Simplify expansion condition and handle show_snippets = "all" correctly

autoload/cmp_nvim_ultisnips.vim

@@ -5,7 +5,7 @@
 " per snippet) with the keys "trigger", "description", "options" and "value".
 "
 " If 'expandable_only' is "True", only expandable snippets are returned, otherwise all
-" snippets for the current filetype are returned.
+" snippets except regex and custom context snippets for the current filetype are returned.
 function! cmp_nvim_ultisnips#get_current_snippets(expandable_only)
 let g:_cmpu_current_snippets = []
 python3 << EOF
@@ -22,10 +22,13 @@ else:
 
 for snippet in snippets:
     is_context_snippet = snippet._context_code != None
-    # For custom context snippets, we need to check if the snippet is in the right context to be expanded
-    is_expandable = not expandable_only or not is_context_snippet or snippet._context_match(visual_content, before)
-    if not is_expandable:
+    is_regex_snippet = "r" in snippet._opts
+    # If show_snippets == "all", the snippets are cached so ignore "dynamic" snippets.
+    if not expandable_only and (is_context_snippet or is_regex_snippet):
       continue
+    # For custom context snippets, always check if the context matches.
+    if is_context_snippet and not snippet._context_match(visual_content, before):
+        continue
 
     vim.command(
       "call add(g:_cmpu_current_snippets, {"

lua/cmp_nvim_ultisnips/source.lua

@@ -28,21 +28,18 @@ function source.complete(self, _, callback)
 
   for _, snippet in pairs(snippets) do
     local is_regex_snippet = snippet.options:match("r")
-    -- Avoid expanding a regex snippet with an invalid insertText when self.expandable_only == false
-    -- (_cmpu_line_till_cursor is only set when self.expandable_only == true)
-    if not is_regex_snippet or is_regex_snippet and self.expandable_only then
-      local item = {
-        insertText = (is_regex_snippet and snippet.matched) or snippet.trigger,
-        label = snippet.trigger,
-        kind = cmp.lsp.CompletionItemKind.Snippet,
-        snippet = snippet,
-      }
-      table.insert(items, item)
-    end
+    local item = {
+      insertText = (is_regex_snippet and snippet.matched) or snippet.trigger,
+      label = snippet.trigger,
+      kind = cmp.lsp.CompletionItemKind.Snippet,
+      snippet = snippet,
+    }
+    table.insert(items, item)
   end
   callback {
     items = items,
-    -- Cmp will update the items on every keystroke
+    -- If true, cmp will update the items on every keystroke.
+    -- When self.expandable_only == false, the snippets are cached so no need to update.
     isIncomplete = self.expandable_only,
   }
 end