gh-159672: Restore flags support in codeop.compile_command

Author: pablogsal

Lib/codeop.py

@@ -47,7 +47,7 @@
 PyCF_ONLY_AST = 0x400
 PyCF_ALLOW_INCOMPLETE_INPUT = 0x4000
 
-def _maybe_compile(compiler, source, filename, symbol):
+def _maybe_compile(compiler, source, filename, symbol, flags):
     # Check for source consisting of only blank lines and comments.
     for line in source.split("\n"):
         line = line.strip()
@@ -61,22 +61,21 @@ def _maybe_compile(compiler, source, filename, symbol):
     with warnings.catch_warnings():
         warnings.simplefilter("ignore", (SyntaxWarning, DeprecationWarning))
         try:
-            compiler(source, filename, symbol)
+            compiler(source, filename, symbol, flags=flags)
         except _IncompleteInputError:
             return None
         except SyntaxError:  # Let other compile() errors propagate.
             pass
 
     return compiler(source, filename, symbol, incomplete_input=False)
 
-def _compile(source, filename, symbol, incomplete_input=True):
-    flags = 0
+def _compile(source, filename, symbol, incomplete_input=True, *, flags=0):
     if incomplete_input:
         flags |= PyCF_ALLOW_INCOMPLETE_INPUT
         flags |= PyCF_DONT_IMPLY_DEDENT
     return compile(source, filename, symbol, flags)
 
-def compile_command(source, filename="<input>", symbol="single"):
+def compile_command(source, filename="<input>", symbol="single", flags=0):
     r"""Compile a command and determine whether it is incomplete.
 
     Arguments:
@@ -95,7 +94,7 @@ def compile_command(source, filename="<input>", symbol="single"):
       syntax error (OverflowError and ValueError can be produced by
       malformed literals).
     """
-    return _maybe_compile(_compile, source, filename, symbol)
+    return _maybe_compile(_compile, source, filename, symbol, flags)
 
 class Compile:
     """Instances of this class behave much like the built-in compile
@@ -147,4 +146,4 @@ def __call__(self, source, filename="<input>", symbol="single"):
           syntax error (OverflowError and ValueError can be produced by
           malformed literals).
         """
-        return _maybe_compile(self.compiler, source, filename, symbol)
+        return _maybe_compile(self.compiler, source, filename, symbol, flags=self.compiler.flags)

Lib/test/test_codeop.py

@@ -19,6 +19,19 @@
 
 
 class CodeopTests(unittest.TestCase):
+    def test_compile_command_flags(self):
+        import __future__
+
+        source = "x = 1"
+        expected = compile(source, "<input>", "single")
+        self.assertEqual(compile_command(source, "<input>", "single", 0), expected)
+        self.assertEqual(compile_command(source, flags=0), expected)
+
+        flags = __future__.barry_as_FLUFL.compiler_flag
+        source = "if 1 <> 2:\n"
+        self.assertIsNone(compile_command(source, "<input>", "single", flags))
+        self.assertIsNone(compile_command(source, flags=flags))
+
     def assertValid(self, str, symbol='single', *, compiler):
         '''succeed iff str is a valid piece of code'''
         expected = compile(str, "<input>", symbol, PyCF_DONT_IMPLY_DEDENT)