Fall back to transitive classpath for no.such.pkg errors.

With -XDshouldStopPolicyIfError=INIT (the default) and -XDcompilePolicy=byfile
(not the default), javac will stop compiling after emitting no.such.pkg and
before any missing symbol errors are reported. The reduced classpath builder
needs to fall back to the transitive classpath in this case.

This currently works because with -XDcompilePolicy=todo (the default), javac
attributes compilation units even if they have with syntax errors to avoid
"surprising existing users". [1]

[1] http://hg.openjdk.java.net/jdk9/dev/langtools/file/7fd155b7041c/test/tools/javac/policy/test3/Test.java

--
MOS_MIGRATED_REVID=101175706

1 files changed, 7 insertions, 2 deletions

diff --git a/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/ReducedClasspathJavaLibraryBuilder.java b/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/ReducedClasspathJavaLibraryBuilder.java
index ebc1f0f006..1ff9886add 100644
--- a/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/ReducedClasspathJavaLibraryBuilder.java
+++ b/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/ReducedClasspathJavaLibraryBuilder.java
@@ -21,6 +21,7 @@ import com.sun.tools.javac.main.Main.Result;
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.io.StringWriter;
+import java.util.regex.Pattern;
 
 /**
  * A variant of SimpleJavaLibraryBuilder that attempts to reduce the compile-time classpath right
@@ -76,10 +77,14 @@ public class ReducedClasspathJavaLibraryBuilder extends SimpleJavaLibraryBuilder
     }
     return result;
   }
-  
+
+  private static final Pattern MISSING_PACKAGE =
+      Pattern.compile("error: package ([\\p{javaJavaIdentifierPart}\\.]+) does not exist");
+
   private boolean hasRecognizedError(String javacOutput) {
     return javacOutput.contains("error: cannot access")
         || javacOutput.contains("error: cannot find symbol")
-        || javacOutput.contains("com.sun.tools.javac.code.Symbol$CompletionFailure");
+        || javacOutput.contains("com.sun.tools.javac.code.Symbol$CompletionFailure")
+        || MISSING_PACKAGE.matcher(javacOutput).find();
   }
 }