CSS: Add support for psudo klasse :host-context

ide/css.lib/build.xml

@@ -43,6 +43,14 @@
         <!-- delete files generated by ANTLR Works when debugging the grammar -->
         <delete verbose="false" dir="src/org/netbeans/modules/css/lib/output" failonerror="false"/>
 
+        <!-- strip the path from the generated code -->
+        <mkdir dir="build/buildtool" />
+        <javac srcdir="src-buildtool" release="21" destdir="build/buildtool" />
+        <java classname="StripAntlrComments" fork="true" failonerror="true">
+            <classpath>
+                <pathelement location="build/buildtool"/>
+            </classpath>
+        </java>
     </target>
 
     <target name="test-preinit">

ide/css.lib/nbproject/project.xml

@@ -192,6 +192,11 @@
                 <package>org.netbeans.modules.css.lib.api</package>
                 <package>org.netbeans.modules.css.lib.api.properties</package>
             </friend-packages>
+            <extra-compilation-unit>
+                <package-root>src-buildtool</package-root>
+                <classpath></classpath>
+                <built-to>build/buildtool</built-to>
+            </extra-compilation-unit>
         </data>
     </configuration>
 </project>

ide/css.lib/src-buildtool/StripAntlrComments.java

@@ -0,0 +1,91 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+import static java.util.stream.Collectors.joining;
+
+/**
+ * Cleanup the generated lexer and parser files from antlr. Antlr writes
+ * timestamps and paths to the generated files. This code attempts to clean
+ * this up by removing the timestamp and replacing the full path in the header,
+ * comments and the method that report the grammar file name.
+ */
+public class StripAntlrComments {
+
+    // First line pattern:
+    // "// $ANTLR 3.5.3 /home/matthias/src/netbeans/ide/css.lib/src/org/netbeans/modules/css/lib/Css3.g 2026-10-13 18:48:07"
+    private static final Pattern FIRST_LINE_PATTERN = Pattern.compile("(// \\$ANTLR \\S+ )(.+[\\\\/]Css3\\.g)( \\d{4}-\\d{2}-\\d{2} \\d{2}:\\d{2}:\\d{2})");
+
+    public static void main(String[] args) throws IOException {
+        Path lexerPath = Path.of("src/org/netbeans/modules/css/lib/Css3Lexer.java");
+        Path parserPath = Path.of("src/org/netbeans/modules/css/lib/Css3Parser.java");
+
+        List<String> lexerCode = Files.readAllLines(lexerPath);
+        List<String> parserCode = Files.readAllLines(parserPath);
+
+        Matcher lexerMatcher = FIRST_LINE_PATTERN.matcher(lexerCode.get(0));
+        Matcher parserMatcher = FIRST_LINE_PATTERN.matcher(parserCode.get(0));
+
+        if (!lexerMatcher.find()) {
+            System.err.println("First line in " + lexerPath + " not in expected format");
+            System.exit(1);
+        }
+
+        if (!parserMatcher.find()) {
+            System.err.println("First line in " + parserPath + " not in expected format");
+            System.exit(1);
+        }
+
+        String lexerHeaderPath = lexerMatcher.group(2);
+        String parserHeaderPath = parserMatcher.group(2);
+
+        if (!lexerHeaderPath.equals(parserHeaderPath)) {
+            System.err.println("Paths in first lines of " + lexerPath + " and " + parserPath + " don't match:" );
+            System.err.println("Css3Lexer.java:  " + lexerHeaderPath);
+            System.err.println("Css3Parser.java: " + parserHeaderPath);
+            System.exit(1);
+        }
+
+        lexerCode.set(0, lexerMatcher.group(1) + "Css3.g");
+        parserCode.set(0, parserMatcher.group(1) + "Css3.g");
+
+        for(int i = 1; i < lexerCode.size(); i++) {
+            String strippedLine = lexerCode.get(i)
+                    .replace("// " + lexerHeaderPath, "// Css3.g")
+                    .replace("\"" + lexerHeaderPath, "\"Css3.g");
+            lexerCode.set(i, strippedLine);
+        }
+
+        for(int i = 1; i < parserCode.size(); i++) {
+            String strippedLine = parserCode.get(i)
+                    .replace("// " + lexerHeaderPath, "// Css3g")
+                    .replace("\"" + lexerHeaderPath, "\"Css3.g");
+            parserCode.set(i, strippedLine);
+        }
+
+        Files.writeString(lexerPath, lexerCode.stream().collect(joining("\n")));
+        Files.writeString(parserPath, parserCode.stream().collect(joining("\n")));
+    }
+}

ide/css.lib/src/org/netbeans/modules/css/lib/Css3.g

@@ -1080,6 +1080,7 @@ slAttributeValue
 
 pseudo
     : (( COLON | DCOLON ) {tokenNameEquals("host")}? IDENT (ws? LPAREN))=> ( COLON | DCOLON ) IDENT ( ws? LPAREN ws? ( selector ws?)? RPAREN )?
+    | (( COLON | DCOLON ) {tokenNameEquals("host-context")}? IDENT (ws? LPAREN))=> ( COLON | DCOLON ) IDENT ( ws? LPAREN ws? ( selector ws?)? RPAREN )?
     | (( COLON | DCOLON ) {tokenNameEquals("slotted")}? IDENT (ws? LPAREN))=> ( COLON | DCOLON ) IDENT ( ws? LPAREN ws? ( selector ws?)? RPAREN )
     | ( COLON | DCOLON )
              (