[doc] Add `unnecessary-lambda` example (#6844)

Signed-off-by: harupy <hkawamura0130@gmail.com>
Co-authored-by: Pierre Sassoulas <pierre.sassoulas@gmail.com>

3 files changed, 8 insertions, 2 deletions

diff --git a/doc/data/messages/u/unnecessary-lambda/bad.py b/doc/data/messages/u/unnecessary-lambda/bad.py
new file mode 100644
index 000000000..ddf84f7fa
--- /dev/null
+++ b/doc/data/messages/u/unnecessary-lambda/bad.py
@@ -0,0 +1,5 @@
+function = lambda x: print(x)  # [unnecessary-lambda]
+
+function("Hello world !")
+
+df.apply(lambda x: str(x))  # [unnecessary-lambda]
diff --git a/doc/data/messages/u/unnecessary-lambda/details.rst b/doc/data/messages/u/unnecessary-lambda/details.rst
deleted file mode 100644
index ab8204529..000000000
--- a/doc/data/messages/u/unnecessary-lambda/details.rst
+++ /dev/null
@@ -1 +0,0 @@
-You can help us make the doc better `by contributing <https://github.com/PyCQA/pylint/issues/5953>`_ !
diff --git a/doc/data/messages/u/unnecessary-lambda/good.py b/doc/data/messages/u/unnecessary-lambda/good.py
index c40beb573..9f0678f02 100644
--- a/doc/data/messages/u/unnecessary-lambda/good.py
+++ b/doc/data/messages/u/unnecessary-lambda/good.py
@@ -1 +1,3 @@
-# This is a placeholder for correct code for this message.
+print("Hello world !")
+
+df.apply(str)