experiment with xref

wip starting with inspiration from xref-js2

Author: kermorgant

phpactor.el

@@ -722,6 +722,57 @@ function."
   (let ((arguments (phpactor--command-argments :source :path)))
     (apply #'phpactor-action-dispatch (phpactor--rpc "transform" (append arguments (list :transform "implement_contracts"))))))
 
+(require 'xref)
+
+(defun xref-phpactor-xref-backend ()
+  "Xref-phpactor backend for Xref."
+  'xref-phpactor)
+
+(cl-defmethod xref-backend-definitions ((_backend (eql xref-phpactor)) symbol)
+  (xref-phpactor--xref-find-definitions symbol))
+
+(defun xref-phpactor--xref-find-definitions (symbol)
+  "Return a list of candidates matching SYMBOL."
+  (seq-map (lambda (candidate)
+             (xref-phpactor--make-xref candidate))
+           (xref-phpactor--find-definitions symbol)))
+
+(defun xref-phpactor--make-xref (candidate)
+  "Return a new Xref object built from CANDIDATE."
+  (xref-make (map-elt candidate 'match)
+             (xref-make-file-location (map-elt candidate 'file)
+                                      (map-elt candidate 'line)
+                                      0)))
+
+(defun xref-phpactor--find-definitions (symbol)
+  "Return a list of definitions for SYMBOL from an ag search."
+  (xref-phpactor--find-candidates symbol))
+
+(defun xref-phpactor--find-candidates (symbol)
+  (let ((current-references phpactor-references)
+        matches)
+    (dolist (file-reference current-references)
+      (let ((path (plist-get file-reference :file)))
+        (dolist (reference (plist-get file-reference :references))
+          (when path
+            (push 'matches (list (cons 'file path)
+                                        (cons 'line (plist-get reference :line_no))
+                                        ;; (cons 'symbol symbol)
+                                        ;; (cons 'match match)
+                                        ))))))
+    matches))
+
+(defun xref-phpactor--candidate (symbol file-reference)
+  "Return a candidate alist built from SYMBOL and a raw MATCH result.
+The MATCH is one output result from the ag search."
+  (let* ()
+    ;; Some minified JS files might match a search. To avoid cluttering the
+    ;; search result, we trim the output.
+    (list (cons 'file (expand-file-name (car attrs) (xref-js2--root-dir)))
+          (cons 'line (string-to-number (cadr attrs)))
+          (cons 'symbol symbol)
+          (cons 'match match))))
+
 ;;;###autoload
 (defun phpactor-find-references ()
   "Execute Phpactor RPC references action to find references."