Add support for -m and -c in interpreter mode. (#563)

This emulates the behavior of the python interpreter as we already do for
`-` and <file>.

Fixes #547

pex/pex.py

@@ -431,18 +431,29 @@ def demote_bootstrap(cls):
     TRACER.log('  * - paths that do not exist or will be imported via zipimport')
 
   def execute_interpreter(self):
-    if sys.argv[1:]:
-      program = sys.argv[1]
-      try:
-        if program == '-':
-          content = sys.stdin.read()
-        else:
-          with open(program) as fp:
-            content = fp.read()
-      except IOError as e:
-        die("Could not open %s in the environment [%s]: %s" % (program, sys.argv[0], e))
-      sys.argv = sys.argv[1:]
-      self.execute_content(program, content)
+    args = sys.argv[1:]
+    if args:
+      # NB: We take care here to setup sys.argv to match how CPython does it for each case.
+      arg = args[0]
+      if arg == '-c':
+        content = args[1]
+        sys.argv = ['-c'] + args[2:]
+        self.execute_content('-c <cmd>', content, argv0='-c')
+      elif arg == '-m':
+        module = args[1]
+        sys.argv = args[1:]
+        self.execute_module(module)
+      else:
+        try:
+          if arg == '-':
+            content = sys.stdin.read()
+          else:
+            with open(arg) as fp:
+              content = fp.read()
+        except IOError as e:
+          die("Could not open %s in the environment [%s]: %s" % (arg, sys.argv[0], e))
+        sys.argv = args
+        self.execute_content(arg, content)
     else:
       self.demote_bootstrap()
 

tests/test_pex.py

@@ -347,6 +347,40 @@ def test_activate_interpreter_different_from_current():
           pytest.fail('PEX activation of %s failed with %s' % (pex, e))
 
 
+def test_execute_interpreter_dashc_program():
+  with temporary_dir() as pex_chroot:
+    pex_builder = PEXBuilder(path=pex_chroot)
+    pex_builder.freeze()
+    process = PEX(pex_chroot).run(args=['-c', 'import sys; print(" ".join(sys.argv))', 'one'],
+                                  stdout=subprocess.PIPE,
+                                  stderr=subprocess.PIPE,
+                                  blocking=False)
+    stdout, stderr = process.communicate()
+
+    assert 0 == process.returncode
+    assert b'-c one\n' == stdout
+    assert b'' == stderr
+
+
+def test_execute_interpreter_dashm_module():
+  with temporary_dir() as pex_chroot:
+    pex_builder = PEXBuilder(path=pex_chroot)
+    with temporary_file(root_dir=pex_chroot) as fp:
+      fp.write(b'import sys; print(" ".join(sys.argv))')
+      fp.close()
+      pex_builder.add_source(fp.name, 'foo/bar.py')
+    pex_builder.freeze()
+    process = PEX(pex_chroot).run(args=['-m', 'foo.bar', 'one', 'two'],
+                                  stdout=subprocess.PIPE,
+                                  stderr=subprocess.PIPE,
+                                  blocking=False)
+    stdout, stderr = process.communicate()
+
+    assert 0 == process.returncode
+    assert b'foo.bar one two\n' == stdout
+    assert b'' == stderr
+
+
 def test_execute_interpreter_stdin_program():
   with temporary_dir() as pex_chroot:
     pex_builder = PEXBuilder(path=pex_chroot)
@@ -356,13 +390,31 @@ def test_execute_interpreter_stdin_program():
                                   stderr=subprocess.PIPE,
                                   stdin=subprocess.PIPE,
                                   blocking=False)
-    stdout, stderr = process.communicate(input=b'import sys; print(" ".join(sys.argv[1:]))')
+    stdout, stderr = process.communicate(input=b'import sys; print(" ".join(sys.argv))')
 
     assert 0 == process.returncode
-    assert b'one two\n' == stdout
+    assert b'- one two\n' == stdout
     assert b'' == stderr
 
 
+def test_execute_interpreter_file_program():
+  with temporary_dir() as pex_chroot:
+    pex_builder = PEXBuilder(path=pex_chroot)
+    pex_builder.freeze()
+    with temporary_file(root_dir=pex_chroot) as fp:
+      fp.write(b'import sys; print(" ".join(sys.argv))')
+      fp.close()
+      process = PEX(pex_chroot).run(args=[fp.name, 'one', 'two'],
+                                    stdout=subprocess.PIPE,
+                                    stderr=subprocess.PIPE,
+                                    blocking=False)
+      stdout, stderr = process.communicate()
+
+      assert 0 == process.returncode
+      assert '{} one two\n'.format(fp.name).encode('utf-8') == stdout
+      assert b'' == stderr
+
+
 def test_pex_run_custom_setuptools_useable():
   with temporary_dir() as resolve_cache:
     dists = resolve(['setuptools==36.2.7'], cache=resolve_cache)