Added a simple rewriter to the catch block finder of ASTConverter: If it can't find it, it used to return -1, which is exceedingly useless and causes no end of bugs. Changed it to returning the start point of the search, which is a more useful fallback.

2 files changed, 110 insertions, 0 deletions

diff --git a/src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java b/src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java
new file mode 100644
index 00000000..1402138b
--- /dev/null
+++ b/src_eclipseagent/lombok/eclipse/agent/EclipseASTConverterTransformer.java
@@ -0,0 +1,100 @@
+/*
+ * Copyright © 2009 Reinier Zwitserloot and Roel Spilker.
+ * 
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ * 
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ * 
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package lombok.eclipse.agent;
+
+import org.objectweb.asm.ClassAdapter;
+import org.objectweb.asm.ClassReader;
+import org.objectweb.asm.ClassVisitor;
+import org.objectweb.asm.ClassWriter;
+import org.objectweb.asm.MethodAdapter;
+import org.objectweb.asm.MethodVisitor;
+import org.objectweb.asm.Opcodes;
+
+/**
+ * Transforms Eclipse's <code>org.eclipse.jdt.core.dom.ASTConverter</code> class, which sometimes rescans bits and pieces
+ * of source files because Eclipse's own AST doesn't actually have enough information for eclipse (why they don't just fix
+ * the AST tree generator is beyond me). At any rate, for catch blocks generated by lombok, eclipse tries to rescan the
+ * source file to find the source position of the catch statement, which will of course fail as there's nothing there.
+ * We will fix the code to return the original starting position, which is a pretty good simile, instead of '-1', which
+ * screws up all sorts of things.
+ * 
+ * Transformations applied:<ul>
+ * <li>The <code>retrieveStartingCatchPosition(int, int)</code> method is instrumented to return its first parameter
+ * instead of the constant -1.</li></ul>
+ */
+class EclipseASTConverterTransformer {
+	byte[] transform(byte[] classfileBuffer) {
+		ClassReader reader = new ClassReader(classfileBuffer);
+		ClassWriter writer = new ClassWriter(reader, 0);
+		
+		ClassAdapter adapter = new ASTConverterPatcherAdapter(writer);
+		reader.accept(adapter, 0);
+		return writer.toByteArray();
+	}
+	
+	static RuntimeException sneakyThrow(Throwable t) {
+		if ( t == null ) throw new NullPointerException("t");
+		EclipseASTConverterTransformer.<RuntimeException>sneakyThrow0(t);
+		return null;
+	}
+	
+	@SuppressWarnings("unchecked")
+	private static <T extends Throwable> void sneakyThrow0(Throwable t) throws T {
+		throw (T)t;
+	}
+	
+	private static class ASTConverterPatcherAdapter extends ClassAdapter {
+		public ASTConverterPatcherAdapter(ClassVisitor cv) {
+			super(cv);
+		}
+		
+		@Override public MethodVisitor visitMethod(int access, String name, String desc,
+				String signature, String[] exceptions) {
+			MethodVisitor writerVisitor = super.visitMethod(access, name, desc, signature, exceptions);
+			if ( !name.equals("retrieveStartingCatchPosition") ) return writerVisitor;
+			
+			return new RetrieveStartingCatchPositionPatcher(writerVisitor);
+		}
+	}
+	
+	static class RetrieveStartingCatchPositionPatcher extends MethodAdapter {
+		RetrieveStartingCatchPositionPatcher(MethodVisitor mv) {
+			super(mv);
+		}
+		
+		int count = 0;
+		@Override public void visitInsn(int opcode) {
+			if ( opcode == Opcodes.IRETURN ) {
+				if ( count++ == 0 ) {
+					super.visitInsn(opcode);
+					return;
+				}
+				//replaces: "return -1" with "return [firstParam]";
+				super.visitInsn(Opcodes.POP);
+				super.visitVarInsn(Opcodes.ILOAD, 1);
+				super.visitInsn(Opcodes.IRETURN);
+			} else {
+				super.visitInsn(opcode);
+			}
+		}
+	}
+}
diff --git a/src_eclipseagent/lombok/eclipse/agent/EclipsePatcher.java b/src_eclipseagent/lombok/eclipse/agent/EclipsePatcher.java
index 02cc533d..67371948 100644
--- a/src_eclipseagent/lombok/eclipse/agent/EclipsePatcher.java
+++ b/src_eclipseagent/lombok/eclipse/agent/EclipsePatcher.java
@@ -71,6 +71,15 @@ public class EclipsePatcher {
 				}
 			}
 			
+			if ( ECLIPSE_ASTCONVERTER_CLASS_NAME.equals(className) ) {
+				try {
+					return runTransform("lombok.eclipse.agent.EclipseASTConverterTransformer", classfileBuffer);
+				} catch ( Throwable t ) {
+					System.err.println("Wasn't able to patch eclipse's ASTConverter class:");
+					t.printStackTrace();
+				}
+			}
+			
 			return null;
 		}
 	}
@@ -87,6 +96,7 @@ public class EclipsePatcher {
 	
 	static final String ECLIPSE_CUD_CLASS_NAME = "org/eclipse/jdt/internal/compiler/ast/CompilationUnitDeclaration";
 	static final String ECLIPSE_PARSER_CLASS_NAME = "org/eclipse/jdt/internal/compiler/parser/Parser";
+	static final String ECLIPSE_ASTCONVERTER_CLASS_NAME = "org/eclipse/jdt/core/dom/ASTConverter";
 	
 	public static void agentmain(String agentArgs, Instrumentation instrumentation) throws Exception {
 		registerPatcher(instrumentation, true);