Fix custom importlib code for Python < 3.5

wbond · Aug 22, 2023 · e813e83 · e813e83
1 parent 6eeaba0
commit e813e83
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Showing 2 changed files with 101 additions and 48 deletions.
diff --git a/dev/_import.py b/dev/_import.py
@@ -20,44 +20,44 @@
     getcwd = os.getcwd
 
 
-class ModCryptoMetaFinder(importlib.abc.MetaPathFinder):
-    def setup(self):
-        self.modules = {}
-        sys.meta_path.insert(0, self)
-
-    def add_module(self, package_name, package_path):
-        if package_name not in self.modules:
-            self.modules[package_name] = package_path
-
-    def find_spec(self, fullname, path, target=None):
-        name_parts = fullname.split('.')
-        if name_parts[0] not in self.modules:
-            return None
-
-        package = name_parts[0]
-        package_path = self.modules[package]
-
-        fullpath = os.path.join(package_path, *name_parts[1:])
-
-        if os.path.isdir(fullpath):
-            filename = os.path.join(fullpath, "__init__.py")
-            submodule_locations = [fullpath]
-        else:
-            filename = fullpath + ".py"
-            submodule_locations = None
-
-        if not os.path.exists(filename):
-            return None
-
-        return importlib.util.spec_from_file_location(
-            fullname,
-            filename,
-            loader=None,
-            submodule_search_locations=submodule_locations
-        )
+if sys.version_info >= (3, 5):
+    class ModCryptoMetaFinder(importlib.abc.MetaPathFinder):
+        def setup(self):
+            self.modules = {}
+            sys.meta_path.insert(0, self)
+
+        def add_module(self, package_name, package_path):
+            if package_name not in self.modules:
+                self.modules[package_name] = package_path
+
+        def find_spec(self, fullname, path, target=None):
+            name_parts = fullname.split('.')
+            if name_parts[0] not in self.modules:
+                return None
+
+            package = name_parts[0]
+            package_path = self.modules[package]
+
+            fullpath = os.path.join(package_path, *name_parts[1:])
+
+            if os.path.isdir(fullpath):
+                filename = os.path.join(fullpath, "__init__.py")
+                submodule_locations = [fullpath]
+            else:
+                filename = fullpath + ".py"
+                submodule_locations = None
+
+            if not os.path.exists(filename):
+                return None
+
+            return importlib.util.spec_from_file_location(
+                fullname,
+                filename,
+                loader=None,
+                submodule_search_locations=submodule_locations
+            )
 
 
-if sys.version_info >= (3, 5):
     CUSTOM_FINDER = ModCryptoMetaFinder()
     CUSTOM_FINDER.setup()
 

diff --git a/tests/__init__.py b/tests/__init__.py
@@ -17,6 +17,48 @@
 __version_info__ = (1, 5, 1)
 
 
+if sys.version_info >= (3, 5):
+    class ModCryptoMetaFinder(importlib.abc.MetaPathFinder):
+        def setup(self):
+            self.modules = {}
+            sys.meta_path.insert(0, self)
+
+        def add_module(self, package_name, package_path):
+            if package_name not in self.modules:
+                self.modules[package_name] = package_path
+
+        def find_spec(self, fullname, path, target=None):
+            name_parts = fullname.split('.')
+            if name_parts[0] not in self.modules:
+                return None
+
+            package = name_parts[0]
+            package_path = self.modules[package]
+
+            fullpath = os.path.join(package_path, *name_parts[1:])
+
+            if os.path.isdir(fullpath):
+                filename = os.path.join(fullpath, "__init__.py")
+                submodule_locations = [fullpath]
+            else:
+                filename = fullpath + ".py"
+                submodule_locations = None
+
+            if not os.path.exists(filename):
+                return None
+
+            return importlib.util.spec_from_file_location(
+                fullname,
+                filename,
+                loader=None,
+                submodule_search_locations=submodule_locations
+            )
+
+
+    CUSTOM_FINDER = ModCryptoMetaFinder()
+    CUSTOM_FINDER.setup()
+
+
 def _import_from(mod, path, mod_dir=None):
     """
     Imports a module from a specific path
@@ -39,29 +81,40 @@ def _import_from(mod, path, mod_dir=None):
         return sys.modules[mod]
 
     if mod_dir is None:
-        mod_dir = mod
+        full_mod = mod
+    else:
+        full_mod = mod_dir.replace(os.sep, '.')
+
+    if mod_dir is None:
+        mod_dir = mod.replace('.', os.sep)
 
     if not os.path.exists(path):
         return None
 
-    if not os.path.exists(os.path.join(path, mod_dir)):
+    source_path = os.path.join(path, mod_dir, '__init__.py')
+    if not os.path.exists(source_path):
+        source_path = os.path.join(path, mod_dir + '.py')
+
+    if not os.path.exists(source_path):
         return None
 
+    if os.sep in mod_dir:
+        append, mod_dir = mod_dir.rsplit(os.sep, 1)
+        path = os.path.join(path, append)
+
     try:
         if sys.version_info < (3, 5):
             mod_info = imp.find_module(mod_dir, [path])
             return imp.load_module(mod, *mod_info)
+
         else:
-            loader_details = (
-                importlib.machinery.SourceFileLoader,
-                importlib.machinery.SOURCE_SUFFIXES
-            )
-            finder = importlib.machinery.FileFinder(path, loader_details)
-            spec = finder.find_spec(mod_dir)
-            module = importlib.util.module_from_spec(spec)
-            sys.modules[mod] = module
-            spec.loader.exec_module(module)
-            return module
+            package = mod.split('.', 1)[0]
+            package_dir = full_mod.split('.', 1)[0]
+            package_path = os.path.join(path, package_dir)
+            CUSTOM_FINDER.add_module(package, package_path)
+
+            return importlib.import_module(mod)
+
     except ImportError:
         return None