Do not crash if next() is called without arguments (#7831)

Co-authored-by: Pierre Sassoulas <[email protected]> (cherry picked from commit a9c1cda)
pylint-dev · Nov 24, 2022 · 9ec1aa0 · 9ec1aa0
1 parent ac2da87
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diff --git a/doc/whatsnew/fragments/7828.bugfix b/doc/whatsnew/fragments/7828.bugfix
@@ -0,0 +1,3 @@
+Fixes a crash in ``stop-iteration-return`` when the ``next`` builtin is called without arguments.
+
+Closes #7828
diff --git a/pylint/checkers/refactoring/refactoring_checker.py b/pylint/checkers/refactoring/refactoring_checker.py
@@ -1134,6 +1134,11 @@ def _looks_like_infinite_iterator(param: nodes.NodeNG) -> bool:
             # A next() method, which is now what we want.
             return
 
+        if len(node.args) == 0:
+            # handle case when builtin.next is called without args.
+            # see https://github.com/PyCQA/pylint/issues/7828
+            return
+
         inferred = utils.safe_infer(node.func)
 
         if (

diff --git a/tests/functional/s/stop_iteration_inside_generator.py b/tests/functional/s/stop_iteration_inside_generator.py
@@ -175,3 +175,13 @@ def next(*things):
     it = iter(it)
     while True:
         yield next(1, 2)
+
+def data(filename):
+    """
+    Ensure pylint doesn't crash if `next` is incorrectly called without args
+    See https://github.com/PyCQA/pylint/issues/7828
+    """
+    with open(filename, encoding="utf8") as file:
+        next() # attempt to skip header but this is incorrect code
+        for line in file:
+            yield line
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,3 @@
		Fixes a crash in ``stop-iteration-return`` when the ``next`` builtin is called without arguments.

		Closes #7828