commit f46e0702f4409d982b79cab9a3789b35090d46a4
Author: John Sirois <john.sirois@gmail.com>
Date:   Mon Sep 26 20:01:03 2016 -0600

    Fix handling of method specs.
    
    Previously the method spec handling code did not guard against non-test
    classes and would throw an NPE. This change adds a failing test and
    fixes the handling to deal with `Optional`. The `Spec` class is made
    immutable in the process to improve the code's ability to be reasoned
    about.
    
    Testing Done:
    I noticed this issue when attempting the following:
    ```
    ./pants test.junit \
      --no-timeouts \
      --open \
      --coverage-open \
      --test=tests/java/org/pantsbuild/args4j/ParserTest.java#test{Failure,Success} \
      tests/java/org/pantsbuild/args4j/::
    ...
    11:26:39 00:03       [run]
                         OpenJDK 64-Bit Server VM warning: ignoring option MaxPermSize=256m; support was removed in 8.0
                         OpenJDK 64-Bit Server VM warning: ignoring option UseSplitVerifier; support was removed in 8.0
                         Auto-detected 8 processors, using -parallel-threads=8
                         Exception in thread "main" java.lang.NullPointerException
                            at __shaded_by_pants__.org.pantsbuild.tools.junit.impl.SpecParser.addMethod(SpecParser.java:130)
                            at __shaded_by_pants__.org.pantsbuild.tools.junit.impl.SpecParser.parse(SpecParser.java:61)
                            at __shaded_by_pants__.org.pantsbuild.tools.junit.impl.ConsoleRunnerImpl.run(ConsoleRunnerImpl.java:455)
                            at __shaded_by_pants__.org.pantsbuild.tools.junit.impl.ConsoleRunnerImpl.main(ConsoleRunnerImpl.java:845)
                            at org.pantsbuild.tools.junit.ConsoleRunner.main(ConsoleRunner.java:12)
    
                       Test failed:
                       java org.pantsbuild.tools.junit.ConsoleRunner ... exited non-zero (1); 0 failed 0 targets.
    ...
    ```
    
    Locally green using `./pants test-changed`.
    
    CI went green here:
      https://travis-ci.org/pantsbuild/pants/builds/162902557
    
    Bugs closed: 3902
    
    Reviewed at https://rbcommons.com/s/twitter/r/4258/

 .../tools/junit/impl/ConsoleRunnerImpl.java        | 15 ++--
 src/java/org/pantsbuild/tools/junit/impl/Spec.java | 40 ++++++----
 .../pantsbuild/tools/junit/impl/SpecException.java |  8 +-
 .../pantsbuild/tools/junit/impl/SpecParser.java    | 90 +++++++++-------------
 4 files changed, 70 insertions(+), 83 deletions(-)