core: move split compat/legacy modules into hpi_compat and compat

my/core/compat.py

@@ -1,56 +1,12 @@
 '''
-Some backwards compatibility stuff/deprecation helpers
+Contains backwards compatibility helpers for different python versions.
+If something is relevant to HPI itself, please put it in .hpi_compat instead
 '''
+import os
 import sys
-from types import ModuleType
 from typing import TYPE_CHECKING
 
-from . import warnings
-from .common import LazyLogger
 
-
-logger = LazyLogger('my.core.compat')
-
-
-def pre_pip_dal_handler(
-        name: str,
-        e: ModuleNotFoundError,
-        cfg,
-        requires=[],
-) -> ModuleType:
-    '''
-    https://github.com/karlicoss/HPI/issues/79
-    '''
-    if e.name != name:
-        # the module itself was imported, so the problem is with some dependencies
-        raise e
-    try:
-        dal = _get_dal(cfg, name)
-        warnings.high(f'''
-Specifying modules' dependencies in the config or in my/config/repos is deprecated!
-Please install {' '.join(requires)} as PIP packages (see the corresponding README instructions).
-'''.strip(), stacklevel=2)
-    except ModuleNotFoundError:
-        dal = None
-
-    if dal is None:
-        # probably means there was nothing in the old config in the first place
-        # so we should raise the original exception
-        raise e
-    return dal
-
-
-def _get_dal(cfg, module_name: str):
-    mpath = getattr(cfg, module_name, None)
-    if mpath is not None:
-        from .common import import_dir
-        return import_dir(mpath, '.dal')
-    else:
-        from importlib import import_module
-        return import_module(f'my.config.repos.{module_name}.dal')
-
-
-import os
 windows = os.name == 'nt'
 
 
@@ -60,7 +16,7 @@ def sqlite_backup(*, source: sqlite3.Connection, dest: sqlite3.Connection, **kwa
     source.backup(dest, **kwargs)
 
 
-# can remove after python3.9
+# can remove after python3.9 (although need to keep the method itself for bwd compat)
 def removeprefix(text: str, prefix: str) -> str:
     if text.startswith(prefix):
         return text[len(prefix):]