Merge pull request #270 from aktech/py-file-debug

Add support for `py --debug` with file input

lib/python/pyflyby/_dbg.py

@@ -457,7 +457,7 @@ def debugger(*args, **kwargs):
       forked child.
     '''
     from ._parse import PythonStatement, PythonBlock, FileText
-    if len(args) == 1:
+    if len(args) in {1, 2}:
         arg = args[0]
     elif len(args) == 0:
         arg = None

tests/test_cmdline.py

@@ -681,3 +681,24 @@ def test_tidy_imports_symlinks_bad_argument():
     assert b"error: --symlinks must be one of" in proc_output
     assert output == input
     assert symlink_output == input
+
+def test_debug_filetype_with_py():
+    with tempfile.NamedTemporaryFile(suffix=".py", mode='w+') as f:
+        f.write(dedent("""
+            sys.argv
+        """).lstrip())
+        f.flush()
+        command = [BIN_DIR+"/py", "--debug", f.name]
+
+        output_result = b""
+        child = pexpect.spawn(' '.join(command), timeout=5)
+        child.expect('ipdb>')
+        output_result += child.before
+        child.sendline('c')
+        output_result += child.before
+        child.expect(pexpect.EOF)
+        output_result += child.before
+
+        expected = "Entering debugger.  Use 'n' to step, 'c' to run, 'q' to stop."
+        assert expected in output_result.decode()
+