Noissue - Fixed false positive A203 when using "yield from"

flake8-eyeo/flake8_eyeo.py

Index: flake8-eyeo/flake8_eyeo.py
===================================================================
--- a/flake8-eyeo/flake8_eyeo.py
+++ b/flake8-eyeo/flake8_eyeo.py
@@ -102,7 +102,13 @@
                 continue
             if docstring and i == 0 and isinstance(node.value, ast.Str):
                 continue
-            if isinstance(node.value, (ast.Call, ast.Yield)):
+
+            non_literal_expr_nodes = (ast.Call, ast.Yield)
+            try:
+                non_literal_expr_nodes += (ast.YieldFrom,)

[Sebastian Noack, 2017/11/29 21:51:37]

This change prevents and A203 to be (incorrectly) reported for code like this:

  def foo(x):
      yield from x

"yield from" was introduced in Python 3.3, hence the check here. Also I didn't
add a regression test, since we currently cannot have test cases that cause
syntax errors on some Python versions. :(

+            except AttributeError:
+                pass
+            if isinstance(node.value, non_literal_expr_nodes):
                 continue
 
             self.errors.append((node, 'A203 unused expression'))