8370865: Incorrect parser error for compact source files and multi-variable declarations

Reviewed-by: vromero

Author: lahodaj

src/jdk.compiler/share/classes/com/sun/tools/javac/parser/JavacParser.java

@@ -4933,7 +4933,8 @@ private List<JCTree> topLevelMethodOrFieldDeclaration(JCModifiers mods, Comment
             }
 
             // Field
-            if (!isVoid && typarams.isEmpty() && (token.kind == EQ || token.kind == SEMI)) {
+            if (!isVoid && typarams.isEmpty() &&
+                (token.kind == EQ || token.kind == SEMI || token.kind == COMMA)) {
                 List<JCTree> defs =
                         variableDeclaratorsRest(pos, mods, type, name, false, dc,
                                 new ListBuffer<JCTree>(), false).toList();

test/langtools/tools/javac/ImplicitClass/MultipleFields.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/**
+ * @test
+ * @bug 8370865
+ * @summary Check that multiple comma-separated fields work
+ * @library /tools/lib
+ * @modules jdk.compiler/com.sun.tools.javac.api
+ *          jdk.compiler/com.sun.tools.javac.main
+ *          jdk.compiler/com.sun.tools.javac.util
+ * @build toolbox.ToolBox toolbox.JavacTask
+ * @run main MultipleFields
+*/
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.List;
+import java.util.Objects;
+
+import toolbox.TestRunner;
+import toolbox.JavacTask;
+import toolbox.JavaTask;
+import toolbox.Task;
+import toolbox.ToolBox;
+
+public class MultipleFields extends TestRunner {
+
+    private ToolBox tb;
+
+    public static void main(String... args) throws Exception {
+        new MultipleFields().runTests();
+    }
+
+    MultipleFields() {
+        super(System.err);
+        tb = new ToolBox();
+    }
+
+    public void runTests() throws Exception {
+        runTests(m -> new Object[] { Paths.get(m.getName()) });
+    }
+
+    @Test
+    public void testWithExplicitImport(Path base) throws Exception {
+        Path current = base.resolve(".");
+        Path src = current.resolve("src");
+        Path classes = current.resolve("classes");
+        tb.writeFile(src.resolve("Test.java"),
+                     """
+                     int f1, f2;
+
+                     public void main() {
+                         f1 = 1;
+                         f2 = f1 + 1;
+                         System.out.println("field: " + f1 + "/" + f2);
+                     }
+                     """);
+
+        Files.createDirectories(classes);
+
+        new JavacTask(tb)
+            .outdir(classes)
+            .files(tb.findJavaFiles(src))
+            .run(Task.Expect.SUCCESS)
+            .writeAll();
+
+        var out = new JavaTask(tb)
+                .classpath(classes.toString())
+                .className("Test")
+                .run()
+                .writeAll()
+                .getOutputLines(Task.OutputKind.STDOUT);
+
+        var expectedOut = List.of("field: 1/2");
+
+        if (!Objects.equals(expectedOut, out)) {
+            throw new AssertionError("Incorrect Output, expected: " + expectedOut +
+                                      ", actual: " + out);
+
+        }
+    }
+}

test/langtools/tools/javac/parser/JavacParserTest.java

@@ -23,7 +23,7 @@
 
 /*
  * @test
- * @bug 7073631 7159445 7156633 8028235 8065753 8205418 8205913 8228451 8237041 8253584 8246774 8256411 8256149 8259050 8266436 8267221 8271928 8275097 8293897 8295401 8304671 8310326 8312093 8312204 8315452 8337976 8324859 8344706 8351260
+ * @bug 7073631 7159445 7156633 8028235 8065753 8205418 8205913 8228451 8237041 8253584 8246774 8256411 8256149 8259050 8266436 8267221 8271928 8275097 8293897 8295401 8304671 8310326 8312093 8312204 8315452 8337976 8324859 8344706 8351260 8370865
  * @summary tests error and diagnostics positions
  * @author  Jan Lahoda
  * @modules jdk.compiler/com.sun.tools.javac.api
@@ -3076,6 +3076,54 @@ void testVeryBrokenTypeWithAnnotationsMinimal() throws IOException {
         ct.parse().iterator().next();
     }
 
+    @Test //JDK-8370865
+    void testCompactSourceFileMultiField1() throws IOException {
+        String code = """
+                      int i, j, k;
+                      void main() {}
+                      """;
+        DiagnosticCollector<JavaFileObject> coll =
+                new DiagnosticCollector<>();
+        JavacTaskImpl ct = (JavacTaskImpl) tool.getTask(null, fm, coll,
+                List.of("-XDrawDiagnostics"),
+                null, Arrays.asList(new MyFileObject(code)));
+        //no exceptions:
+        ct.parse().iterator().next();
+        List<String> codes = new LinkedList<>();
+
+        for (Diagnostic<? extends JavaFileObject> d : coll.getDiagnostics()) {
+            codes.add(d.getLineNumber() + ":" + d.getColumnNumber() + ":" + d.getCode());
+        }
+
+        assertEquals("testCompactSourceFileMultiField1: " + codes,
+                     List.of(),
+                     codes);
+    }
+
+    @Test //JDK-8370865
+    void testCompactSourceFileMultiField2() throws IOException {
+        String code = """
+                      int i, j = 0, k = 0;
+                      void main() {}
+                      """;
+        DiagnosticCollector<JavaFileObject> coll =
+                new DiagnosticCollector<>();
+        JavacTaskImpl ct = (JavacTaskImpl) tool.getTask(null, fm, coll,
+                List.of("-XDrawDiagnostics"),
+                null, Arrays.asList(new MyFileObject(code)));
+        //no exceptions:
+        ct.parse().iterator().next();
+        List<String> codes = new LinkedList<>();
+
+        for (Diagnostic<? extends JavaFileObject> d : coll.getDiagnostics()) {
+            codes.add(d.getLineNumber() + ":" + d.getColumnNumber() + ":" + d.getCode());
+        }
+
+        assertEquals("testCompactSourceFileMultiField2: " + codes,
+                     List.of(),
+                     codes);
+    }
+
     void run(String[] args) throws Exception {
         int passed = 0, failed = 0;
         final Pattern p = (args != null && args.length > 0)