feat: use FAKETIME_FMT environment var instead of patching libfaketime

.github/workflows/tests.yaml

@@ -36,7 +36,6 @@ jobs:
           key: pip|${{ hashFiles('setup.py') }}|${{ hashFiles('setup.cfg') }}
       - run: pip install tox
       - run: git submodule update --init --force
-      - run: git apply --directory libfaketime/vendor/libfaketime libfaketime/vendor/nanosecond.patch
       - run: env FAKETIME_COMPILE_CFLAGS="-UFAKE_STAT -UFAKE_UTIME -UFAKE_SLEEP" make -C libfaketime/vendor/libfaketime
         if: runner.os == 'Linux'
       - run: make -C libfaketime/vendor/libfaketime

README.md

@@ -165,7 +165,6 @@ Contributions are welcome! You should compile libfaketime before running tests:
 
 ```bash
 git submodule init --update
-git apply --directory libfaketime/vendor/libfaketime libfaketime/vendor/nanosecond.patch
 # For Linux:
 env FAKETIME_COMPILE_CFLAGS="-UFAKE_STAT -UFAKE_UTIME -UFAKE_SLEEP" make -C libfaketime/vendor/libfaketime
 # For macOS

libfaketime/__init__.py

@@ -26,7 +26,7 @@
 # This env var is set by reexec to ensure we don't reload more than once.
 
 _DID_REEXEC_VAR = 'FAKETIME_DID_REEXEC'
-
+_FAKETIME_FMT = '%Y-%m-%d %T.%f'
 
 def _get_lib_path():
     vendor_dir = 'libfaketime'
@@ -162,7 +162,7 @@ def _should_patch_uuid(self):
         return None
 
     def _format_datetime(self, _datetime):
-        return _datetime.strftime('%Y-%m-%d %T %f')
+        return _datetime.strftime(_FAKETIME_FMT)
 
     def tick(self, delta=datetime.timedelta(seconds=1)):
         self.time_to_freeze += delta
@@ -173,11 +173,13 @@ def __enter__(self):
             begin_callback(self)
             self._prev_spec = os.environ.get('FAKETIME')
             self._prev_tz = os.environ.get('TZ')
+            self._prev_fmt = os.environ.get('FAKETIME_FMT')
 
             os.environ['TZ'] = self.timezone_str
 
             time.tzset()
             os.environ['FAKETIME'] = self._format_datetime(self.time_to_freeze)
+            os.environ['FAKETIME_FMT'] = _FAKETIME_FMT
 
         func_name = self._should_patch_uuid()
         if func_name:
@@ -202,7 +204,13 @@ def __exit__(self, *exc):
                 os.environ['FAKETIME'] = self._prev_spec
             else:
                 del os.environ['FAKETIME']
-                end_callback(self)
+
+            if self._prev_fmt is not None:
+                os.environ['FAKETIME_FMT'] = self._prev_spec
+            else:
+                del os.environ['FAKETIME_FMT']
+
+            end_callback(self)
 
         return False
 

setup.py

@@ -38,7 +38,6 @@
 class CustomInstall(install):
     def run(self):
         self.my_outputs = []
-        subprocess.check_call(['patch', '-p1', '<', '../nanosecond.patch'], cwd=_vendor_path, shell=True)
         if sys.platform in ("linux", "linux2"):
             subprocess.check_call(['env', 'FAKETIME_COMPILE_CFLAGS=-UFAKE_STAT -UFAKE_UTIME -UFAKE_SLEEP', 'make', '-C', _vendor_path])
         elif sys.platform == "darwin":