Merge pull request #381 from jrwats/strip_trailing

Support trailing commas (["a", ], {"a": "b",}) in launch.json files.

Author: nbfalcon

dap-launch.el

@@ -28,8 +28,8 @@
 (require 'f)
 (require 'rx)
 
-(defun dap-launch-remove-comments ()
-  "Remove all C-style comments in the current buffer.
+(defun dap-launch-sanitize-json ()
+  "Remove all C-style comments and trailing commas in the current buffer.
 Comments in strings are ignored. The buffer is modified in place.
 Replacement starts at point, and strings before it are ignored,
 so you may want to move point to `point-min' with `goto-char'
@@ -40,12 +40,13 @@ supported."
            (or (group
                 (or (: "//" (* nonl) eol)
                     (: "/*" (* (or (not (any ?*))
-                                   (: (+ ?*) (not (any ?/))))) (+ ?*) ?/)))
+                                   (: (+ ?*) (not (any ?/))))) (+ ?*) ?/)
+                    (: "," (group (* (any blank ?\C-j)) (any ?\} ?\])))))
                (: "\"" (* (or (not (any ?\\ ?\")) (: ?\\ nonl))) "\"")))
           nil t)
     ;; we matched a comment
     (when (match-beginning 1)
-      (replace-match ""))))
+      (replace-match (or (match-string 2) "")))))
 
 (defun dap-launch-find-launch-json ()
   "Return the location of the launch.json file in the current project."
@@ -66,7 +67,7 @@ supported."
     (with-temp-buffer
       ;; NOTE: insert-file-contents does not move point
       (insert-file-contents launch-json)
-      (dap-launch-remove-comments)
+      (dap-launch-sanitize-json)
       ;; dap-launch-remove-comments does move point
       (goto-char (point-min))
 

test/dap-test.el

@@ -123,13 +123,13 @@
     (should (dap-python--equal actual expected))
     (should (dap-python--equal (dap-python--nearest-test expected) "::TestClass::test_foo"))))
 
-(defun dap-launch-test--delete-string-comments (s)
+(defun dap-launch-test--sanitize-json (s)
   "Delete all comments in S."
   (with-temp-buffer
     (insert s)
     (goto-char (point-min))
 
-    (dap-launch-remove-comments)
+    (dap-launch-sanitize-json)
     (buffer-string)))
 
 (ert-deftest dap-launch-test--delete-comments ()
@@ -139,21 +139,34 @@
 /* \" // non-string */
 \"// string\"
 \"/*string*/\"")
-         (post-exp (dap-launch-test--delete-string-comments orig)))
+         (post-exp (dap-launch-test--sanitize-json orig)))
     (should (string= post-exp "
 
 
 
 \"// string\"
 \"/*string*/\""))))
 
+(ert-deftest dap-launch-test--delete-commas ()
+  (let* ((orig "{
+  \"abc\": 123,
+}")
+        (post-exp (dap-launch-test--sanitize-json orig)))
+    (should (string= post-exp "{
+  \"abc\": 123
+}"))))
+
 (ert-deftest dap-launch-test--comment-in-string ()
   (let ((orig "\"// orig\""))
-    (should (string= orig (dap-launch-test--delete-string-comments orig)))))
+    (should (string= orig (dap-launch-test--sanitize-json orig)))))
 
 (ert-deftest dap-launch-test--comment-star ()
   (let ((orig "/* * **/"))
-    (should (string-empty-p (dap-launch-test--delete-string-comments orig)))))
+    (should (string-empty-p (dap-launch-test--sanitize-json orig)))))
+
+(ert-deftest dap-launch-test--comma-in-string ()
+  (let ((orig "\"abc, ]\""))
+    (should (string= orig (dap-launch-test--sanitize-json orig)))))
 
 
 (defmacro dap-variables--define-compare-test (name conf expanded