Spyderlib Asynchronous Introspection Mockup

spyderlib_async_introspection.py

import threading


PLUGINS = ['jedi', 'rope', 'fallback']


def get_introspection(plugin, task):
    # TODO: make this a QThread
    name, source_code, offset, filename = task
    try:
        func = getattr(plugin, name)
        func(source_code, offset, filename)
    except Exception:
        print('send a qt signal back with the task and no result')
    else:
        print('send a qt signal back with the task and result')


class IntrospectionManager(object):

    def __init__(self, editor_widget):
        self.editor_widget = editor_widget
        self.plugins = self.get_plugins()
        self.incoming = []
        self.busy = False
        self.plugin_num = 0

    def get_completion_list(self, source_code, offset, filename):
        self.handle_task('get_completion_list', source_code, offset,
                         filename)

    def get_calltip_and_docs(self, source_code, offset, filename):
        self.handle_task('get_calltip_and_docs', source_code, offset,
                         filename)

    def get_definition_location(self, source_code, offset, filename):
        self.handle_task('get_definition_location', source_code, offset,
                         filename)

    @staticmethod
    def get_plugins():
        plugins = []
        for plugin_name in PLUGINS:
            mod_name = plugin_name + '_plugin'
            try:
                mod = __import__('spyderlib.utils.introspection.' + mod_name,
                                 fromlist=[mod_name])
                cls = getattr(mod, '%sPlugin' % plugin_name.capitalize())
                plugin = cls()
                plugin.load_plugin(self.editor_widget)
            except Exception:
                pass
            else:
                plugins.append(plugin)
        return plugins

    def handle_task(self, name, source_code, offset, filename):
        task = (name, source_code, offset, filename)
        if self.busy:
            self.incoming = task
            return
        plugin = self.plugins[self.plugin_num]
        thread = get_introspection(plugin, task)
        thread.setDaemon(True)
        thread.start()

    def handle_result(self, task, result):
        if self.incoming:
            incoming = self.incoming
            self.incoming = []
            self.handle_task(*incoming)
            return
        name, source_code, offset, filename = task
        if result is None:
            if self.plugin_num == len(self.plugins) - 1:
                self.busy = False
                return
            else:
                self.plugin_num += 1
                self.busy = False
                self.handle_task(task)
        else:
            self.plugin_num = 0
            self.handle_state(task, result)

    def handle_state(self, task, result):
        # TODO: get the current source_code, offset and filename
        # if we can use the data, do so