autotrigger: solve performance issues

pythonx/UltiSnips/snippet/source/_base.py

@@ -16,7 +16,7 @@ class SnippetSource(object):
         self._snippets = defaultdict(SnippetDictionary)
         self._extends = defaultdict(set)
 
-    def ensure(self, filetypes):
+    def ensure(self, filetypes, cached):
         """Update/reload the snippets in the source when needed.
 
         It makes sure that the snippets are not outdated.

pythonx/UltiSnips/snippet/source/file/_base.py

@@ -36,12 +36,18 @@ class SnippetFileSource(SnippetSource):
         SnippetSource.__init__(self)
         self._files_for_ft = defaultdict(set)
         self._file_hashes = defaultdict(lambda: None)
+        self._ensure_cached = False
+
+    def ensure(self, filetypes, cached):
+        if cached and self._ensure_cached:
+            return
 
-    def ensure(self, filetypes):
         for ft in self.get_deep_extends(filetypes):
             if self._needs_update(ft):
                 self._load_snippets_for(ft)
 
+        self._ensure_cached = True
+
     def _get_all_snippet_files_for(self, ft):
         """Returns a set of all files that define snippets for 'ft'."""
         raise NotImplementedError()

pythonx/UltiSnips/snippet_manager.py

@@ -554,8 +554,7 @@ class SnippetManager(object):
         clear_priority = None
         cleared = {}
         for _, source in self._snippet_sources:
-            if not autotrigger_only or not source.loaded(filetypes):
-                source.ensure(filetypes)
+            source.ensure(filetypes, cached=autotrigger_only)
 
         # Collect cleared information from sources.
         for _, source in self._snippet_sources: