Author: https://github.com/gmta
Commit: https://github.com/LadybirdBrowser/ladybird/commit/e686328cbd8
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/3216

Libraries/LibWeb/Editing/Commands.cpp

@@ -1439,6 +1439,41 @@ bool command_underline_action(DOM::Document& document, String const&)
     return true;
 }
 
+// https://w3c.github.io/editing/docs/execCommand/#the-unlink-command
+bool command_unlink_action(DOM::Document& document, String const&)
+{
+    // 1. Let hyperlinks be a list of every a element that has an href attribute and is contained in the active range or
+    //    is an ancestor of one of its boundary points.
+    Vector<GC::Ref<DOM::Element>> hyperlinks;
+    if (auto range = active_range(document)) {
+        auto node_matches = [](GC::Ref<DOM::Node> node) {
+            return is<HTML::HTMLAnchorElement>(*node)
+                && static_cast<HTML::HTMLAnchorElement&>(*node).has_attribute(HTML::AttributeNames::href);
+        };
+        range->for_each_contained([&](GC::Ref<DOM::Node> node) {
+            if (node_matches(node))
+                hyperlinks.append(static_cast<DOM::Element&>(*node));
+            return IterationDecision::Continue;
+        });
+        auto add_matching_ancestors = [&](GC::Ref<DOM::Node> node) {
+            node->for_each_ancestor([&](GC::Ref<DOM::Node> ancestor) {
+                if (node_matches(ancestor))
+                    hyperlinks.append(static_cast<DOM::Element&>(*ancestor));
+                return IterationDecision::Continue;
+            });
+        };
+        add_matching_ancestors(range->start_container());
+        add_matching_ancestors(range->end_container());
+    }
+
+    // 2. Clear the value of each member of hyperlinks.
+    for (auto member : hyperlinks)
+        clear_the_value(CommandNames::unlink, member);
+
+    // 3. Return true.
+    return true;
+}
+
 static Array const commands {
     // https://w3c.github.io/editing/docs/execCommand/#the-backcolor-command
     CommandDefinition {
@@ -1557,6 +1592,11 @@ static Array const commands {
         .action = command_underline_action,
         .inline_activated_values = { "underline"sv },
     },
+    // https://w3c.github.io/editing/docs/execCommand/#the-unlink-command
+    CommandDefinition {
+        .command = CommandNames::unlink,
+        .action = command_unlink_action,
+    },
 };
 
 Optional<CommandDefinition const&> find_command_definition(FlyString const& command)

Libraries/LibWeb/Editing/Commands.h

@@ -52,5 +52,6 @@ bool command_subscript_indeterminate(DOM::Document const&);
 bool command_superscript_action(DOM::Document&, String const&);
 bool command_superscript_indeterminate(DOM::Document const&);
 bool command_underline_action(DOM::Document&, String const&);
+bool command_unlink_action(DOM::Document&, String const&);
 
 }

Tests/LibWeb/Text/expected/Editing/execCommand-unlink.txt

@@ -0,0 +1,2 @@
+d1 contents: "ladybird"
+d2 contents: "ladybird"

Tests/LibWeb/Text/input/Editing/execCommand-unlink.html

@@ -0,0 +1,23 @@
+<script src="../include.js"></script>
+<div contenteditable="true" id="d1"><a href="https://ladybird.dev">ladybird</a></div>
+<div contenteditable="true" id="d2">lady<a href="https://ladybird.dev">bird</a></div>
+<script>
+    test(() => {
+        const range = document.createRange();
+        getSelection().addRange(range);
+
+        // Unlink d1's ladybird
+        const div1 = document.querySelector('#d1');
+        range.setStart(div1.childNodes[0].childNodes[0], 0);
+        range.setEnd(div1.childNodes[0].childNodes[0], 8);
+        document.execCommand('unlink');
+        println(`d1 contents: "${div1.innerHTML}"`);
+
+        // Unlink d2's 'bird'
+        const div2 = document.querySelector('#d2');
+        range.setStart(div2.childNodes[1].childNodes[0], 2);
+        range.setEnd(div2.childNodes[1].childNodes[0], 3);
+        document.execCommand('unlink');
+        println(`d2 contents: "${div2.innerHTML}"`);
+    });
+</script>