import os
from collections import defaultdict
from .. import importcompletion
try:
from watchdog.observers import Observer
from watchdog.events import FileSystemEventHandler
except ImportError:
def ModuleChangedEventHandler(*args):
return None
else:
class ModuleChangedEventHandler(FileSystemEventHandler): # type: ignore [no-redef]
def __init__(self, paths, on_change):
self.dirs = defaultdict(set)
self.on_change = on_change
self.modules_to_add_later = []
self.observer = Observer()
self.old_dirs = defaultdict(set)
self.started = False
self.activated = False
for path in paths:
self._add_module(path)
super().__init__()
def reset(self):
self.dirs = defaultdict(set)
del self.modules_to_add_later[:]
self.old_dirs = defaultdict(set)
self.observer.unschedule_all()
def _add_module(self, path):
"""Add a python module to track changes"""
path = os.path.abspath(path)
for suff in importcompletion.SUFFIXES:
if path.endswith(suff):
path = path[: -len(suff)]
break
dirname = os.path.dirname(path)
if dirname not in self.dirs:
self.observer.schedule(self, dirname, recursive=False)
self.dirs[dirname].add(path)
def _add_module_later(self, path):
self.modules_to_add_later.append(path)
def track_module(self, path):
"""
Begins tracking this if activated, or remembers to track later.
"""
if self.activated:
self._add_module(path)
else:
self._add_module_later(path)
def activate(self):
if self.activated:
raise ValueError(f"{self!r} is already activated.")
if not self.started:
self.started = True
self.observer.start()
for dirname in self.dirs:
self.observer.schedule(self, dirname, recursive=False)
for module in self.modules_to_add_later:
self._add_module(module)
del self.modules_to_add_later[:]
self.activated = True
def deactivate(self):
if not self.activated:
raise ValueError(f"{self!r} is not activated.")
self.observer.unschedule_all()
self.activated = False
def on_any_event(self, event):
dirpath = os.path.dirname(event.src_path)
paths = [path + ".py" for path in self.dirs[dirpath]]
if event.src_path in paths:
self.on_change(files_modified=[event.src_path])