[3.9] bpo-40334: Produce better error messages on invalid targets (GH-20106) (GH-20973)
* bpo-40334: Produce better error messages on invalid targets (GH-20106)
The following error messages get produced:
- `cannot delete ...` for invalid `del` targets
- `... is an illegal 'for' target` for invalid targets in for
statements
- `... is an illegal 'with' target` for invalid targets in
with statements
Additionally, a few `cut`s were added in various places before the
invocation of the `invalid_*` rule, in order to speed things
up.
Co-authored-by: Pablo Galindo <Pablogsal@gmail.com>
(cherry picked from commit 01ece63d42b830df106948db0aefa6c1ba24416a)
diff --git a/Lib/test/test_exceptions.py b/Lib/test/test_exceptions.py
index 196f31e..0741bb1 100644
--- a/Lib/test/test_exceptions.py
+++ b/Lib/test/test_exceptions.py
@@ -253,7 +253,7 @@
check('foo(x for x in range(10), 100)', 1, 5)
check('(yield i) = 2', 1, 1 if support.use_old_parser() else 2)
check('def f(*):\n pass', 1, 7 if support.use_old_parser() else 8)
- check('for 1 in []: pass', 1, 5 if support.use_old_parser() else 7)
+ check('for 1 in []: pass', 1, 5)
@cpython_only
def testSettingException(self):
diff --git a/Lib/test/test_syntax.py b/Lib/test/test_syntax.py
index 1d10a20..b231f1c 100644
--- a/Lib/test/test_syntax.py
+++ b/Lib/test/test_syntax.py
@@ -160,6 +160,61 @@
Traceback (most recent call last):
SyntaxError: 'list' is an illegal expression for augmented assignment
+Invalid targets in `for` loops and `with` statements should also
+produce a specialized error message
+
+>>> for a() in b: pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> for (a, b()) in b: pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> for [a, b()] in b: pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> for (*a, b, c+1) in b: pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to operator
+
+>>> for (x, *(y, z.d())) in b: pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> for a, b() in c: pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> for i < (): pass
+Traceback (most recent call last):
+SyntaxError: invalid syntax
+
+>>> with a as b(): pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> with a as (b, c()): pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> with a as [b, c()]: pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> with a as (*b, c, d+1): pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to operator
+
+>>> with a as (x, *(y, z.d())): pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
+>>> with a as b, c as d(): pass
+Traceback (most recent call last):
+SyntaxError: cannot assign to function call
+
>>> p = p =
Traceback (most recent call last):
SyntaxError: invalid syntax
@@ -736,7 +791,7 @@
self._check_error("del (1, 2)", "delete literal")
self._check_error("del None", "delete None")
self._check_error("del *x", "delete starred")
- self._check_error("del (*x)", "delete starred")
+ self._check_error("del (*x)", "use starred expression")
self._check_error("del (*x,)", "delete starred")
self._check_error("del [*x,]", "delete starred")
self._check_error("del f()", "delete function call")