add simple CodeAction that can fix intensional unused variable

Signed-off-by: Lîm Tsú-thuàn <[email protected]>

Author: dannypsnl

doc-trace.rkt

@@ -22,6 +22,7 @@
     (define completions (list))
     (define requires (make-interval-map))
     (define definitions (make-hash))
+    (define quickfixs (mutable-set))
     ;; decl -> (set pos ...)
     (define sym-decls (make-interval-map))
     ;; pos -> decl
@@ -33,7 +34,8 @@
       (set! sym-decls (make-interval-map))
       (set! sym-bindings (make-interval-map))
       (set! requires (make-interval-map))
-      (set! definitions (make-hash)))
+      (set! definitions (make-hash))
+      (set! quickfixs (mutable-set)))
     (define/public (expand start end)
       (define inc (- end start))
       (move-interior-intervals sym-decls (- start 1) inc)
@@ -72,6 +74,7 @@
     (define/public (get-sym-decls) sym-decls)
     (define/public (get-sym-bindings) sym-bindings)
     (define/public (get-definitions) definitions)
+    (define/public (get-quickfixs) quickfixs)
     ;; Overrides
     (define/override (syncheck:find-source-object stx)
       (and (equal? src (syntax-source stx))
@@ -90,6 +93,22 @@
                                  #:severity Diag-Information
                                  #:source (path->uri src-obj)
                                  #:message "unused variable"))
+
+        (set-add! quickfixs
+                  (CodeAction
+                   #:title "Add prefix `_` to ignore"
+                   #:kind "quickfix"
+                   #:diagnostics (list diag)
+                   #:isPreferred #f
+                   #:edit (WorkspaceEdit
+                           #:changes
+                           (hasheq (string->symbol (path->uri src-obj))
+                                   (TextEdit #:range (Range #:start (abs-pos->Pos doc-text start)
+                                                            #:end   (abs-pos->Pos doc-text finish))
+                                             #:newText "_")))
+                   #:data (Range #:start (abs-pos->Pos doc-text start)
+                                 #:end   (abs-pos->Pos doc-text finish))))
+
         (set-add! warn-diags diag)))
     (define/override (syncheck:add-mouse-over-status src-obj start finish text)
       ;; Infer a length of 1 for zero-length ranges in the document.

interfaces.rkt

@@ -11,6 +11,14 @@
 (define-json-expander TextEdit
   [range any/c]
   [newText string?])
+(define-json-expander CodeAction
+  [title string?]
+  [kind string?]
+  [diagnostics any/c]
+  [isPreferred boolean?]
+  [edit any/c]
+  ;; here, we put edit range
+  [data any/c])
 
 (define-json-expander Diagnostic
   [range any/c]

methods.rkt

@@ -61,6 +61,8 @@
        (shutdown id)]
       ["textDocument/hover"
        (text-document/hover id params)]
+      ["textDocument/codeAction"
+       (text-document/code-action id params)]
       ["textDocument/completion"
        (text-document/completion id params)]
       ["textDocument/signatureHelp"
@@ -127,6 +129,7 @@
      (define server-capabilities
        (hasheq 'textDocumentSync sync-options
                'hoverProvider #t
+               'codeActionProvider #t
                'definitionProvider #t
                'referencesProvider #t
                'completionProvider (hasheq 'triggerCharacters (list "("))
@@ -155,3 +158,4 @@
  (contract-out
   [process-message
    (jsexpr? . -> . void?)]))
+

text-document.rkt

@@ -149,6 +149,25 @@
     [_
      (error-response id INVALID-PARAMS "textDocument/hover failed")]))
 
+;; Code Action request
+(define (code-action id params)
+  (match params
+    [(hash-table ['textDocument (DocIdentifier #:uri uri)]
+                 ['range range]
+                 ; TODO: _ctx has three fields
+                 ; 1. `diagnostics`
+                 ; 2. `only: CodeActionKind[]` server should use this to filter out client-unwanted code action
+                 ; 3. `triggerKind?: CodeActionTriggerKind` the reason why code action were requested
+                 ['context _ctx])
+     #:when (uri-is-path? uri)
+     (match-define (doc _doc-text doc-trace)
+       (hash-ref open-docs (string->symbol uri)))
+     (define code-action-list (set->list (send doc-trace get-quickfixs)))
+     (success-response id code-action-list)]
+    [(hash-table ['textDocument (DocIdentifier #:uri uri)])
+     (error-response id INVALID-PARAMS (format "textDocument/codeAction failed uri is not a path ~a" uri))]
+    [_ (error-response id INVALID-PARAMS "textDocument/codeAction failed")]))
+
 ;; Signature Help request
 (define (signatureHelp id params)
   (match params
@@ -584,6 +603,7 @@
   [did-close! (jsexpr? . -> . void?)]
   [did-change! (jsexpr? . -> . void?)]
   [hover (exact-nonnegative-integer? jsexpr? . -> . jsexpr?)]
+  [code-action (exact-positive-integer? jsexpr? . -> . jsexpr?)]
   [completion (exact-nonnegative-integer? jsexpr? . -> . jsexpr?)]
   [signatureHelp (exact-nonnegative-integer? jsexpr? . -> . jsexpr?)]
   [definition (exact-nonnegative-integer? jsexpr? . -> . jsexpr?)]