diff --git a/packages/babel-core/test/fixtures/parse/output.json b/packages/babel-core/test/fixtures/parse/output.json
index 5c48f0e09836..1a400f953757 100644
--- a/packages/babel-core/test/fixtures/parse/output.json
+++ b/packages/babel-core/test/fixtures/parse/output.json
@@ -6,11 +6,13 @@
   "loc": {
     "start": {
       "line": 1,
-      "column": 0
+      "column": 0,
+      "index": 0
     },
     "end": {
       "line": 7,
-      "column": 0
+      "column": 0,
+      "index": 91
     }
   },
   "program": {
@@ -20,11 +22,13 @@
     "loc": {
       "start": {
         "line": 1,
-        "column": 0
+        "column": 0,
+        "index": 0
       },
       "end": {
         "line": 7,
-        "column": 0
+        "column": 0,
+        "index": 91
       }
     },
     "interpreter": null,
@@ -37,11 +41,13 @@
         "loc": {
           "start": {
             "line": 1,
-            "column": 0
+            "column": 0,
+            "index": 0
           },
           "end": {
             "line": 2,
-            "column": 17
+            "column": 17,
+            "index": 29
           }
         },
         "decorators": [
@@ -52,11 +58,13 @@
             "loc": {
               "start": {
                 "line": 1,
-                "column": 0
+                "column": 0,
+                "index": 0
               },
               "end": {
                 "line": 1,
-                "column": 11
+                "column": 11,
+                "index": 11
               }
             },
             "expression": {
@@ -66,11 +74,13 @@
               "loc": {
                 "start": {
                   "line": 1,
-                  "column": 1
+                  "column": 1,
+                  "index": 1
                 },
                 "end": {
                   "line": 1,
-                  "column": 11
+                  "column": 11,
+                  "index": 11
                 },
                 "identifierName": "annotation"
               },
@@ -85,11 +95,13 @@
           "loc": {
             "start": {
               "line": 2,
-              "column": 6
+              "column": 6,
+              "index": 18
             },
             "end": {
               "line": 2,
-              "column": 13
+              "column": 13,
+              "index": 25
             },
             "identifierName": "MyClass"
           },
@@ -103,11 +115,13 @@
           "loc": {
             "start": {
               "line": 2,
-              "column": 14
+              "column": 14,
+              "index": 26
             },
             "end": {
               "line": 2,
-              "column": 17
+              "column": 17,
+              "index": 29
             }
           },
           "body": []
@@ -120,11 +134,13 @@
         "loc": {
           "start": {
             "line": 4,
-            "column": 0
+            "column": 0,
+            "index": 31
           },
           "end": {
             "line": 6,
-            "column": 1
+            "column": 1,
+            "index": 90
           }
         },
         "id": {
@@ -134,11 +150,13 @@
           "loc": {
             "start": {
               "line": 4,
-              "column": 9
+              "column": 9,
+              "index": 40
             },
             "end": {
               "line": 4,
-              "column": 19
+              "column": 19,
+              "index": 50
             },
             "identifierName": "annotation"
           },
@@ -154,11 +172,13 @@
             "loc": {
               "start": {
                 "line": 4,
-                "column": 20
+                "column": 20,
+                "index": 51
               },
               "end": {
                 "line": 4,
-                "column": 26
+                "column": 26,
+                "index": 57
               },
               "identifierName": "target"
             },
@@ -172,11 +192,13 @@
           "loc": {
             "start": {
               "line": 4,
-              "column": 28
+              "column": 28,
+              "index": 59
             },
             "end": {
               "line": 6,
-              "column": 1
+              "column": 1,
+              "index": 90
             }
           },
           "body": [
@@ -187,11 +209,13 @@
               "loc": {
                 "start": {
                   "line": 5,
-                  "column": 3
+                  "column": 3,
+                  "index": 64
                 },
                 "end": {
                   "line": 5,
-                  "column": 27
+                  "column": 27,
+                  "index": 88
                 }
               },
               "expression": {
@@ -201,11 +225,13 @@
                 "loc": {
                   "start": {
                     "line": 5,
-                    "column": 3
+                    "column": 3,
+                    "index": 64
                   },
                   "end": {
                     "line": 5,
-                    "column": 26
+                    "column": 26,
+                    "index": 87
                   }
                 },
                 "operator": "=",
@@ -216,11 +242,13 @@
                   "loc": {
                     "start": {
                       "line": 5,
-                      "column": 3
+                      "column": 3,
+                      "index": 64
                     },
                     "end": {
                       "line": 5,
-                      "column": 19
+                      "column": 19,
+                      "index": 80
                     }
                   },
                   "object": {
@@ -230,11 +258,13 @@
                     "loc": {
                       "start": {
                         "line": 5,
-                        "column": 3
+                        "column": 3,
+                        "index": 64
                       },
                       "end": {
                         "line": 5,
-                        "column": 9
+                        "column": 9,
+                        "index": 70
                       },
                       "identifierName": "target"
                     },
@@ -247,11 +277,13 @@
                     "loc": {
                       "start": {
                         "line": 5,
-                        "column": 10
+                        "column": 10,
+                        "index": 71
                       },
                       "end": {
                         "line": 5,
-                        "column": 19
+                        "column": 19,
+                        "index": 80
                       },
                       "identifierName": "annotated"
                     },
@@ -266,11 +298,13 @@
                   "loc": {
                     "start": {
                       "line": 5,
-                      "column": 22
+                      "column": 22,
+                      "index": 83
                     },
                     "end": {
                       "line": 5,
-                      "column": 26
+                      "column": 26,
+                      "index": 87
                     }
                   },
                   "value": true
diff --git a/packages/babel-traverse/test/scope.js b/packages/babel-traverse/test/scope.js
index 604325adcb54..ea3375d18e0d 100644
--- a/packages/babel-traverse/test/scope.js
+++ b/packages/babel-traverse/test/scope.js
@@ -442,10 +442,12 @@ describe("scope", () => {
         expect(referencePaths[0].node.loc.start).toEqual({
           line: 1,
           column: 28,
+          index: 28,
         });
         expect(referencePaths[1].node.loc.start).toEqual({
           line: 1,
           column: 32,
+          index: 32,
         });
       });
       it("id referenced in function body", () => {