diff --git a/src/harness/fourslashImpl.ts b/src/harness/fourslashImpl.ts
index 4fb6bc885b961..5c7d576a29a4b 100644
--- a/src/harness/fourslashImpl.ts
+++ b/src/harness/fourslashImpl.ts
@@ -4512,16 +4512,42 @@ export class TestState {
     }
 
     public baselineMapCode(
-        { fileName, pos }: Range,
+        ranges: Range[],
         changesFilename: string,
     ): void {
         const changes = this.getFileContent(changesFilename);
-        const beforeContents = this.getFileContent(fileName);
-        const before = beforeContents.slice(0, pos) + "[||]" + beforeContents.slice(pos);
+        let fileName: string | undefined;
+        const focusLocations = ranges.map(({ fileName: fn, pos, end }) => {
+            if (!fileName) {
+                fileName = fn;
+            }
+            return [{ start: pos, length: end - pos }];
+        });
+        if (!fileName) {
+            throw new Error("No ranges passed in, or something went wrong.");
+        }
+        let before = this.getFileContent(fileName);
+        focusLocations.sort((a, b) => a[0].start - b[0].start);
+        for (const subLoc of focusLocations) {
+            for (const { start, length } of subLoc) {
+                let offset = 0;
+                for (const sl2 of focusLocations) {
+                    for (const { start: s2, length: l2 } of sl2) {
+                        if (s2 < start) {
+                            offset += 4;
+                            if ((s2 + l2) > start) {
+                                offset -= 2;
+                            }
+                        }
+                    }
+                }
+                before = before.slice(0, start + offset) + "[|" + before.slice(start + offset, start + offset + length) + "|]" + before.slice(start + offset + length);
+            }
+        }
         const edits = this.languageService.mapCode(
             fileName,
             [changes],
-            [[{ start: pos, length: 1 }]],
+            focusLocations,
             this.formatCodeSettings,
             {},
         );
diff --git a/src/harness/fourslashInterfaceImpl.ts b/src/harness/fourslashInterfaceImpl.ts
index c1262a25ada0f..cc101cc148e58 100644
--- a/src/harness/fourslashInterfaceImpl.ts
+++ b/src/harness/fourslashInterfaceImpl.ts
@@ -240,8 +240,8 @@ export class VerifyNegatable {
         this.state.uncommentSelection(newFileContent);
     }
 
-    public baselineMapCode(range: FourSlash.Range, changesFilename: string): void {
-        this.state.baselineMapCode(range, changesFilename);
+    public baselineMapCode(ranges: FourSlash.Range[], changesFilename: string): void {
+        this.state.baselineMapCode(ranges, changesFilename);
     }
 }
 
diff --git a/tests/baselines/reference/mapCodeReplaceUsingRange.mapCode.ts b/tests/baselines/reference/mapCodeReplaceUsingRange.mapCode.ts
new file mode 100644
index 0000000000000..7afc919ae8aca
--- /dev/null
+++ b/tests/baselines/reference/mapCodeReplaceUsingRange.mapCode.ts
@@ -0,0 +1,22 @@
+// === mapCode ===
+
+// === ORIGINAL ===
+[|function foo() {
+    return 1;
+}[||]
+function bar() {
+    return [|2;|]
+}|]
+
+// === INCOMING CHANGES ===
+function foo() {
+    return 3;
+}
+
+// === MAPPED ===
+function foo() {
+    return 3;
+}
+function bar() {
+    return 2;
+}
diff --git a/tests/cases/fourslash/fourslash.ts b/tests/cases/fourslash/fourslash.ts
index e76d4e4ebb63a..499df9cced4a1 100644
--- a/tests/cases/fourslash/fourslash.ts
+++ b/tests/cases/fourslash/fourslash.ts
@@ -466,7 +466,7 @@ declare namespace FourSlashInterface {
                 copiedFrom?: { file: string, range: { pos: number, end: number }[] };
             }
         }): void;
-        baselineMapCode(range: Range, changesFilename?: string): void;
+        baselineMapCode(ranges: Range[], changesFilename?: string): void;
     }
     class edit {
         caretPosition(): Marker;
diff --git a/tests/cases/fourslash/mapCodeClassInvalidClassMember.ts b/tests/cases/fourslash/mapCodeClassInvalidClassMember.ts
index 6d932edf04b47..0ff05e37b3393 100644
--- a/tests/cases/fourslash/mapCodeClassInvalidClassMember.ts
+++ b/tests/cases/fourslash/mapCodeClassInvalidClassMember.ts
@@ -10,4 +10,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeFocusLocationReplacement.ts b/tests/cases/fourslash/mapCodeFocusLocationReplacement.ts
index 6f7a59c0ff0d7..1c01f6065ab25 100644
--- a/tests/cases/fourslash/mapCodeFocusLocationReplacement.ts
+++ b/tests/cases/fourslash/mapCodeFocusLocationReplacement.ts
@@ -35,4 +35,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeMethodInsertion.ts b/tests/cases/fourslash/mapCodeMethodInsertion.ts
index ce91c8401b85b..3f966f7ef7e6d 100644
--- a/tests/cases/fourslash/mapCodeMethodInsertion.ts
+++ b/tests/cases/fourslash/mapCodeMethodInsertion.ts
@@ -20,4 +20,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeMethodReplacement.ts b/tests/cases/fourslash/mapCodeMethodReplacement.ts
index 1dd1238cb7b11..2787d50af95ff 100644
--- a/tests/cases/fourslash/mapCodeMethodReplacement.ts
+++ b/tests/cases/fourslash/mapCodeMethodReplacement.ts
@@ -20,4 +20,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
diff --git a/tests/cases/fourslash/mapCodeMixedClassDeclaration.ts b/tests/cases/fourslash/mapCodeMixedClassDeclaration.ts
index 1c55f21476be9..1b3d306637c52 100644
--- a/tests/cases/fourslash/mapCodeMixedClassDeclaration.ts
+++ b/tests/cases/fourslash/mapCodeMixedClassDeclaration.ts
@@ -22,4 +22,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedClassIfInsertion.ts b/tests/cases/fourslash/mapCodeNestedClassIfInsertion.ts
index ffb231208984d..8f609e16267d0 100644
--- a/tests/cases/fourslash/mapCodeNestedClassIfInsertion.ts
+++ b/tests/cases/fourslash/mapCodeNestedClassIfInsertion.ts
@@ -22,4 +22,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedClassIfReplacement.ts b/tests/cases/fourslash/mapCodeNestedClassIfReplacement.ts
index 88cdb4c634d76..d944d05fa3f16 100644
--- a/tests/cases/fourslash/mapCodeNestedClassIfReplacement.ts
+++ b/tests/cases/fourslash/mapCodeNestedClassIfReplacement.ts
@@ -22,4 +22,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedForInsertion.ts b/tests/cases/fourslash/mapCodeNestedForInsertion.ts
index efe36833b3bbe..09ead4ee37389 100644
--- a/tests/cases/fourslash/mapCodeNestedForInsertion.ts
+++ b/tests/cases/fourslash/mapCodeNestedForInsertion.ts
@@ -18,4 +18,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedForOfInsertion.ts b/tests/cases/fourslash/mapCodeNestedForOfInsertion.ts
index dce3c6e812d17..4a37e87ec5eab 100644
--- a/tests/cases/fourslash/mapCodeNestedForOfInsertion.ts
+++ b/tests/cases/fourslash/mapCodeNestedForOfInsertion.ts
@@ -16,4 +16,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedForOfReplacement.ts b/tests/cases/fourslash/mapCodeNestedForOfReplacement.ts
index 4b6b352def78d..32c6414c2f01e 100644
--- a/tests/cases/fourslash/mapCodeNestedForOfReplacement.ts
+++ b/tests/cases/fourslash/mapCodeNestedForOfReplacement.ts
@@ -16,4 +16,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedForReplacement.ts b/tests/cases/fourslash/mapCodeNestedForReplacement.ts
index 0bfe1a615bcf2..ced6e5264f425 100644
--- a/tests/cases/fourslash/mapCodeNestedForReplacement.ts
+++ b/tests/cases/fourslash/mapCodeNestedForReplacement.ts
@@ -16,4 +16,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedIfInsertion.ts b/tests/cases/fourslash/mapCodeNestedIfInsertion.ts
index 8c5cdff24e830..1732172c2302e 100644
--- a/tests/cases/fourslash/mapCodeNestedIfInsertion.ts
+++ b/tests/cases/fourslash/mapCodeNestedIfInsertion.ts
@@ -18,4 +18,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedIfReplace.ts b/tests/cases/fourslash/mapCodeNestedIfReplace.ts
index 9f6d1424e5418..c3ca1c5fb8366 100644
--- a/tests/cases/fourslash/mapCodeNestedIfReplace.ts
+++ b/tests/cases/fourslash/mapCodeNestedIfReplace.ts
@@ -18,4 +18,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedLabeledInsertion.ts b/tests/cases/fourslash/mapCodeNestedLabeledInsertion.ts
index ab9266d8b8b7d..fc4a87471da41 100644
--- a/tests/cases/fourslash/mapCodeNestedLabeledInsertion.ts
+++ b/tests/cases/fourslash/mapCodeNestedLabeledInsertion.ts
@@ -20,4 +20,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedLabeledReplace.ts b/tests/cases/fourslash/mapCodeNestedLabeledReplace.ts
index c17ff7e951176..0e60d329af91a 100644
--- a/tests/cases/fourslash/mapCodeNestedLabeledReplace.ts
+++ b/tests/cases/fourslash/mapCodeNestedLabeledReplace.ts
@@ -20,4 +20,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedWhileInsertion.ts b/tests/cases/fourslash/mapCodeNestedWhileInsertion.ts
index 4e8132b4bfb0d..ac98cd69c0f50 100644
--- a/tests/cases/fourslash/mapCodeNestedWhileInsertion.ts
+++ b/tests/cases/fourslash/mapCodeNestedWhileInsertion.ts
@@ -18,4 +18,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeNestedWhileReplace.ts b/tests/cases/fourslash/mapCodeNestedWhileReplace.ts
index eeea214584229..7bd21a9698e18 100644
--- a/tests/cases/fourslash/mapCodeNestedWhileReplace.ts
+++ b/tests/cases/fourslash/mapCodeNestedWhileReplace.ts
@@ -18,4 +18,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeRangeReplacement.ts b/tests/cases/fourslash/mapCodeRangeReplacement.ts
index f94a5ebce6b4a..8fddddb6e918e 100644
--- a/tests/cases/fourslash/mapCodeRangeReplacement.ts
+++ b/tests/cases/fourslash/mapCodeRangeReplacement.ts
@@ -29,4 +29,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeReplaceUsingRange.ts b/tests/cases/fourslash/mapCodeReplaceUsingRange.ts
new file mode 100644
index 0000000000000..fb723acc7c835
--- /dev/null
+++ b/tests/cases/fourslash/mapCodeReplaceUsingRange.ts
@@ -0,0 +1,17 @@
+///<reference path="fourslash.ts"/>
+
+// @Filename: /incomingChanges.ts
+//// function foo() {
+////     return 3;
+//// }
+////
+// @Filename: /index.ts
+//// [|function foo() {
+////     return 1;
+//// }[||]
+//// function bar() {
+////     return [|2;|]
+//// }|]
+////
+
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
diff --git a/tests/cases/fourslash/mapCodeToplevelInsert.ts b/tests/cases/fourslash/mapCodeToplevelInsert.ts
index 6d2c0663b9aca..8b0f7b2c431a8 100644
--- a/tests/cases/fourslash/mapCodeToplevelInsert.ts
+++ b/tests/cases/fourslash/mapCodeToplevelInsert.ts
@@ -13,4 +13,4 @@
 ////     return 2;
 //// }
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file
diff --git a/tests/cases/fourslash/mapCodeToplevelInsertNoClass.ts b/tests/cases/fourslash/mapCodeToplevelInsertNoClass.ts
index 67ec6850c839d..9feb70fb13f04 100644
--- a/tests/cases/fourslash/mapCodeToplevelInsertNoClass.ts
+++ b/tests/cases/fourslash/mapCodeToplevelInsertNoClass.ts
@@ -13,4 +13,4 @@
 ////     return 2;
 //// }
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
diff --git a/tests/cases/fourslash/mapCodeToplevelReplace.ts b/tests/cases/fourslash/mapCodeToplevelReplace.ts
index e605c13ddfc41..dc11d2d702e38 100644
--- a/tests/cases/fourslash/mapCodeToplevelReplace.ts
+++ b/tests/cases/fourslash/mapCodeToplevelReplace.ts
@@ -14,4 +14,4 @@
 //// }
 ////
 
-verify.baselineMapCode(test.ranges()[0], "/incomingChanges.ts");
\ No newline at end of file
+verify.baselineMapCode(test.ranges(), "/incomingChanges.ts");
\ No newline at end of file