8258897: wrong translation of capturing local classes inside nested lambdas

Co-authored-by: Bernard Blaser <bsrbnd@openjdk.org>
Reviewed-by: jlahoda

src/jdk.compiler/share/classes/com/sun/tools/javac/comp/LambdaToMethod.java

@@ -2068,7 +2068,13 @@ public class LambdaToMethod extends TreeTranslator {
                         };
                         break;
                     case LOCAL_VAR:
-                        ret = new VarSymbol(sym.flags() & FINAL, sym.name, sym.type, translatedSym);
+                        ret = new VarSymbol(sym.flags() & FINAL, sym.name, sym.type, translatedSym) {
+                            @Override
+                            public Symbol baseSymbol() {
+                                //keep mapping with original symbol
+                                return sym;
+                            }
+                        };
                         ((VarSymbol) ret).pos = ((VarSymbol) sym).pos;
                         // If sym.data == ElementKind.EXCEPTION_PARAMETER,
                         // set ret.data = ElementKind.EXCEPTION_PARAMETER too.

src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Lower.java

@@ -1213,7 +1213,7 @@ public class Lower extends TreeTranslator {
                 //sym is a local variable - check the lambda translation map to
                 //see if sym has been translated to something else in the current
                 //scope (by LambdaToMethod)
-                Symbol translatedSym = lambdaTranslationMap.get(sym);
+                Symbol translatedSym = lambdaTranslationMap.get(sym.baseSymbol());
                 if (translatedSym != null) {
                     tree = make.at(tree.pos).Ident(translatedSym);
                 }

test/langtools/tools/javac/lambda/8258897/CaptureVariables.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2021, 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 8258897
+ * @summary Checks translation of capturing local classes inside nested lambdas
+ * @run main CaptureVariables
+ */
+
+import java.util.function.Supplier;
+
+public class CaptureVariables {
+    static Supplier<Integer> supplier1 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> new Local().i).get();
+    };
+
+    static Supplier<Integer> supplier2 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> ((Supplier<Integer>) () -> new Local().i).get()).get();
+    };
+
+    Supplier<Integer> supplier3 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> new Local().i).get();
+    };
+
+    Supplier<Integer> supplier4 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> ((Supplier<Integer>) () -> new Local().i).get()).get();
+    };
+
+    public static void main(String[] args) {
+        assert supplier1.get() == 11;
+        assert supplier2.get() == 11;
+        assert new CaptureVariables().supplier3.get() == 11;
+        assert new CaptureVariables().supplier4.get() == 11;
+    }
+}

test/langtools/tools/javac/lambda/8258897/CaptureVariablesAnonymous.java

@@ -0,0 +1,92 @@
+/*
+ * Copyright (c) 2021, 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 8258897
+ * @summary Checks translation of capturing local classes inside nested lambdas
+ * @run main CaptureVariablesAnonymous
+ */
+
+import java.util.function.Supplier;
+
+public class CaptureVariablesAnonymous {
+    static Supplier<Integer> supplier1 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> new Local() {}.i).get();
+    };
+
+    static Supplier<Integer> supplier2 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> ((Supplier<Integer>) () -> new Local() {}.i).get()).get();
+    };
+
+    Supplier<Integer> supplier3 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> new Local() {}.i).get();
+    };
+
+    Supplier<Integer> supplier4 = () -> {
+        boolean b0 = false;
+        int i0 = 6;
+        boolean b1 = false;
+        String s0 = "hello";
+
+        class Local {
+            int i = s0.length() + i0;
+        }
+
+        return ((Supplier<Integer>) () -> ((Supplier<Integer>) () -> new Local() {}.i).get()).get();
+    };
+
+    public static void main(String[] args) {
+        assert supplier1.get() == 11;
+        assert supplier2.get() == 11;
+        assert new CaptureVariablesAnonymous().supplier3.get() == 11;
+        assert new CaptureVariablesAnonymous().supplier4.get() == 11;
+    }
+}