LibWeb: Implement stubs for XPathEvaluator

Author: https://github.com/johannesg 🔰
Commit: f04b866cb0
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/6342
Reviewed-by: https://github.com/AtkinsSJ
Reviewed-by: https://github.com/gmta ✅

Libraries/LibWeb/XPath/XPathEvaluator.cpp

@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Bindings/XPathEvaluatorPrototype.h>
+#include <LibWeb/WebIDL/ExceptionOr.h>
+
+#include "XPathEvaluator.h"
+#include "XPathExpression.h"
+#include "XPathResult.h"
+
+namespace Web::XPath {
+
+GC_DEFINE_ALLOCATOR(XPathEvaluator);
+
+XPathEvaluator::XPathEvaluator(JS::Realm& realm)
+    : Web::Bindings::PlatformObject(realm)
+{
+}
+
+XPathEvaluator::~XPathEvaluator() = default;
+
+WebIDL::ExceptionOr<GC::Ref<XPathEvaluator>> XPathEvaluator::construct_impl(JS::Realm& realm)
+{
+    return realm.create<XPathEvaluator>(realm);
+}
+
+void XPathEvaluator::initialize(JS::Realm& realm)
+{
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(XPathEvaluator);
+    Base::initialize(realm);
+}
+
+WebIDL::ExceptionOr<GC::Ref<XPathExpression>> XPathEvaluator::create_expression(String const& expression, GC::Ptr<XPathNSResolver> resolver)
+{
+    auto& realm = this->realm();
+    return realm.create<XPathExpression>(realm, expression, resolver);
+}
+
+WebIDL::ExceptionOr<GC::Ref<XPathResult>> XPathEvaluator::evaluate(String const&, DOM::Node const&, GC::Ptr<XPathNSResolver>, WebIDL::UnsignedShort, GC::Ptr<XPathResult>)
+{
+    auto& realm = this->realm();
+    return realm.create<XPathResult>(realm);
+}
+
+GC::Ref<DOM::Node> XPathEvaluator::create_ns_resolver(GC::Ref<DOM::Node> node_resolver)
+{
+    return node_resolver;
+}
+
+}

Libraries/LibWeb/XPath/XPathEvaluator.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Forward.h>
+#include <LibWeb/WebIDL/Types.h>
+
+#include "XPathExpression.h"
+#include "XPathNSResolver.h"
+#include "XPathResult.h"
+
+namespace Web::XPath {
+
+class XPathEvaluator : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(XPathEvaluator, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(XPathEvaluator);
+
+    explicit XPathEvaluator(JS::Realm&);
+    virtual ~XPathEvaluator() override;
+
+public:
+    static WebIDL::ExceptionOr<GC::Ref<XPathEvaluator>> construct_impl(JS::Realm&);
+    virtual void initialize(JS::Realm&) override;
+
+    WebIDL::ExceptionOr<GC::Ref<XPathExpression>> create_expression(String const& expression, GC::Ptr<XPathNSResolver> resolver = nullptr);
+    WebIDL::ExceptionOr<GC::Ref<XPathResult>> evaluate(String const& expression, DOM::Node const& context_node, GC::Ptr<XPathNSResolver> resolver = nullptr, WebIDL::UnsignedShort type = 0, GC::Ptr<XPathResult> result = nullptr);
+    static GC::Ref<DOM::Node> create_ns_resolver(GC::Ref<DOM::Node> node_resolver); // legacy
+};
+
+}

Libraries/LibWeb/XPath/XPathEvaluator.idl

@@ -0,0 +1,24 @@
+#import <DOM/Node.idl>
+
+// FIXME: callback interfaces are not currently supported
+// callback interface XPathNSResolver {
+//   DOMString? lookupNamespaceURI(DOMString? prefix);
+// };
+
+// https://dom.spec.whatwg.org/#mixin-xpathevaluatorbase
+interface mixin XPathEvaluatorBase {
+    [NewObject] XPathExpression createExpression(DOMString expression, optional XPathNSResolver? resolver = null);
+    Node createNSResolver(Node nodeResolver); // legacy
+  // XPathResult.ANY_TYPE = 0
+    XPathResult evaluate(DOMString expression, Node contextNode, optional XPathNSResolver? resolver = null, optional unsigned short type = 0, optional XPathResult? result = null);
+};
+Document includes XPathEvaluatorBase;
+
+// https://dom.spec.whatwg.org/#interface-xpathevaluator
+[Exposed=Window]
+interface XPathEvaluator {
+    constructor();
+};
+
+XPathEvaluator includes XPathEvaluatorBase;
+

Libraries/LibWeb/XPath/XPathExpression.cpp

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Bindings/XPathExpressionPrototype.h>
+#include <LibWeb/DOM/Node.h>
+#include <LibWeb/Forward.h>
+
+#include "XPathEvaluator.h"
+#include "XPathExpression.h"
+#include "XPathResult.h"
+
+namespace Web::XPath {
+
+GC_DEFINE_ALLOCATOR(XPathExpression);
+
+XPathExpression::XPathExpression(JS::Realm& realm, String const& expression, GC::Ptr<XPathNSResolver> resolver)
+    : Web::Bindings::PlatformObject(realm)
+    , m_expression(expression)
+    , m_resolver(resolver)
+{
+}
+
+void XPathExpression::initialize(JS::Realm& realm)
+{
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(XPathExpression);
+    Base::initialize(realm);
+}
+
+void XPathExpression::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_resolver);
+}
+
+XPathExpression::~XPathExpression() = default;
+
+WebIDL::ExceptionOr<GC::Ref<XPathResult>> XPathExpression::evaluate(DOM::Node const&, WebIDL::UnsignedShort, GC::Ptr<XPathResult>)
+{
+    auto& realm = this->realm();
+    return realm.create<XPathResult>(realm);
+}
+
+}

Libraries/LibWeb/XPath/XPathExpression.h

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Forward.h>
+#include <LibWeb/WebIDL/Types.h>
+
+#include "XPathResult.h"
+
+namespace Web::XPath {
+
+class XPathExpression final : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(XPathExpression, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(XPathExpression);
+
+public:
+    explicit XPathExpression(JS::Realm&, String const& expression, GC::Ptr<XPathNSResolver> resolver);
+    virtual ~XPathExpression() override;
+    virtual void visit_edges(Cell::Visitor&) override;
+    virtual void initialize(JS::Realm&) override;
+
+    WebIDL::ExceptionOr<GC::Ref<XPathResult>> evaluate(DOM::Node const& context_node, WebIDL::UnsignedShort type = 0, GC::Ptr<XPathResult> result = nullptr);
+
+private:
+    String m_expression;
+    GC::Ptr<XPathNSResolver> m_resolver;
+};
+
+}

Libraries/LibWeb/XPath/XPathExpression.idl

@@ -0,0 +1,9 @@
+#import <XPath/XPathResult.idl>
+
+// https://dom.spec.whatwg.org/#interface-xpathexpression
+[Exposed=Window]
+interface XPathExpression {
+  // XPathResult.ANY_TYPE = 0
+    XPathResult evaluate(Node contextNode, optional unsigned short type = 0, optional XPathResult? result = null);
+};
+

Libraries/LibWeb/XPath/XPathNSResolver.cpp

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Object.h>
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/WebIDL/CallbackType.h>
+
+#include "XPathNSResolver.h"
+
+namespace Web::XPath {
+
+GC_DEFINE_ALLOCATOR(XPathNSResolver);
+
+GC::Ref<XPathNSResolver> XPathNSResolver::create(JS::Realm& realm, GC::Ref<WebIDL::CallbackType> callback)
+{
+    return realm.create<XPathNSResolver>(realm, callback);
+}
+
+XPathNSResolver::XPathNSResolver(JS::Realm& realm, GC::Ref<WebIDL::CallbackType> callback)
+    : JS::Object(ConstructWithPrototypeTag::Tag, realm.intrinsics().object_prototype())
+    , m_callback(callback)
+{
+}
+
+void XPathNSResolver::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_callback);
+}
+
+}

Libraries/LibWeb/XPath/XPathNSResolver.h

@@ -0,0 +1,31 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Forward.h>
+
+#include "XPathResult.h"
+
+namespace Web::XPath {
+
+class XPathNSResolver final : public JS::Object {
+    JS_OBJECT(XPathNSResolver, JS::Object);
+    GC_DECLARE_ALLOCATOR(XPathNSResolver);
+
+public:
+    [[nodiscard]] static GC::Ref<XPathNSResolver> create(JS::Realm&, GC::Ref<WebIDL::CallbackType>);
+    XPathNSResolver(JS::Realm&, GC::Ref<WebIDL::CallbackType>);
+
+    virtual ~XPathNSResolver() = default;
+    virtual void visit_edges(Cell::Visitor&) override;
+
+private:
+    GC::Ref<WebIDL::CallbackType> m_callback;
+};
+
+}

Libraries/LibWeb/XPath/XPathResult.cpp

@@ -0,0 +1,55 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibJS/Runtime/Realm.h>
+#include <LibWeb/Bindings/Intrinsics.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Bindings/XPathResultPrototype.h>
+#include <LibWeb/DOM/Node.h>
+
+#include "XPathResult.h"
+
+namespace Web::XPath {
+
+GC_DEFINE_ALLOCATOR(XPathResult);
+
+XPathResult::XPathResult(JS::Realm& realm)
+    : Web::Bindings::PlatformObject(realm)
+{
+    m_node_set_iter = m_node_set.end();
+}
+
+void XPathResult::initialize(JS::Realm& realm)
+{
+    WEB_SET_PROTOTYPE_FOR_INTERFACE(XPathResult);
+    Base::initialize(realm);
+}
+
+void XPathResult::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_node_set);
+}
+
+XPathResult::~XPathResult() = default;
+
+GC::Ptr<DOM::Node> XPathResult::iterate_next()
+{
+    if (m_node_set_iter == m_node_set.end())
+        return nullptr;
+
+    return *m_node_set_iter++;
+}
+
+GC::Ptr<DOM::Node> XPathResult::snapshot_item(int index)
+{
+    if (index < 0 || static_cast<size_t>(index) >= m_node_set.size())
+        return nullptr;
+
+    return m_node_set.at(index);
+}
+
+}

Libraries/LibWeb/XPath/XPathResult.h

@@ -0,0 +1,61 @@
+/*
+ * Copyright (c) 2025, Johannes Gustafsson <johannesgu@outlook.com>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#pragma once
+
+#include <AK/String.h>
+#include <AK/Vector.h>
+#include <LibWeb/Bindings/PlatformObject.h>
+#include <LibWeb/Forward.h>
+#include <LibWeb/WebIDL/Types.h>
+
+namespace Web::XPath {
+
+class XPathResult : public Bindings::PlatformObject {
+    WEB_PLATFORM_OBJECT(XPathResult, Bindings::PlatformObject);
+    GC_DECLARE_ALLOCATOR(XPathResult);
+
+public:
+    static WebIDL::UnsignedShort const ANY_TYPE = 0;
+    static WebIDL::UnsignedShort const NUMBER_TYPE = 1;
+    static WebIDL::UnsignedShort const STRING_TYPE = 2;
+    static WebIDL::UnsignedShort const BOOLEAN_TYPE = 3;
+    static WebIDL::UnsignedShort const UNORDERED_NODE_ITERATOR_TYPE = 4;
+    static WebIDL::UnsignedShort const ORDERED_NODE_ITERATOR_TYPE = 5;
+    static WebIDL::UnsignedShort const UNORDERED_NODE_SNAPSHOT_TYPE = 6;
+    static WebIDL::UnsignedShort const ORDERED_NODE_SNAPSHOT_TYPE = 7;
+    static WebIDL::UnsignedShort const ANY_UNORDERED_NODE_TYPE = 8;
+    static WebIDL::UnsignedShort const FIRST_ORDERED_NODE_TYPE = 9;
+
+    XPathResult(JS::Realm&);
+    virtual ~XPathResult() override;
+    virtual void initialize(JS::Realm&) override;
+    virtual void visit_edges(Cell::Visitor&) override;
+
+    WebIDL::UnsignedShort result_type() const { return m_result_type; }
+    WebIDL::Double number_value() const { return m_number_value; }
+    String string_value() { return m_string_value; }
+    WebIDL::Boolean boolean_value() const { return m_boolean_value; }
+    GC::Ptr<DOM::Node> single_node_value() { return m_node_set.is_empty() ? nullptr : m_node_set.first(); }
+    WebIDL::Boolean invalid_iterator_state() const { return m_invalid_iterator_state; }
+    WebIDL::UnsignedLong snapshot_length() const { return m_node_set.size(); }
+
+    GC::Ptr<DOM::Node> iterate_next();
+    GC::Ptr<DOM::Node> snapshot_item(int index);
+
+private:
+    WebIDL::UnsignedShort m_result_type;
+    WebIDL::Double m_number_value;
+    String m_string_value;
+    WebIDL::Boolean m_boolean_value;
+    WebIDL::Boolean m_invalid_iterator_state;
+    WebIDL::UnsignedLong m_snapshot_length;
+
+    Vector<GC::Ptr<DOM::Node>> m_node_set;
+    Vector<GC::Ptr<DOM::Node>>::Iterator m_node_set_iter;
+};
+
+}

Libraries/LibWeb/XPath/XPathResult.idl

@@ -0,0 +1,29 @@
+#import <DOM/Node.idl>
+
+// https://dom.spec.whatwg.org/#interface-xpathresult
+[Exposed=Window]
+interface XPathResult {
+    const unsigned short ANY_TYPE = 0;
+    const unsigned short NUMBER_TYPE = 1;
+    const unsigned short STRING_TYPE = 2;
+    const unsigned short BOOLEAN_TYPE = 3;
+    const unsigned short UNORDERED_NODE_ITERATOR_TYPE = 4;
+    const unsigned short ORDERED_NODE_ITERATOR_TYPE = 5;
+    const unsigned short UNORDERED_NODE_SNAPSHOT_TYPE = 6;
+    const unsigned short ORDERED_NODE_SNAPSHOT_TYPE = 7;
+    const unsigned short ANY_UNORDERED_NODE_TYPE = 8;
+    const unsigned short FIRST_ORDERED_NODE_TYPE = 9;
+
+    readonly attribute unsigned short resultType;
+    readonly attribute unrestricted double numberValue;
+    readonly attribute DOMString stringValue;
+    readonly attribute boolean booleanValue;
+    readonly attribute Node? singleNodeValue;
+    readonly attribute boolean invalidIteratorState;
+    readonly attribute unsigned long snapshotLength;
+
+    Node? iterateNext();
+    Node? snapshotItem(unsigned long index);
+};
+
+