Fixed #1850: trace + debug cannot handle multi line comments

Author: mweststrate

src/core/observable.ts

@@ -273,7 +273,7 @@ You are entering this break point because derivation '${derivation.name}' is bei
 Just follow the stacktrace you should now see in the devtools to see precisely what piece of your code is causing this update
 The stackframe you are looking for is at least ~6-8 stack-frames up.
 
-${derivation instanceof ComputedValue ? derivation.derivation.toString() : ""}
+${derivation instanceof ComputedValue ? derivation.derivation.toString().replace(/[*]\//g, "/") : ""}
 
 The dependencies for this derivation are:
 

test/base/trace.js

@@ -15,6 +15,9 @@ test("trace", () => {
             firstname: "Michel",
             lastname: "Weststrate",
             get fullname() {
+                /* test multi line comment 
+                    (run this unit test from VS code, and pass 'true'  as third argument to trace below to verify) 
+                */
                 var res = this.firstname + " " + this.lastname
                 mobx.trace(this, "fullname")
                 return res
@@ -53,3 +56,25 @@ test("trace", () => {
         console.log = baselog
     }
 })
+
+test("1850", () => {
+    const x = mobx.observable({
+        firstname: "Michel",
+        lastname: "Weststrate",
+        get fullname() {
+            /* test multi line comment 
+                (run this unit test from VS code, to manually verify serialization) 
+            */
+            var res = this.firstname + " " + this.lastname
+            mobx.trace(this, "fullname", true)
+            return res
+        }
+    })
+
+    mobx.autorun(() => {
+        x.fullname
+    })
+    expect(() => {
+        x.firstname += "!"
+    }).not.toThrow("Unexpected identifier")
+})