Initial commit

env/lib/python3.10/site-packages/wagtail/hooks.py

@@ -0,0 +1,115 @@
+from contextlib import ContextDecorator
+from operator import itemgetter
+
+from wagtail.utils.apps import get_app_submodules
+
+_hooks = {}
+
+
+def register(hook_name, fn=None, order=0):
+    """
+    Register hook for ``hook_name``. Can be used as a decorator::
+
+        @register('hook_name')
+        def my_hook(...):
+            pass
+
+    or as a function call::
+
+        def my_hook(...):
+            pass
+        register('hook_name', my_hook)
+    """
+
+    # Pretend to be a decorator if fn is not supplied
+    if fn is None:
+
+        def decorator(fn):
+            register(hook_name, fn, order=order)
+            return fn
+
+        return decorator
+
+    if hook_name not in _hooks:
+        _hooks[hook_name] = []
+    _hooks[hook_name].append((fn, order))
+
+
+class TemporaryHook(ContextDecorator):
+    def __init__(self, hooks, order):
+        self.hooks = hooks
+        self.order = order
+
+    def __enter__(self):
+        for hook_name, fn in self.hooks:
+            if hook_name not in _hooks:
+                _hooks[hook_name] = []
+            _hooks[hook_name].append((fn, self.order))
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        for hook_name, fn in self.hooks:
+            _hooks[hook_name].remove((fn, self.order))
+
+
+def register_temporarily(hook_name_or_hooks, fn=None, *, order=0):
+    """
+    Register hook for ``hook_name`` temporarily. This is useful for testing hooks.
+
+    Can be used as a decorator::
+
+        def my_hook(...):
+            pass
+
+        class TestMyHook(Testcase):
+            @hooks.register_temporarily('hook_name', my_hook)
+            def test_my_hook(self):
+                pass
+
+    or as a context manager::
+
+        def my_hook(...):
+            pass
+
+        with hooks.register_temporarily('hook_name', my_hook):
+            # Hook is registered here
+
+        # Hook is unregistered here
+
+    To register multiple hooks at the same time, pass in a list of 2-tuples:
+
+        def my_hook(...):
+            pass
+
+        def my_other_hook(...):
+            pass
+
+        with hooks.register_temporarily([
+                ('hook_name', my_hook),
+                ('hook_name', my_other_hook),
+            ]):
+            # Hooks are registered here
+    """
+    if not isinstance(hook_name_or_hooks, list) and fn is not None:
+        hooks = [(hook_name_or_hooks, fn)]
+    else:
+        hooks = hook_name_or_hooks
+
+    return TemporaryHook(hooks, order)
+
+
+_searched_for_hooks = False
+
+
+def search_for_hooks():
+    global _searched_for_hooks
+    if not _searched_for_hooks:
+        list(get_app_submodules("wagtail_hooks"))
+        _searched_for_hooks = True
+
+
+def get_hooks(hook_name):
+    """Return the hooks function sorted by their order."""
+    search_for_hooks()
+    hooks = _hooks.get(hook_name, [])
+    hooks = sorted(hooks, key=itemgetter(1))
+    return [hook[0] for hook in hooks]