diff --git a/IPython/config/application.py b/IPython/config/application.py
index ef97162b3..264d3793a 100644
--- a/IPython/config/application.py
+++ b/IPython/config/application.py
@@ -159,7 +159,7 @@ def _log_level_changed(self, name, old, new):
         help="The date format used by logging formatters for %(asctime)s"
     )
     def _log_datefmt_changed(self, name, old, new):
-        self._log_format_changed()
+        self._log_format_changed('log_format', self.log_format, self.log_format)
     
     log_format = Unicode("[%(name)s]%(highlevel)s %(message)s", config=True,
         help="The Logging format template",

`_log_format_changed()` missing 3 required positional arguments
In `IPython.config.application`, the `_log_datefmt_changed` handler calls `_log_format_changed` but does not pass it the required arguments. My guess would be that this is the correct implementation:

```
def _log_datefmt_changed(self, name, old, new):
    self._log_format_changed(name, self.log_format, self.log_format)
```

However I am not really sure what the `name` parameter is for, so I might be wrong.
diff --git a/IPython/config/tests/test_application.py b/IPython/config/tests/test_application.py
index a03d548c2..5da6a1306 100644
--- a/IPython/config/tests/test_application.py
+++ b/IPython/config/tests/test_application.py
@@ -80,6 +80,7 @@ def test_log(self):
         # trigger reconstruction of the log formatter
         app.log.handlers = [handler]
         app.log_format = "%(message)s"
+        app.log_datefmt = "%Y-%m-%d %H:%M"
         app.log.info("hello")
         nt.assert_in("hello", stream.getvalue())
 

pip install -e .[test]
parse_log_pytest
requirements.txt
pytest pytest-cov pytest-xdist pytest-mock pytest-asyncio
apt-get update apt-get install -y gcc
3.6
requirements.txt
pytest --no-header -rA --tb=line --color=no -p no:cacheprovider -W ignore::DeprecationWarning
attrs==22.2.0
certifi==2021.5.30
charset-normalizer==2.0.12
coverage==6.2
execnet==1.9.0
idna==3.10
importlib-metadata==4.8.3
iniconfig==1.1.1
-e git+https://github.com/ipython/ipython.git@2af39462d92d3834d5780a87f44d5e6cee7ecb81#egg=ipython
nose==1.3.7
packaging==21.3
pluggy==1.0.0
py==1.11.0
pyparsing==3.1.4
pytest==7.0.1
pytest-asyncio==0.16.0
pytest-cov==4.0.0
pytest-mock==3.6.1
pytest-xdist==3.0.2
requests==2.27.1
tomli==1.2.3
typing_extensions==4.1.1
urllib3==1.26.20
zipp==3.6.0

name: ipython
channels:
  - defaults
  - https://repo.anaconda.com/pkgs/main
  - https://repo.anaconda.com/pkgs/r
  - conda-forge
dependencies:
  - _libgcc_mutex=0.1=main
  - _openmp_mutex=5.1=1_gnu
  - ca-certificates=2025.2.25=h06a4308_0
  - certifi=2021.5.30=py36h06a4308_0
  - ld_impl_linux-64=2.40=h12ee557_0
  - libffi=3.3=he6710b0_2
  - libgcc-ng=11.2.0=h1234567_1
  - libgomp=11.2.0=h1234567_1
  - libstdcxx-ng=11.2.0=h1234567_1
  - ncurses=6.4=h6a678d5_0
  - openssl=1.1.1w=h7f8727e_0
  - pip=21.2.2=py36h06a4308_0
  - python=3.6.13=h12debd9_1
  - readline=8.2=h5eee18b_0
  - setuptools=58.0.4=py36h06a4308_0
  - sqlite=3.45.3=h5eee18b_0
  - tk=8.6.14=h39e8969_0
  - wheel=0.37.1=pyhd3eb1b0_0
  - xz=5.6.4=h5eee18b_1
  - zlib=1.2.13=h5eee18b_1
  - pip:
      - attrs==22.2.0
      - charset-normalizer==2.0.12
      - coverage==6.2
      - execnet==1.9.0
      - idna==3.10
      - importlib-metadata==4.8.3
      - iniconfig==1.1.1
      - nose==1.3.7
      - packaging==21.3
      - pluggy==1.0.0
      - py==1.11.0
      - pyparsing==3.1.4
      - pytest==7.0.1
      - pytest-asyncio==0.16.0
      - pytest-cov==4.0.0
      - pytest-mock==3.6.1
      - pytest-xdist==3.0.2
      - requests==2.27.1
      - tomli==1.2.3
      - typing-extensions==4.1.1
      - urllib3==1.26.20
      - zipp==3.6.0
prefix: /opt/conda/envs/ipython

IPython/config/tests/test_application.py::TestApplication::test_log
IPython/config/tests/test_application.py::TestApplication::test_aliases IPython/config/tests/test_application.py::TestApplication::test_basic IPython/config/tests/test_application.py::TestApplication::test_config IPython/config/tests/test_application.py::TestApplication::test_config_propagation IPython/config/tests/test_application.py::TestApplication::test_extra_args IPython/config/tests/test_application.py::TestApplication::test_flag_clobber IPython/config/tests/test_application.py::TestApplication::test_flags IPython/config/tests/test_application.py::TestApplication::test_flatten_aliases IPython/config/tests/test_application.py::TestApplication::test_flatten_flags IPython/config/tests/test_application.py::TestApplication::test_multi_file IPython/config/tests/test_application.py::TestApplication::test_unicode_argv
IPython/config/application.py
IPython/config/application.py