Merge "Buck: Activate error prone checks"

Documentation/dev-buck.txt

@@ -685,6 +685,25 @@ Watchman can either be de-installed or disabled. See
 link:#buck-daemon[Using Buck daemon] section above how to temporarily
 disable `buckd`.
 
+== Error Prone integration
+
+link:http://errorprone.info[Error Prone] is a static analysis tool for
+Java that catches common programming mistakes at compile-time. It can
+be permanenty or instantly activated. For permanent activation, add these
+lines to your `.buckconfig.local` file in gerrit tree:
+
+```
+  [sanitizers]
+    error_prone = 1
+```
+
+For instant activation, pass this config option to the `build` or `test`
+commands:
+
+```
+  buck build --config sanitizers.error_prone=1 gerrit
+```
+
 == Troubleshooting Buck
 
 In some cases problems with Buck itself need to be investigated. See for example

lib/BUCK

@@ -310,3 +310,10 @@ maven_jar(
   sha1 = '198ea005f41219f038f4291f0b0e9f3259730e92',
   license = 'icu4j',
 )
+
+maven_jar(
+  name = 'errorprone',
+  id = 'com.google.errorprone:error_prone_ant:2.0.15',
+  sha1 = '607e3866e2ee25b74708c2898f84eac2f5452d2f',
+  license = 'Apache2.0',
+)

tools/default.defs

@@ -41,9 +41,15 @@ def java_test(*args, **kwargs):
 
 # Munge kwargs to set Gerrit-specific defaults.
 def _munge_args(kwargs):
+  if read_config('sanitizers', 'error_prone'):
+    _set_error_prone(kwargs)
   _set_auto_value(kwargs)
   _set_extra_arguments(kwargs)
 
+def _set_error_prone(kwargs):
+  kwargs['javac_jar'] = '//lib:errorprone'
+  kwargs['compiler_class_name'] = 'com.google.errorprone.ErrorProneJavaCompiler'
+
 def _set_extra_arguments(kwargs):
   ext = 'extra_arguments'
   if ext not in kwargs: