From 07155cfa5302b78140e2bad5ac55ca8e6ed59752 Mon Sep 17 00:00:00 2001
From: = <=>
Date: Tue, 5 Nov 2024 15:17:08 +0100
Subject: [PATCH] fix : strict parameter is enabled by default

---
 py-polars/polars/expr/struct.py   | 10 +++++++---
 py-polars/polars/series/struct.py | 13 +++++++------
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/py-polars/polars/expr/struct.py b/py-polars/polars/expr/struct.py
index 1df3a16f4411..2ee60c0f39bf 100644
--- a/py-polars/polars/expr/struct.py
+++ b/py-polars/polars/expr/struct.py
@@ -189,7 +189,7 @@ def unnest(self) -> Expr:
         """
         return self.field("*")
 
-    def rename_fields(self, names: Sequence[str]) -> Expr:
+    def rename_fields(self, names: Sequence[str], strict: bool = True) -> Expr:
         """
         Rename the fields of the struct.
 
@@ -197,6 +197,8 @@ def rename_fields(self, names: Sequence[str]) -> Expr:
         ----------
         names
             New names, given in the same order as the struct's fields.
+        strict
+            If True, raises an error if the length of names does not match the number of fields.
 
         Examples
         --------
@@ -214,7 +216,7 @@ def rename_fields(self, names: Sequence[str]) -> Expr:
         │ struct_col           │
         │ ---                  │
         │ struct[4]            │
-        ╞══════════════════════╡
+        ╞══════��═══════════════╡
         │ {1,"ab",true,[1, 2]} │
         │ {2,"cd",null,[3]}    │
         └──────────────────────┘
@@ -251,6 +253,8 @@ def rename_fields(self, names: Sequence[str]) -> Expr:
         >>> df.select(pl.col("struct_col").struct.field("aaa"))  # doctest: +SKIP
         StructFieldNotFoundError: aaa
         """
+        if strict and len(names) != len(self.fields):
+            raise ValueError("The length of names must match the number of fields in the struct.")
         return wrap_expr(self._pyexpr.struct_rename_fields(names))
 
     def json_encode(self) -> Expr:
@@ -332,7 +336,7 @@ def with_fields(
         │ 1.0 ┆ 4   ┆ 40    ┆ 10       │
         │ 2.0 ┆ 9   ┆ 18    ┆ 2        │
         │ 3.0 ┆ 16  ┆ 48    ┆ 3        │
-        └─────┴─────┴───────┴──────────┘
+        └─────┴─────┴──���────┴───���──────┘
 
         Parameters
         ----------
diff --git a/py-polars/polars/series/struct.py b/py-polars/polars/series/struct.py
index a04d254808d3..8b89f631f610 100644
--- a/py-polars/polars/series/struct.py
+++ b/py-polars/polars/series/struct.py
@@ -73,7 +73,7 @@ def field(self, name: str) -> Series:
         ]
         """
 
-    def rename_fields(self, names: Sequence[str]) -> Series:
+    def rename_fields(self, names: Sequence[str], strict: bool = True) -> Series:
         """
         Rename the fields of the struct.
 
@@ -81,16 +81,17 @@ def rename_fields(self, names: Sequence[str]) -> Series:
         ----------
         names
             New names in the order of the struct's fields.
+        strict
+            If True, raises an error if the length of names does not match the number of fields.
 
         Examples
         --------
         >>> s = pl.Series([{"a": 1, "b": 2}, {"a": 3, "b": 4}])
-        >>> s.struct.fields
-        ['a', 'b']
-        >>> s = s.struct.rename_fields(["c", "d"])
-        >>> s.struct.fields
-        ['c', 'd']
+        >>> s.struct.rename_fields(["c", "d"], strict=True)
         """
+        if strict and len(names) != len(self.fields):
+            raise ValueError("The length of names must match the number of fields in the struct.")
+        
 
     @property
     def schema(self) -> Schema: