Develop a multi threaded asynchronous completion backend

Develop a multi-threaded asynchronous completion backend

lsp-bridge builds the completion backend based on Python's multi-threading technology. With the support of multi-threading technology, no matter how much data you search, lsp-bridge will ensure that the completion experience smooth as butter. Please refer to the design of the existing backend (lsp-bridge/acm/acm-backend-*.el) for complicated backend.

For some small scenarios, such as a language that needs to add additional keyword completion, lsp-bridge provides some scaffolding code to help you quickly build your own asynchronous completion backend:

1. Cache keyword list

(lsp-bridge-call-async "search_list_update" "example" (list "keyword_a" "keyword_b" "keyword_c") 100 "lsp-bridge-example-record")

We can quickly cache the keyword list to the Python process of lsp-bridge through the interface function search_list_update, where example is the name of the completion backend, (list "keyword_a" "keyword_b" "keyword_c") is the keyword list, 100 is the maximum number of search candidates, lsp-bridge-example-record is the name of the callback function called after the search is completed.

2. Multi-threaded search and filter

(lsp-bridge-call-async "search_list_search" "example" "current_symbol")

After completing the keyword cache, search through the interface function search_list_search, where example is the name of the completion backend, and current_symbol is the search keyword, which is generally the symbol at the cursor. When calling search_list_search, lsp-bridge will automatically use sub-threads to search and filter, and automatically detect whether the search results have expired? If the search result is not expired, call the callback function lsp-bridge-example-record to record the search result.

3. Asynchronous data pop-up completion

(defun lsp-bridge-example-record (candidates)
   (setq-local acm-backend-example-items candidates)
   (lsp-bridge-try-completion))

Generally, lsp-bridge-example-record is defined in this way. After receiving candidates returned by the asynchronous backend, first save the search results in the buffer, here is acm-backend-example-items local variable (you need to define this variable yourself), and then call the function lsp-bridge-try-completion, try to popup the completion menu.