raise error in safe_eval instead of returning sentinal

thomasballinger · thomasballinger · commit dbf40e79e704 · 2014-10-08T14:42:53.000-04:00
diff --git a/bpython/autocomplete.py b/bpython/autocomplete.py
@@ -205,8 +205,10 @@ def matches(cls, cursor_offset, line, locals_, **kwargs):
             return None
         start, end, orig = r
         _, _, dexpr = lineparts.current_dict(cursor_offset, line)
-        obj = safe_eval(dexpr, locals_)
-        if obj is SafeEvalFailed:
+
+        try:
+            obj = safe_eval(dexpr, locals_)
+        except EvaluationError:
             return []
         if obj and isinstance(obj, type({})) and obj.keys():
             return ["{!r}]".format(k) for k in obj.keys() if repr(k).startswith(orig)]
@@ -328,23 +330,17 @@ def matches(cls, cursor_offset, line, **kwargs):
             return [match for match in matches if not match.startswith('_')]
         return matches
 
-class SafeEvalFailed(Exception):
-    """If this object is returned, safe_eval failed"""
-    # Because every normal Python value is a possible return value of safe_eval
+class EvaluationError(Exception):
+    """safe_eval failed"""
 
 def safe_eval(expr, namespace):
     """Not all that safe, just catches some errors"""
-    if expr.isdigit():
-        # Special case: float literal, using attrs here will result in
-        # a SyntaxError
-        return SafeEvalFailed
     try:
-        obj = eval(expr, namespace)
-        return obj
-    except (NameError, AttributeError, SyntaxError) as e:
-        # If debugging safe_eval, raise this!
-        # raise e
-        return SafeEvalFailed
+        return eval(expr, namespace)
+    except (NameError, AttributeError, SyntaxError):
+        # If debugging safe_eval, reraise!
+        # raise
+        raise EvaluationError
 
 def attr_matches(text, namespace, autocomplete_mode):
     """Taken from rlcompleter.py and bent to my will.
@@ -358,8 +354,13 @@ def attr_matches(text, namespace, autocomplete_mode):
         return []
 
     expr, attr = m.group(1, 3)
-    obj = safe_eval(expr, namespace)
-    if obj is SafeEvalFailed:
+    if expr.isdigit():
+        # Special case: float literal, using attrs here will result in
+        # a SyntaxError
+        return []
+    try:
+        obj = safe_eval(expr, namespace)
+    except EvaluationError:
         return []
     with inspection.AttrCleaner(obj):
         matches = attr_lookup(obj, expr, attr, autocomplete_mode)
diff --git a/bpython/test/test_autocomplete.py b/bpython/test/test_autocomplete.py
@@ -18,8 +18,10 @@ class TestSafeEval(unittest.TestCase):
     def test_catches_syntax_error(self):
         try:
             autocomplete.safe_eval('1re',{})
-        except:
+        except SyntaxError:
             self.fail('safe_eval raises an error')
+        except autocomplete.EvaluationError as e:
+            pass
 
 class TestFormatters(unittest.TestCase):
 
