Merge #2875

2875: Improve parameter hints a bit & add emacs support r=matklad a=flodiebold

 - just include the name, not e.g. `mut`
 - don't return empty hints (or `_`)

CC @brotzeit for the Emacs change

Co-authored-by: Florian Diebold <[email protected]>

1 files changed, 13 insertions, 6 deletions

diff --git a/editors/emacs/rust-analyzer.el b/editors/emacs/rust-analyzer.el
index 8ba98bf61..06db4f15f 100644
--- a/editors/emacs/rust-analyzer.el
+++ b/editors/emacs/rust-analyzer.el
@@ -210,9 +210,9 @@
 ;; inlay hints
 (defun rust-analyzer--update-inlay-hints (buffer)
   (if (and (rust-analyzer--initialized?) (eq buffer (current-buffer)))
-    (lsp-send-request-async
-     (lsp-make-request "rust-analyzer/inlayHints"
-                       (list :textDocument (lsp--text-document-identifier)))
+    (lsp-request-async
+     "rust-analyzer/inlayHints"
+     (list :textDocument (lsp--text-document-identifier))
      (lambda (res)
        (remove-overlays (point-min) (point-max) 'rust-analyzer--inlay-hint t)
        (dolist (hint res)
@@ -221,9 +221,16 @@
                  (overlay (make-overlay beg end)))
            (overlay-put overlay 'rust-analyzer--inlay-hint t)
            (overlay-put overlay 'evaporate t)
-           (overlay-put overlay 'after-string (propertize (concat ": " label)
-                                                          'font-lock-face 'font-lock-comment-face)))))
-     'tick))
+           (cond
+            ((string= kind "TypeHint")
+             (overlay-put overlay 'after-string (propertize (concat ": " label)
+                                                            'font-lock-face 'font-lock-comment-face)))
+            ((string= kind "ParameterHint")
+             (overlay-put overlay 'before-string (propertize (concat label ": ")
+                                                            'font-lock-face 'font-lock-comment-face)))
+            )
+           )))
+     :mode 'tick))
   nil)
 
 (defvar-local rust-analyzer--inlay-hints-timer nil)