CR

Author: OlivierNicole

compiler/lib/source_map.ml

@@ -340,6 +340,9 @@ module Mappings = struct
         0
         edits
     in
+    (* Remove trailing ';' *)
+    if Buffer.length buf > 0 then
+      Buffer.truncate buf (Buffer.length buf - 1);
     Uninterpreted (Buffer.contents buf)
 
   let num_gen_lines m =
@@ -411,6 +414,9 @@ module Mappings = struct
             0
             (List.init ~len:(num_gen_lines m2) ~f:(Fun.const Line_edits.Keep))
         in
+        (* Remove trailing ';' *)
+        if Buffer.length buf > 0 then
+          Buffer.truncate buf (Buffer.length buf - 1);
         Uninterpreted (Buffer.contents buf)
 
   let encode mapping =

compiler/tests-compiler/sourcemap.ml

@@ -153,7 +153,7 @@ let%expect_test _ =
   print_mapping m;
   [%expect
     {|
-    CASU;;GCUU;;;;;;;;;;;;;;;;;;;;GCff;
+    CASU;;GCUU;;;;;;;;;;;;;;;;;;;;GCff
     sa:10:10 -> 1:1
     sb:20:20 -> 3:3
     sa2:5:5 -> 23:3 |}]