print more info about ant/gradle/make/mvn capture

Summary: public
Print "Capturing..." message, and some info in case it fails, eg:

  $ cd examples/android_hello/
  $ infer -- ./gradlew build
  Running and capturing gradle compilation...
  [... stuff ...]
  $ infer -- ./gradlew build
  Running and capturing gradle compilation...
  Nothing to compile. Try running `./gradlew clean` first.

Reviewed By: jeremydubreil

Differential Revision: D2637024

fb-gh-sync-id: 0e8867d

infer/lib/python/inferlib/capture/ant.py

@@ -77,4 +77,5 @@ class AntCapture:
 
     def capture(self):
         cmds = self.get_infer_commands(util.get_build_output(self.build_cmd))
-        return util.run_commands(cmds)
+        clean_cmd = '%s clean' % self.build_cmd[0]
+        return util.run_compilation_commands(cmds, clean_cmd)

infer/lib/python/inferlib/capture/gradle.py

@@ -80,5 +80,7 @@ class GradleCapture:
         return calls
 
     def capture(self):
+        print('Running and capturing gradle compilation...')
         cmds = self.get_infer_commands(util.get_build_output(self.build_cmd))
-        return util.run_commands(cmds)
+        clean_cmd = '%s clean' % self.build_cmd[0]
+        return util.run_compilation_commands(cmds, clean_cmd)

infer/lib/python/inferlib/capture/make.py

@@ -58,6 +58,15 @@ class MakeCapture:
             env = self.get_envvars()
             logging.info('Running command %s with env:\n%s' % (self.cmd, env))
             subprocess.check_call(self.cmd, env=env)
+            capture_dir = os.path.join(self.args.infer_out, 'captured')
+            if len(os.listdir(capture_dir)) < 1:
+                # Don't return with a failure code unless we're
+                # running make. It could be normal to have captured
+                # nothing (eg, empty source file). Further output will
+                # alert the user that there was nothing to analyze.
+                if self.cmd[0] == 'make':
+                    # reuse code from gradle, etc. integration
+                    return util.run_compilation_commands([], 'make clean')
             return os.EX_OK
         except subprocess.CalledProcessError as exc:
             if self.args.debug:

infer/lib/python/inferlib/capture/mvn.py

@@ -61,4 +61,5 @@ class MavenCapture:
 
     def capture(self):
         cmds = self.get_infer_commands(util.get_build_output(self.build_cmd))
-        return util.run_commands(cmds)
+        clean_cmd = '%s clean' % self.build_cmd[0]
+        return util.run_compilation_commands(cmds, clean_cmd)

infer/lib/python/inferlib/capture/util.py

@@ -33,9 +33,13 @@ def get_build_output(build_cmd):
     return verbose_out_chars.split('\n')
 
 
-def run_commands(cmds):
+def run_compilation_commands(cmds, clean_cmd):
+    """runs compilation commands, and suggests a project cleaning command
+    in case there is nothing to compile.
+    """
     #  TODO call it in parallel
     if len(cmds) == 0:
+        print('Nothing to compile. Try running `%s` first.' % clean_cmd)
         return os.EX_NOINPUT
     for cmd in cmds:
         if cmd.start() != os.EX_OK: