From 4c8cc1b9090fc315126a90b292b6ed17ac51deb1 Mon Sep 17 00:00:00 2001
From: FBruzzesi <francesco.bruzzesi.93@gmail.com>
Date: Sun, 10 Nov 2024 11:07:55 +0100
Subject: [PATCH] merge main, test invalid method

---
 narwhals/expr.py                   |  5 ++++-
 narwhals/series.py                 |  5 ++++-
 tests/expr_and_series/rank_test.py | 16 ++++++++++++++++
 3 files changed, 24 insertions(+), 2 deletions(-)

diff --git a/narwhals/expr.py b/narwhals/expr.py
index 089e56fcf..8c6fc8b27 100644
--- a/narwhals/expr.py
+++ b/narwhals/expr.py
@@ -2528,7 +2528,10 @@ def rank(
 
         supported_rank_methods = {"average", "min", "max", "dense", "ordinal"}
         if method not in supported_rank_methods:
-            msg = f"Ranking method must be one of {supported_rank_methods}. Found '{method}'"
+            msg = (
+                "Ranking method must be one of {'average', 'min', 'max', 'dense', 'ordinal'}. "
+                f"Found '{method}'"
+            )
             raise ValueError(msg)
 
         return self.__class__(
diff --git a/narwhals/series.py b/narwhals/series.py
index b49e2d093..5f5a27c9c 100644
--- a/narwhals/series.py
+++ b/narwhals/series.py
@@ -2731,7 +2731,10 @@ def rank(
         """
         supported_rank_methods = {"average", "min", "max", "dense", "ordinal"}
         if method not in supported_rank_methods:
-            msg = f"Ranking method must be one of {supported_rank_methods}. Found '{method}'"
+            msg = (
+                "Ranking method must be one of {'average', 'min', 'max', 'dense', 'ordinal'}. "
+                f"Found '{method}'"
+            )
             raise ValueError(msg)
 
         return self._from_compliant_series(
diff --git a/tests/expr_and_series/rank_test.py b/tests/expr_and_series/rank_test.py
index 695e4a37a..259bfbd5d 100644
--- a/tests/expr_and_series/rank_test.py
+++ b/tests/expr_and_series/rank_test.py
@@ -101,3 +101,19 @@ def test_rank_expr_in_over_context(
     result = df.select(nw.col("a").rank(method=method).over("b"))
     expected_data = {"a": expected_over[method]}
     assert_equal_data(result, expected_data)
+
+
+def test_invalid_method_raise(constructor: Constructor) -> None:
+    method = "invalid_method_name"
+    df = nw.from_native(constructor(data_float))
+
+    msg = (
+        "Ranking method must be one of {'average', 'min', 'max', 'dense', 'ordinal'}. "
+        f"Found '{method}'"
+    )
+
+    with pytest.raises(ValueError, match=msg):
+        df.select(nw.col("a").rank(method=method))  # type: ignore[arg-type]
+
+    with pytest.raises(ValueError, match=msg):
+        df.lazy().collect()["a"].rank(method=method)  # type: ignore[arg-type]