Issue #106: Retain error messages from annotation processors (#170)

* Issue #106: Retain error messages from annotation processors
Fix #106

Author: mthmulders

plexus-compilers/plexus-compiler-javac/src/main/java/org/codehaus/plexus/compiler/javac/JavacCompiler.java

@@ -755,6 +755,10 @@ else if ( hasPointer )
                 errors.add( new CompilerMessage( buffer.toString(), CompilerMessage.Kind.ERROR ) );
                 return errors;
             }
+            else if ( line.startsWith( "An annotation processor threw an uncaught exception." ) ) {
+                CompilerMessage annotationProcessingError = parseAnnotationProcessorStream( input );
+                errors.add( annotationProcessingError );
+            }
 
             // new error block?
             if ( !line.startsWith( " " ) && hasPointer )
@@ -800,6 +804,23 @@ else if ( ( buffer.length() == 0 ) && isMisc( line ) )
         }
     }
 
+    private static CompilerMessage parseAnnotationProcessorStream( final BufferedReader input )
+            throws IOException
+    {
+        String line = input.readLine();
+        final StringBuilder buffer = new StringBuilder();
+
+        while (line != null) {
+            if (!line.startsWith( "Consult the following stack trace for details." )) {
+                buffer.append(line);
+                buffer.append(EOL);
+            }
+            line = input.readLine();
+        }
+
+        return new CompilerMessage( buffer.toString(), CompilerMessage.Kind.ERROR );
+    }
+
     private static boolean isMisc( String line )
     {
         return startsWithPrefix( line, MISC_PREFIXES );

plexus-compilers/plexus-compiler-javac/src/test/java/org/codehaus/plexus/compiler/javac/JavacCompilerTest.java

@@ -1,6 +1,16 @@
 package org.codehaus.plexus.compiler.javac;
 
+import org.codehaus.plexus.compiler.CompilerMessage;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.StringReader;
+import java.util.List;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.collection.IsCollectionWithSize.hasSize;
 
 /*
  * Licensed to the Apache Software Foundation (ASF) under one
@@ -33,4 +43,36 @@ public void setUp()
         super.setUp();
         setForceJavacCompilerUse( true );
     }
+
+    @Test
+    void parseModernStream_withAnnotationProcessingErrors() throws IOException
+    {
+        String input =
+                "\n" +
+                "\n" +
+                "An annotation processor threw an uncaught exception.\n" +
+                "Consult the following stack trace for details.\n" +
+                "java.lang.IllegalAccessError: class lombok.javac.apt.LombokProcessor (in unnamed module @0x1da51a35) cannot access class com.sun.tools.javac.processing.JavacProcessingEnvironment (in module jdk.compiler) because module jdk.compiler does not export com.sun.tools.javac.processing to unnamed module @0x1da51a35\n" +
+                "\tat lombok.javac.apt.LombokProcessor.getJavacProcessingEnvironment(LombokProcessor.java:433)\n" +
+                "\tat lombok.javac.apt.LombokProcessor.init(LombokProcessor.java:92)\n" +
+                "\tat lombok.core.AnnotationProcessor$JavacDescriptor.want(AnnotationProcessor.java:160)\n" +
+                "\tat lombok.core.AnnotationProcessor.init(AnnotationProcessor.java:213)\n" +
+                "\tat lombok.launch.AnnotationProcessorHider$AnnotationProcessor.init(AnnotationProcessor.java:64)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment$ProcessorState.<init>(JavacProcessingEnvironment.java:702)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment$DiscoveredProcessors$ProcessorStateIterator.next(JavacProcessingEnvironment.java:829)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment.discoverAndRunProcs(JavacProcessingEnvironment.java:925)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment$Round.run(JavacProcessingEnvironment.java:1269)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.processing.JavacProcessingEnvironment.doProcessing(JavacProcessingEnvironment.java:1384)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.main.JavaCompiler.processAnnotations(JavaCompiler.java:1261)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:935)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:317)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.main.Main.compile(Main.java:176)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.Main.compile(Main.java:64)\n" +
+                "\tat jdk.compiler/com.sun.tools.javac.Main.main(Main.java:50)\n";
+
+        List<CompilerMessage> compilerMessages = JavacCompiler.parseModernStream( 1,
+                new BufferedReader( new StringReader( input ) ) );
+
+        assertThat( compilerMessages, hasSize( 1 ) );
+    }
 }