bpo-40067: Improve error messages for multiple star expressions in assignments (GH-19168)

furkanonder · isidentical · pablogsal · web-flow · commit cb6534e1a883 · 2020-03-26T01:54:31.000Z
Co-Authored-By: Batuhan Taşkaya &lt;isidentical@gmail.com&gt;
Co-Authored-By: Pablo Galindo &lt;Pablogsal@gmail.com&gt;
diff --git a/Lib/test/test_unpack_ex.py b/Lib/test/test_unpack_ex.py
@@ -308,12 +308,17 @@
     >>> a, *b, c, *d, e = range(10) # doctest:+ELLIPSIS
     Traceback (most recent call last):
       ...
-    SyntaxError: two starred expressions in assignment
+    SyntaxError: multiple starred expressions in assignment
 
     >>> [*b, *c] = range(10) # doctest:+ELLIPSIS
     Traceback (most recent call last):
       ...
-    SyntaxError: two starred expressions in assignment
+    SyntaxError: multiple starred expressions in assignment
+
+    >>> a,*b,*c,*d = range(4) # doctest:+ELLIPSIS
+    Traceback (most recent call last):
+      ...
+    SyntaxError: multiple starred expressions in assignment
 
     >>> *a = range(10) # doctest:+ELLIPSIS
     Traceback (most recent call last):
diff --git a/Misc/ACKS b/Misc/ACKS
@@ -1236,6 +1236,7 @@ Jeffrey Ollie
 Adam Olsen
 Bryan Olson
 Grant Olson
+Furkan Onder
 Koray Oner
 Piet van Oostrum
 Tomas Oppelstrup
diff --git a/Misc/NEWS.d/next/Core and Builtins/2020-03-25-20-34-01.bpo-40067.0bFda2.rst b/Misc/NEWS.d/next/Core and Builtins/2020-03-25-20-34-01.bpo-40067.0bFda2.rst
@@ -0,0 +1,2 @@
+Improve the error message for multiple star expressions in an assignment.
+Patch by Furkan Onder
diff --git a/Python/compile.c b/Python/compile.c
@@ -3708,7 +3708,7 @@ assignment_helper(struct compiler *c, asdl_seq *elts)
         }
         else if (elt->kind == Starred_kind) {
             return compiler_error(c,
-                "two starred expressions in assignment");
+                "multiple starred expressions in assignment");
         }
     }
     if (!seen_star) {

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,2 @@`
	`1`	`+Improve the error message for multiple star expressions in an assignment.`
	`2`	`+Patch by Furkan Onder`
Original file line number	Diff line number	Diff line change
`@@ -3708,7 +3708,7 @@ assignment_helper(struct compiler c, asdl_seq elts)`
`3708`	`3708`	`}`
`3709`	`3709`	`else if (elt->kind == Starred_kind) {`
`3710`	`3710`	`return compiler_error(c,`
`3711`		`- "two starred expressions in assignment");`
	`3711`	`+ "multiple starred expressions in assignment");`
`3712`	`3712`	`}`
`3713`	`3713`	`}`
`3714`	`3714`	`if (!seen_star) {`