Change ``unbalanced-tuple-unpacking`` back to a warning.

It used to be a warning until a couple of years ago, after it was promoted to
an error. But the check might be suggesting the wrong thing in some cases,
for instance when checking against ``sys.argv`` which cannot be known at static
analysis time. Given it might rely on potential unknown data, it's best to
have it as a warning.

Close #2522

2 files changed, 12 insertions, 2 deletions

diff --git a/ChangeLog b/ChangeLog
index 5e27fcc82..0b30a87ff 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -7,6 +7,16 @@ What's New in Pylint 2.2?
 
 Release date: TBA
 
+   * Change ``unbalanced-tuple-unpacking`` back to a warning.
+
+     It used to be a warning until a couple of years ago, after it was promoted to
+     an error. But the check might be suggesting the wrong thing in some cases,
+     for instance when checking against ``sys.argv`` which cannot be known at static
+     analysis time. Given it might rely on potential unknown data, it's best to
+     have it as a warning.
+
+     Close #2522
+
    * Remove ``enumerate`` usage suggestion when defining ``__iter__`` (C0200)
 
      Close #2477
diff --git a/pylint/checkers/variables.py b/pylint/checkers/variables.py
index e9c7ccb23..bf6825644 100644
--- a/pylint/checkers/variables.py
+++ b/pylint/checkers/variables.py
@@ -376,13 +376,13 @@ MSGS = {
         "a list comprehension or a generator expression) is used outside "
         "the loop.",
     ),
-    "E0632": (
+    "W0632": (
         "Possible unbalanced tuple unpacking with "
         "sequence%s: "
         "left side has %d label(s), right side has %d value(s)",
         "unbalanced-tuple-unpacking",
         "Used when there is an unbalanced tuple unpacking in assignment",
-        {"old_names": [("W0632", "unbalanced-tuple-unpacking")]},
+        {"old_names": [("E0632", "unbalanced-tuple-unpacking")]},
     ),
     "E0633": (
         "Attempting to unpack a non-sequence%s",