prevent company from flickering

Author: wyuenho

lsp-completion.el

@@ -346,36 +346,35 @@ Return `nil' when fails to guess prefix."
 
 (defun lsp-completion--filter-candidates (items)
   "List all possible completions in cached ITEMS with their prefixes."
-  (lsp--while-no-input
-    (--> (let (queries fuz-queries)
-           (-keep (-lambda ((cand &as &plist :label :start-point :score))
-                    (let* ((query (or (plist-get queries start-point)
-                                      (let ((s (buffer-substring-no-properties
-                                                start-point (point))))
-                                        (setq queries (plist-put queries start-point s))
-                                        s)))
-                           (fuz-query (or (plist-get fuz-queries start-point)
-                                          (let ((s (lsp-completion--regex-fuz query)))
-                                            (setq fuz-queries
-                                                  (plist-put fuz-queries start-point s))
-                                            s)))
-                           (label-len (length label))
-                           (case-fold-search completion-ignore-case))
-                      (when (string-match fuz-query label)
-                        (put-text-property 0 label-len 'match-data (match-data) label)
-                        (plist-put cand
-                                   :sort-score
-                                   (* (or (lsp-completion--fuz-score query label) 1e-05)
-                                      (or score 0.001)))
-                        cand)))
-                  items))
-         (if lsp-completion--no-reordering
-             it
-           (sort it (lambda (o1 o2)
-                      (> (plist-get o1 :sort-score)
-                         (plist-get o2 :sort-score)))))
-         ;; TODO: pass additional function to sort the candidates
-         (-map (-rpartial #'plist-get :item) it))))
+  (--> (let (queries fuz-queries)
+         (-keep (-lambda ((cand &as &plist :label :start-point :score))
+                  (let* ((query (or (plist-get queries start-point)
+                                    (let ((s (buffer-substring-no-properties
+                                              start-point (point))))
+                                      (setq queries (plist-put queries start-point s))
+                                      s)))
+                         (fuz-query (or (plist-get fuz-queries start-point)
+                                        (let ((s (lsp-completion--regex-fuz query)))
+                                          (setq fuz-queries
+                                                (plist-put fuz-queries start-point s))
+                                          s)))
+                         (label-len (length label))
+                         (case-fold-search completion-ignore-case))
+                    (when (string-match fuz-query label)
+                      (put-text-property 0 label-len 'match-data (match-data) label)
+                      (plist-put cand
+                                 :sort-score
+                                 (* (or (lsp-completion--fuz-score query label) 1e-05)
+                                    (or score 0.001)))
+                      cand)))
+                items))
+       (if lsp-completion--no-reordering
+           it
+         (sort it (lambda (o1 o2)
+                    (> (plist-get o1 :sort-score)
+                       (plist-get o2 :sort-score)))))
+       ;; TODO: pass additional function to sort the candidates
+       (-map (-rpartial #'plist-get :item) it)))
 
 (defconst lsp-completion--kind->symbol
   '((1 . text)
@@ -580,7 +579,8 @@ Returns resolved completion item details."
                                      (-map
                                       (lambda (item)
                                         (lsp-completion--make-item item :markers markers :prefix prefix))
-                                      (lsp-completion--filter-candidates items)))))
+                                      (lsp--while-no-input
+                                        (lsp-completion--filter-candidates items))))))
                      (t
                       (-let* ((resp (lsp-request-while-no-input
                                      "textDocument/completion"
@@ -621,15 +621,16 @@ Returns resolved completion item details."
                                                            ((not done?) :incomplete))
                                                           :markers markers
                                                           :prefix prefix)
-                              result (when-let ((items
-                                                 (or (and done? (cl-second lsp-completion--cache))
+                              result (-map
+                                      (lambda (item)
+                                        (lsp-completion--make-item item :markers markers :prefix prefix))
+                                      ;; Prevent company from flickering. See #2148.
+                                      (lsp--while-no-input
+                                        (->> (if (or (and done? (cl-second lsp-completion--cache))
                                                      (and lsp-completion-filter-on-incomplete
-                                                          (lsp-completion--to-internal items))
-                                                     items)))
-                                       (-map
-                                        (lambda (item)
-                                          (lsp-completion--make-item item :markers markers :prefix prefix))
-                                        (lsp-completion--filter-candidates items))))))))
+                                                          (lsp-completion--to-internal items)))
+                                                 (lsp-completion--filter-candidates items)
+                                               items)))))))))
                 (:interrupted lsp-completion--last-result)
                 (`,res (setq lsp-completion--last-result res))))))
       (list