Prepend to classpath in args file when present

Summary:
Infer prepends the directory containing the ananotation processor and
the current working directory to the classpath javac option.  This diff
enables prepending these to the classpath when it is passing in an args
file (as the classpath can get too long to pass on the command line).

Reviewed By: jvillard

Differential Revision: D3270348

fbshipit-source-id: 208077f

infer/lib/python/inferlib/jwlib.py

@@ -12,8 +12,10 @@ from __future__ import print_function
 from __future__ import unicode_literals
 
 import argparse
+import codecs
 import os
 import subprocess
+import sys
 import tempfile
 import time
 
@@ -32,6 +34,12 @@ parser.add_argument('-bootclasspath', type=utils.decode)
 parser.add_argument('-d', dest='classes_out', default=current_directory)
 parser.add_argument('-processorpath', type=utils.decode, dest='processorpath')
 parser.add_argument('-processor', type=utils.decode, dest='processor')
+parser.add_argument('-o', '--out', metavar='<directory>',
+                    default=utils.encode(config.DEFAULT_INFER_OUT),
+                    dest='infer_out',
+                    type=utils.decode,
+                    action=utils.AbsolutePathAction,
+                    help='Set the Infer results directory')
 
 
 def _get_javac_args(args):
@@ -94,7 +102,6 @@ class CompilerCall(object):
                 raise AnnotationProcessorNotFound(config.ANNOT_PROCESSOR_JAR)
             if self.args.classes_out is not None:
                 javac_cmd += ['-d', self.args.classes_out]
-            javac_cmd += self.remaining_args
 
             javac_cmd.append('-J-Duser.language=en')
 
@@ -110,6 +117,37 @@ class CompilerCall(object):
                 classpath = os.pathsep.join([config.ANNOT_PROCESSOR_JAR,
                                              classpath])
 
+            at_args = [
+                arg for arg in self.remaining_args if arg.startswith('@')]
+            found_classpath = False
+            for at_arg in at_args:
+                # remove @ character
+                args_file_name = at_arg[1:]
+                with codecs.open(args_file_name, 'r',
+                                 encoding=config.CODESET) as args_file:
+                    args_file_contents = args_file.read()
+                prefix_suffix = args_file_contents.split('-classpath\n', 1)
+                if len(prefix_suffix) == 2:
+                    prefix, suffix = prefix_suffix
+                    with tempfile.NamedTemporaryFile(
+                            dir=self.args.infer_out,
+                            prefix=args_file_name + '_',
+                            suffix='_cp',
+                            delete=False) as args_file_cp:
+                        args_file_name_cp = args_file_cp.name
+                        args_file_cp.write(
+                            prefix + '-classpath\n' + classpath + ':' + suffix)
+                        at_arg_cp = '@' + args_file_name_cp
+                        self.remaining_args = [
+                            at_arg_cp if arg == at_arg else arg
+                            for arg in self.remaining_args]
+                        found_classpath = True
+                        break
+
+            javac_cmd += self.remaining_args
+
+            if not found_classpath:
+                # -classpath option not found in any args file
                 javac_cmd += ['-classpath', classpath]
 
             # this overrides the default mechanism for discovering annotation