diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index d3974da9930..1e495bf538e 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -22233,7 +22233,7 @@ namespace ts {
                 for (const decl of indexSymbol.declarations) {
                     const declaration = <SignatureDeclaration>decl;
                     if (declaration.parameters.length === 1 && declaration.parameters[0].type) {
-                        switch (declaration.parameters[0].type.kind) {
+                        switch (declaration.parameters[0].type!.kind) {
                             case SyntaxKind.StringKeyword:
                                 if (!seenStringIndexer) {
                                     seenStringIndexer = true;
diff --git a/tests/baselines/reference/typesVersions.ambientModules.js b/tests/baselines/reference/typesVersions.ambientModules.js
index 5dc00d8b376..1d7e3f04ec3 100644
--- a/tests/baselines/reference/typesVersions.ambientModules.js
+++ b/tests/baselines/reference/typesVersions.ambientModules.js
@@ -6,7 +6,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
@@ -20,18 +20,18 @@ declare module "ext/other" {
 
 //// [index.d.ts]
 declare module "ext" {
-    export const a = "ts3.0 a";
+    export const a = "ts3.1 a";
 }
 declare module "ext/other" {
-    export const b = "ts3.0 b";
+    export const b = "ts3.1 b";
 }
 
 //// [main.ts]
 import { a } from "ext";
 import { b } from "ext/other";
 
-const aa: "ts3.0 a" = a;
-const bb: "ts3.0 b" = b;
+const aa: "ts3.1 a" = a;
+const bb: "ts3.1 b" = b;
 
 
 //// [main.js]
diff --git a/tests/baselines/reference/typesVersions.ambientModules.symbols b/tests/baselines/reference/typesVersions.ambientModules.symbols
index d8a0ab0f2ca..91d1adacd9c 100644
--- a/tests/baselines/reference/typesVersions.ambientModules.symbols
+++ b/tests/baselines/reference/typesVersions.ambientModules.symbols
@@ -5,25 +5,25 @@ import { a } from "ext";
 import { b } from "ext/other";
 >b : Symbol(b, Decl(main.ts, 1, 8))
 
-const aa: "ts3.0 a" = a;
+const aa: "ts3.1 a" = a;
 >aa : Symbol(aa, Decl(main.ts, 3, 5))
 >a : Symbol(a, Decl(main.ts, 0, 8))
 
-const bb: "ts3.0 b" = b;
+const bb: "ts3.1 b" = b;
 >bb : Symbol(bb, Decl(main.ts, 4, 5))
 >b : Symbol(b, Decl(main.ts, 1, 8))
 
-=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts ===
+=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts ===
 declare module "ext" {
 >"ext" : Symbol("ext", Decl(index.d.ts, 0, 0))
 
-    export const a = "ts3.0 a";
+    export const a = "ts3.1 a";
 >a : Symbol(a, Decl(index.d.ts, 1, 16))
 }
 declare module "ext/other" {
 >"ext/other" : Symbol("ext/other", Decl(index.d.ts, 2, 1))
 
-    export const b = "ts3.0 b";
+    export const b = "ts3.1 b";
 >b : Symbol(b, Decl(index.d.ts, 4, 16))
 }
 
diff --git a/tests/baselines/reference/typesVersions.ambientModules.trace.json b/tests/baselines/reference/typesVersions.ambientModules.trace.json
index f40d37bd7c3..7a442ce5048 100644
--- a/tests/baselines/reference/typesVersions.ambientModules.trace.json
+++ b/tests/baselines/reference/typesVersions.ambientModules.trace.json
@@ -11,27 +11,27 @@
     "File 'tests/cases/conformance/moduleResolution/node_modules/ext.d.ts' does not exist.",
     "'package.json' does not have a 'typings' field.",
     "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/moduleResolution/node_modules/ext/index'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
     "Module name 'index', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/index'.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index' does not exist.",
-    "Loading module as file / folder, candidate module location 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index', target file type 'TypeScript'.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.ts' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.tsx' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts' exist - use it as a name resolution result.",
-    "Resolving real path for 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts', result 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts'.",
-    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts'. ========",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/index'.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index' does not exist.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.ts' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.tsx' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts', result 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts'.",
+    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts'. ========",
     "======== Resolving module 'ext/other' from 'tests/cases/conformance/moduleResolution/main.ts'. ========",
     "Module resolution kind is not specified, using 'NodeJs'.",
     "Loading module 'ext/other' from 'node_modules' folder, target file type 'TypeScript'.",
     "'package.json' has a 'typesVersions' field with version-specific path mappings.",
     "Found 'package.json' at 'tests/cases/conformance/moduleResolution/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
     "Module name 'other', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/other'.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.ts' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.tsx' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.d.ts' does not exist.",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/other'.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.ts' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.d.ts' does not exist.",
     "Directory 'tests/cases/conformance/moduleResolution/node_modules/@types' does not exist, skipping all lookups in it.",
     "Directory 'tests/cases/conformance/node_modules' does not exist, skipping all lookups in it.",
     "Directory 'tests/cases/node_modules' does not exist, skipping all lookups in it.",
@@ -41,11 +41,11 @@
     "Loading module 'ext/other' from 'node_modules' folder, target file type 'JavaScript'.",
     "'package.json' has a 'typesVersions' field with version-specific path mappings.",
     "Found 'package.json' at 'tests/cases/conformance/moduleResolution/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
     "Module name 'other', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/other'.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.js' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.jsx' does not exist.",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/other'.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.js' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.jsx' does not exist.",
     "Directory 'tests/cases/conformance/node_modules' does not exist, skipping all lookups in it.",
     "Directory 'tests/cases/node_modules' does not exist, skipping all lookups in it.",
     "Directory 'tests/node_modules' does not exist, skipping all lookups in it.",
diff --git a/tests/baselines/reference/typesVersions.ambientModules.types b/tests/baselines/reference/typesVersions.ambientModules.types
index 20cd4112ebe..0e81bad67a0 100644
--- a/tests/baselines/reference/typesVersions.ambientModules.types
+++ b/tests/baselines/reference/typesVersions.ambientModules.types
@@ -1,31 +1,31 @@
 === tests/cases/conformance/moduleResolution/main.ts ===
 import { a } from "ext";
->a : "ts3.0 a"
+>a : "ts3.1 a"
 
 import { b } from "ext/other";
->b : "ts3.0 b"
+>b : "ts3.1 b"
 
-const aa: "ts3.0 a" = a;
->aa : "ts3.0 a"
->a : "ts3.0 a"
+const aa: "ts3.1 a" = a;
+>aa : "ts3.1 a"
+>a : "ts3.1 a"
 
-const bb: "ts3.0 b" = b;
->bb : "ts3.0 b"
->b : "ts3.0 b"
+const bb: "ts3.1 b" = b;
+>bb : "ts3.1 b"
+>b : "ts3.1 b"
 
-=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts ===
+=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts ===
 declare module "ext" {
 >"ext" : typeof import("ext")
 
-    export const a = "ts3.0 a";
->a : "ts3.0 a"
->"ts3.0 a" : "ts3.0 a"
+    export const a = "ts3.1 a";
+>a : "ts3.1 a"
+>"ts3.1 a" : "ts3.1 a"
 }
 declare module "ext/other" {
 >"ext/other" : typeof import("ext/other")
 
-    export const b = "ts3.0 b";
->b : "ts3.0 b"
->"ts3.0 b" : "ts3.0 b"
+    export const b = "ts3.1 b";
+>b : "ts3.1 b"
+>"ts3.1 b" : "ts3.1 b"
 }
 
diff --git a/tests/baselines/reference/typesVersions.multiFile.js b/tests/baselines/reference/typesVersions.multiFile.js
index 0d3b91f7b13..14f7fd8aaf4 100644
--- a/tests/baselines/reference/typesVersions.multiFile.js
+++ b/tests/baselines/reference/typesVersions.multiFile.js
@@ -6,7 +6,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
@@ -17,17 +17,17 @@ export const a = "default a";
 export const b = "default b";
 
 //// [index.d.ts]
-export const a = "ts3.0 a";
+export const a = "ts3.1 a";
 
 //// [other.d.ts]
-export const b = "ts3.0 b";
+export const b = "ts3.1 b";
 
 //// [main.ts]
 import { a } from "ext";
 import { b } from "ext/other";
 
-const aa: "ts3.0 a" = a;
-const bb: "ts3.0 b" = b;
+const aa: "ts3.1 a" = a;
+const bb: "ts3.1 b" = b;
 
 
 //// [main.js]
diff --git a/tests/baselines/reference/typesVersions.multiFile.symbols b/tests/baselines/reference/typesVersions.multiFile.symbols
index c79bb054609..11ea8b7857a 100644
--- a/tests/baselines/reference/typesVersions.multiFile.symbols
+++ b/tests/baselines/reference/typesVersions.multiFile.symbols
@@ -6,12 +6,12 @@ export const a = "default a";
 export const b = "default b";
 >b : Symbol(b, Decl(other.d.ts, 0, 12))
 
-=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts ===
-export const a = "ts3.0 a";
+=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts ===
+export const a = "ts3.1 a";
 >a : Symbol(a, Decl(index.d.ts, 0, 12))
 
-=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.d.ts ===
-export const b = "ts3.0 b";
+=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.d.ts ===
+export const b = "ts3.1 b";
 >b : Symbol(b, Decl(other.d.ts, 0, 12))
 
 === tests/cases/conformance/moduleResolution/main.ts ===
@@ -21,11 +21,11 @@ import { a } from "ext";
 import { b } from "ext/other";
 >b : Symbol(b, Decl(main.ts, 1, 8))
 
-const aa: "ts3.0 a" = a;
+const aa: "ts3.1 a" = a;
 >aa : Symbol(aa, Decl(main.ts, 3, 5))
 >a : Symbol(a, Decl(main.ts, 0, 8))
 
-const bb: "ts3.0 b" = b;
+const bb: "ts3.1 b" = b;
 >bb : Symbol(bb, Decl(main.ts, 4, 5))
 >b : Symbol(b, Decl(main.ts, 1, 8))
 
diff --git a/tests/baselines/reference/typesVersions.multiFile.trace.json b/tests/baselines/reference/typesVersions.multiFile.trace.json
index 6884322c301..e7245fa5765 100644
--- a/tests/baselines/reference/typesVersions.multiFile.trace.json
+++ b/tests/baselines/reference/typesVersions.multiFile.trace.json
@@ -11,27 +11,27 @@
     "File 'tests/cases/conformance/moduleResolution/node_modules/ext.d.ts' does not exist.",
     "'package.json' does not have a 'typings' field.",
     "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/moduleResolution/node_modules/ext/index'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
     "Module name 'index', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/index'.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index' does not exist.",
-    "Loading module as file / folder, candidate module location 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index', target file type 'TypeScript'.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.ts' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.tsx' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts' exist - use it as a name resolution result.",
-    "Resolving real path for 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts', result 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts'.",
-    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts'. ========",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/index'.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index' does not exist.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.ts' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.tsx' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts', result 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts'.",
+    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts'. ========",
     "======== Resolving module 'ext/other' from 'tests/cases/conformance/moduleResolution/main.ts'. ========",
     "Module resolution kind is not specified, using 'NodeJs'.",
     "Loading module 'ext/other' from 'node_modules' folder, target file type 'TypeScript'.",
     "'package.json' has a 'typesVersions' field with version-specific path mappings.",
     "Found 'package.json' at 'tests/cases/conformance/moduleResolution/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
     "Module name 'other', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/other'.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.ts' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.tsx' does not exist.",
-    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.d.ts' exist - use it as a name resolution result.",
-    "Resolving real path for 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.d.ts', result 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.d.ts'.",
-    "======== Module name 'ext/other' was successfully resolved to 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.d.ts'. ========"
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/other'.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.ts' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.d.ts', result 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.d.ts'.",
+    "======== Module name 'ext/other' was successfully resolved to 'tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.d.ts'. ========"
 ]
\ No newline at end of file
diff --git a/tests/baselines/reference/typesVersions.multiFile.types b/tests/baselines/reference/typesVersions.multiFile.types
index c0634803d29..734a90067cb 100644
--- a/tests/baselines/reference/typesVersions.multiFile.types
+++ b/tests/baselines/reference/typesVersions.multiFile.types
@@ -8,28 +8,28 @@ export const b = "default b";
 >b : "default b"
 >"default b" : "default b"
 
-=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/index.d.ts ===
-export const a = "ts3.0 a";
->a : "ts3.0 a"
->"ts3.0 a" : "ts3.0 a"
+=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/index.d.ts ===
+export const a = "ts3.1 a";
+>a : "ts3.1 a"
+>"ts3.1 a" : "ts3.1 a"
 
-=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.0/other.d.ts ===
-export const b = "ts3.0 b";
->b : "ts3.0 b"
->"ts3.0 b" : "ts3.0 b"
+=== tests/cases/conformance/moduleResolution/node_modules/ext/ts3.1/other.d.ts ===
+export const b = "ts3.1 b";
+>b : "ts3.1 b"
+>"ts3.1 b" : "ts3.1 b"
 
 === tests/cases/conformance/moduleResolution/main.ts ===
 import { a } from "ext";
->a : "ts3.0 a"
+>a : "ts3.1 a"
 
 import { b } from "ext/other";
->b : "ts3.0 b"
+>b : "ts3.1 b"
 
-const aa: "ts3.0 a" = a;
->aa : "ts3.0 a"
->a : "ts3.0 a"
+const aa: "ts3.1 a" = a;
+>aa : "ts3.1 a"
+>a : "ts3.1 a"
 
-const bb: "ts3.0 b" = b;
->bb : "ts3.0 b"
->b : "ts3.0 b"
+const bb: "ts3.1 b" = b;
+>bb : "ts3.1 b"
+>b : "ts3.1 b"
 
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.js b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.js
index a226df8e873..b1af852940b 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.js
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.js
@@ -6,7 +6,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.symbols b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.symbols
index 15d1718cce7..2e4794ba56a 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.symbols
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.symbols
@@ -13,7 +13,7 @@ export const vb = fb();
 >vb : Symbol(vb, Decl(main.ts, 4, 12))
 >fb : Symbol(fb, Decl(main.ts, 1, 8))
 
-=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts ===
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
 declare module "ext" {
 >"ext" : Symbol("ext", Decl(index.d.ts, 0, 0))
 
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.trace.json b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.trace.json
index f973d37cd58..c3b0e232748 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.trace.json
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.trace.json
@@ -11,27 +11,27 @@
     "File 'tests/cases/conformance/declarationEmit/node_modules/ext.d.ts' does not exist.",
     "'package.json' does not have a 'typings' field.",
     "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
     "Module name 'index', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/index'.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index' does not exist.",
-    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index', target file type 'TypeScript'.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.ts' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.tsx' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts' exist - use it as a name resolution result.",
-    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts'.",
-    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts'. ========",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/index'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index' does not exist.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'.",
+    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'. ========",
     "======== Resolving module 'ext/other' from 'tests/cases/conformance/declarationEmit/main.ts'. ========",
     "Module resolution kind is not specified, using 'NodeJs'.",
     "Loading module 'ext/other' from 'node_modules' folder, target file type 'TypeScript'.",
     "'package.json' has a 'typesVersions' field with version-specific path mappings.",
     "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
     "Module name 'other', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/other'.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.ts' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.tsx' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.d.ts' does not exist.",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/other'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts' does not exist.",
     "Directory 'tests/cases/conformance/declarationEmit/node_modules/@types' does not exist, skipping all lookups in it.",
     "Directory 'tests/cases/conformance/node_modules' does not exist, skipping all lookups in it.",
     "Directory 'tests/cases/node_modules' does not exist, skipping all lookups in it.",
@@ -41,11 +41,11 @@
     "Loading module 'ext/other' from 'node_modules' folder, target file type 'JavaScript'.",
     "'package.json' has a 'typesVersions' field with version-specific path mappings.",
     "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
     "Module name 'other', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/other'.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.js' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.jsx' does not exist.",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/other'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.js' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.jsx' does not exist.",
     "Directory 'tests/cases/conformance/node_modules' does not exist, skipping all lookups in it.",
     "Directory 'tests/cases/node_modules' does not exist, skipping all lookups in it.",
     "Directory 'tests/node_modules' does not exist, skipping all lookups in it.",
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.types b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.types
index 9f47ca9750c..3599ee312a3 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.types
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.ambient.types
@@ -15,7 +15,7 @@ export const vb = fb();
 >fb() : import("ext/other").B
 >fb : () => import("ext/other").B
 
-=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts ===
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
 declare module "ext" {
 >"ext" : typeof import("ext")
 
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.js b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.js
index 4a1edf5c97e..22cdb0087ef 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.js
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.js
@@ -6,7 +6,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.symbols b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.symbols
index e5db0491541..4449de33ded 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.symbols
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.symbols
@@ -14,7 +14,7 @@ export function fb(): B;
 >fb : Symbol(fb, Decl(other.d.ts, 0, 21))
 >B : Symbol(B, Decl(other.d.ts, 0, 0))
 
-=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts ===
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
 export interface A {}
 >A : Symbol(A, Decl(index.d.ts, 0, 0))
 
@@ -22,7 +22,7 @@ export function fa(): A;
 >fa : Symbol(fa, Decl(index.d.ts, 0, 21))
 >A : Symbol(A, Decl(index.d.ts, 0, 0))
 
-=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.d.ts ===
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts ===
 export interface B {}
 >B : Symbol(B, Decl(other.d.ts, 0, 0))
 
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.trace.json b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.trace.json
index 0296a58b896..532e80feac7 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.trace.json
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.trace.json
@@ -11,27 +11,27 @@
     "File 'tests/cases/conformance/declarationEmit/node_modules/ext.d.ts' does not exist.",
     "'package.json' does not have a 'typings' field.",
     "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
     "Module name 'index', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/index'.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index' does not exist.",
-    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index', target file type 'TypeScript'.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.ts' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.tsx' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts' exist - use it as a name resolution result.",
-    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts'.",
-    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts'. ========",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/index'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index' does not exist.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'.",
+    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'. ========",
     "======== Resolving module 'ext/other' from 'tests/cases/conformance/declarationEmit/main.ts'. ========",
     "Module resolution kind is not specified, using 'NodeJs'.",
     "Loading module 'ext/other' from 'node_modules' folder, target file type 'TypeScript'.",
     "'package.json' has a 'typesVersions' field with version-specific path mappings.",
     "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
-    "'package.json' has a 'typesVersions' entry '3.0' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
     "Module name 'other', matched pattern '*'.",
-    "Trying substitution 'ts3.0/*', candidate module location: 'ts3.0/other'.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.ts' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.tsx' does not exist.",
-    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.d.ts' exist - use it as a name resolution result.",
-    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.d.ts'.",
-    "======== Module name 'ext/other' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.d.ts'. ========"
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/other'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts'.",
+    "======== Module name 'ext/other' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts'. ========"
 ]
\ No newline at end of file
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.types b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.types
index 73721bafec1..9f9dd015942 100644
--- a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.types
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFile.types
@@ -8,30 +8,30 @@ export interface B {}
 export function fb(): B;
 >fb : () => B
 
-=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index.d.ts ===
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
 export interface A {}
 export function fa(): A;
 >fa : () => A
 
-=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other.d.ts ===
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts ===
 export interface B {}
 export function fb(): B;
 >fb : () => B
 
 === tests/cases/conformance/declarationEmit/main.ts ===
 import { fa } from "ext";
->fa : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index").A
+>fa : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index").A
 
 import { fb } from "ext/other";
->fb : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other").B
+>fb : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other").B
 
 export const va = fa();
->va : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index").A
->fa() : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index").A
->fa : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/index").A
+>va : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index").A
+>fa() : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index").A
+>fa : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index").A
 
 export const vb = fb();
->vb : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other").B
->fb() : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other").B
->fb : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.0/other").B
+>vb : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other").B
+>fb() : import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other").B
+>fb : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other").B
 
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.errors.txt b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.errors.txt
new file mode 100644
index 00000000000..66624634d9f
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.errors.txt
@@ -0,0 +1,38 @@
+tests/cases/conformance/declarationEmit/main.ts(1,10): error TS2305: Module '"tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index"' has no exported member 'fa'.
+
+
+==== tests/cases/conformance/declarationEmit/tsconfig.json (0 errors) ====
+    {}
+==== tests/cases/conformance/declarationEmit/node_modules/ext/package.json (0 errors) ====
+    {
+        "name": "ext",
+        "version": "1.0.0",
+        "types": "index",
+        "typesVersions": {
+            "3.1": { "*" : ["ts3.1/*"] }
+        }
+    }
+    
+==== tests/cases/conformance/declarationEmit/node_modules/ext/index.d.ts (0 errors) ====
+    export interface A {}
+    export function fa(): A;
+    
+==== tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts (0 errors) ====
+    export interface B {}
+    export function fb(): B;
+    
+==== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts (0 errors) ====
+    export * from "../";
+    
+==== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts (0 errors) ====
+    export * from "../other";
+    
+==== tests/cases/conformance/declarationEmit/main.ts (1 errors) ====
+    import { fa } from "ext";
+             ~~
+!!! error TS2305: Module '"tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index"' has no exported member 'fa'.
+    import { fb } from "ext/other";
+    
+    export const va = fa();
+    export const vb = fb();
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.js b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.js
new file mode 100644
index 00000000000..c7b885d5e9e
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.js
@@ -0,0 +1,46 @@
+//// [tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.ts] ////
+
+//// [package.json]
+{
+    "name": "ext",
+    "version": "1.0.0",
+    "types": "index",
+    "typesVersions": {
+        "3.1": { "*" : ["ts3.1/*"] }
+    }
+}
+
+//// [index.d.ts]
+export interface A {}
+export function fa(): A;
+
+//// [other.d.ts]
+export interface B {}
+export function fb(): B;
+
+//// [index.d.ts]
+export * from "../";
+
+//// [other.d.ts]
+export * from "../other";
+
+//// [main.ts]
+import { fa } from "ext";
+import { fb } from "ext/other";
+
+export const va = fa();
+export const vb = fb();
+
+
+//// [main.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const ext_1 = require("ext");
+const other_1 = require("ext/other");
+exports.va = ext_1.fa();
+exports.vb = other_1.fb();
+
+
+//// [main.d.ts]
+export declare const va: any;
+export declare const vb: import("ext/other").B;
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.symbols b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.symbols
new file mode 100644
index 00000000000..a3367579265
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.symbols
@@ -0,0 +1,37 @@
+=== tests/cases/conformance/declarationEmit/node_modules/ext/index.d.ts ===
+export interface A {}
+>A : Symbol(A, Decl(index.d.ts, 0, 0))
+
+export function fa(): A;
+>fa : Symbol(fa, Decl(index.d.ts, 0, 21))
+>A : Symbol(A, Decl(index.d.ts, 0, 0))
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts ===
+export interface B {}
+>B : Symbol(B, Decl(other.d.ts, 0, 0))
+
+export function fb(): B;
+>fb : Symbol(fb, Decl(other.d.ts, 0, 21))
+>B : Symbol(B, Decl(other.d.ts, 0, 0))
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
+export * from "../";
+No type information for this code.
+No type information for this code.=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts ===
+export * from "../other";
+No type information for this code.
+No type information for this code.=== tests/cases/conformance/declarationEmit/main.ts ===
+import { fa } from "ext";
+>fa : Symbol(fa, Decl(main.ts, 0, 8))
+
+import { fb } from "ext/other";
+>fb : Symbol(fb, Decl(main.ts, 1, 8))
+
+export const va = fa();
+>va : Symbol(va, Decl(main.ts, 3, 12))
+>fa : Symbol(fa, Decl(main.ts, 0, 8))
+
+export const vb = fb();
+>vb : Symbol(vb, Decl(main.ts, 4, 12))
+>fb : Symbol(fb, Decl(main.ts, 1, 8))
+
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.trace.json b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.trace.json
new file mode 100644
index 00000000000..33d5a0e3177
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.trace.json
@@ -0,0 +1,65 @@
+[
+    "======== Resolving module '../' from 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'. ========",
+    "Module resolution kind is not specified, using 'NodeJs'.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/', target file type 'TypeScript'.",
+    "'package.json' does not have a 'typings' field.",
+    "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/ndex/index.d.ts@1.0.0'.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "'package.json' does not have a 'typings' field.",
+    "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
+    "Module name 'index', matched pattern '*'.",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/index'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index' does not exist.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts' exist - use it as a name resolution result.",
+    "======== Module name '../' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'. ========",
+    "======== Resolving module '../other' from 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts'. ========",
+    "Module resolution kind is not specified, using 'NodeJs'.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/other', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts' exist - use it as a name resolution result.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/other.d.ts@1.0.0'.",
+    "======== Module name '../other' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts'. ========",
+    "======== Resolving module 'ext' from 'tests/cases/conformance/declarationEmit/main.ts'. ========",
+    "Module resolution kind is not specified, using 'NodeJs'.",
+    "Loading module 'ext' from 'node_modules' folder, target file type 'TypeScript'.",
+    "'package.json' does not have a 'typings' field.",
+    "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/index.d.ts@1.0.0'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext.d.ts' does not exist.",
+    "'package.json' does not have a 'typings' field.",
+    "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
+    "Module name 'index', matched pattern '*'.",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/index'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index' does not exist.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'.",
+    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'. ========",
+    "======== Resolving module 'ext/other' from 'tests/cases/conformance/declarationEmit/main.ts'. ========",
+    "Module resolution kind is not specified, using 'NodeJs'.",
+    "Loading module 'ext/other' from 'node_modules' folder, target file type 'TypeScript'.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "Module name 'other', matched pattern '*'.",
+    "Trying substitution 'ts3.1/*', candidate module location: 'ts3.1/other'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts'.",
+    "======== Module name 'ext/other' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts'. ========"
+]
\ No newline at end of file
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.types b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.types
new file mode 100644
index 00000000000..05800e1d35d
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.types
@@ -0,0 +1,33 @@
+=== tests/cases/conformance/declarationEmit/node_modules/ext/index.d.ts ===
+export interface A {}
+export function fa(): A;
+>fa : () => A
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts ===
+export interface B {}
+export function fb(): B;
+>fb : () => B
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
+export * from "../";
+No type information for this code.
+No type information for this code.=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/other.d.ts ===
+export * from "../other";
+No type information for this code.
+No type information for this code.=== tests/cases/conformance/declarationEmit/main.ts ===
+import { fa } from "ext";
+>fa : any
+
+import { fb } from "ext/other";
+>fb : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/other").B
+
+export const va = fa();
+>va : any
+>fa() : any
+>fa : any
+
+export const vb = fb();
+>vb : import("tests/cases/conformance/declarationEmit/node_modules/ext/other").B
+>fb() : import("tests/cases/conformance/declarationEmit/node_modules/ext/other").B
+>fb : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/other").B
+
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.js b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.js
new file mode 100644
index 00000000000..86a621161f6
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.js
@@ -0,0 +1,45 @@
+//// [tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.ts] ////
+
+//// [package.json]
+{
+    "name": "ext",
+    "version": "1.0.0",
+    "types": "index",
+    "typesVersions": {
+        "3.1": {
+            "index" : ["ts3.1/index"]
+        }
+    }
+}
+
+//// [index.d.ts]
+export interface A {}
+export function fa(): A;
+
+//// [other.d.ts]
+export interface A2 {}
+export function fa(): A2;
+
+//// [index.d.ts]
+export * from "../other";
+
+//// [main.ts]
+import { fa } from "ext";
+import { fa as fa2 } from "ext/other";
+
+export const va = fa();
+export const va2 = fa2();
+
+
+//// [main.js]
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+const ext_1 = require("ext");
+const other_1 = require("ext/other");
+exports.va = ext_1.fa();
+exports.va2 = other_1.fa();
+
+
+//// [main.d.ts]
+export declare const va: import("ext/other").A2;
+export declare const va2: import("ext/other").A2;
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.symbols b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.symbols
new file mode 100644
index 00000000000..892e521994b
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.symbols
@@ -0,0 +1,35 @@
+=== tests/cases/conformance/declarationEmit/node_modules/ext/index.d.ts ===
+export interface A {}
+>A : Symbol(A, Decl(index.d.ts, 0, 0))
+
+export function fa(): A;
+>fa : Symbol(fa, Decl(index.d.ts, 0, 21))
+>A : Symbol(A, Decl(index.d.ts, 0, 0))
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts ===
+export interface A2 {}
+>A2 : Symbol(A2, Decl(other.d.ts, 0, 0))
+
+export function fa(): A2;
+>fa : Symbol(fa, Decl(other.d.ts, 0, 22))
+>A2 : Symbol(A2, Decl(other.d.ts, 0, 0))
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
+export * from "../other";
+No type information for this code.
+No type information for this code.=== tests/cases/conformance/declarationEmit/main.ts ===
+import { fa } from "ext";
+>fa : Symbol(fa, Decl(main.ts, 0, 8))
+
+import { fa as fa2 } from "ext/other";
+>fa : Symbol(fa2, Decl(main.ts, 1, 8))
+>fa2 : Symbol(fa2, Decl(main.ts, 1, 8))
+
+export const va = fa();
+>va : Symbol(va, Decl(main.ts, 3, 12))
+>fa : Symbol(fa, Decl(main.ts, 0, 8))
+
+export const va2 = fa2();
+>va2 : Symbol(va2, Decl(main.ts, 4, 12))
+>fa2 : Symbol(fa2, Decl(main.ts, 1, 8))
+
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.trace.json b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.trace.json
new file mode 100644
index 00000000000..d31c0730fd9
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.trace.json
@@ -0,0 +1,44 @@
+[
+    "======== Resolving module '../other' from 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'. ========",
+    "Module resolution kind is not specified, using 'NodeJs'.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/other', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts' exist - use it as a name resolution result.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/other.d.ts@1.0.0'.",
+    "======== Module name '../other' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts'. ========",
+    "======== Resolving module 'ext' from 'tests/cases/conformance/declarationEmit/main.ts'. ========",
+    "Module resolution kind is not specified, using 'NodeJs'.",
+    "Loading module 'ext' from 'node_modules' folder, target file type 'TypeScript'.",
+    "'package.json' does not have a 'typings' field.",
+    "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/index.d.ts@1.0.0'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext.d.ts' does not exist.",
+    "'package.json' does not have a 'typings' field.",
+    "'package.json' has 'types' field 'index' that references 'tests/cases/conformance/declarationEmit/node_modules/ext/index'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'index'.",
+    "Module name 'index', matched pattern 'index'.",
+    "Trying substitution 'ts3.1/index', candidate module location: 'ts3.1/index'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index' does not exist.",
+    "Loading module as file / folder, candidate module location 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index', target file type 'TypeScript'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'.",
+    "======== Module name 'ext' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts'. ========",
+    "======== Resolving module 'ext/other' from 'tests/cases/conformance/declarationEmit/main.ts'. ========",
+    "Module resolution kind is not specified, using 'NodeJs'.",
+    "Loading module 'ext/other' from 'node_modules' folder, target file type 'TypeScript'.",
+    "'package.json' has a 'typesVersions' field with version-specific path mappings.",
+    "Found 'package.json' at 'tests/cases/conformance/declarationEmit/node_modules/ext/package.json'. Package ID is 'ext/other/index.d.ts@1.0.0'.",
+    "'package.json' has a 'typesVersions' entry '3.1' that matches compiler version '3.1', looking for a pattern to match module name 'other'.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.ts' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.tsx' does not exist.",
+    "File 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts' exist - use it as a name resolution result.",
+    "Resolving real path for 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts', result 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts'.",
+    "======== Module name 'ext/other' was successfully resolved to 'tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts'. ========"
+]
\ No newline at end of file
diff --git a/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.types b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.types
new file mode 100644
index 00000000000..d2918314133
--- /dev/null
+++ b/tests/baselines/reference/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.types
@@ -0,0 +1,31 @@
+=== tests/cases/conformance/declarationEmit/node_modules/ext/index.d.ts ===
+export interface A {}
+export function fa(): A;
+>fa : () => A
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/other.d.ts ===
+export interface A2 {}
+export function fa(): A2;
+>fa : () => A2
+
+=== tests/cases/conformance/declarationEmit/node_modules/ext/ts3.1/index.d.ts ===
+export * from "../other";
+No type information for this code.
+No type information for this code.=== tests/cases/conformance/declarationEmit/main.ts ===
+import { fa } from "ext";
+>fa : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+
+import { fa as fa2 } from "ext/other";
+>fa : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+>fa2 : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+
+export const va = fa();
+>va : import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+>fa() : import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+>fa : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+
+export const va2 = fa2();
+>va2 : import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+>fa2() : import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+>fa2 : () => import("tests/cases/conformance/declarationEmit/node_modules/ext/other").A2
+
diff --git a/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.ambient.ts b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.ambient.ts
index 27bba8e830e..447f3aaa82a 100644
--- a/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.ambient.ts
+++ b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.ambient.ts
@@ -9,7 +9,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
@@ -22,7 +22,7 @@ declare module "ext/other" {
     export interface B {}
     export function fb(): B;
 }
-// @filename: node_modules/ext/ts3.0/index.d.ts
+// @filename: node_modules/ext/ts3.1/index.d.ts
 declare module "ext" {
     export interface A {}
     export function fa(): A;
diff --git a/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFile.ts b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFile.ts
index dd71b9b13e2..57ae6c1d631 100644
--- a/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFile.ts
+++ b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFile.ts
@@ -8,7 +8,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
@@ -20,11 +20,11 @@ export function fa(): A;
 export interface B {}
 export function fb(): B;
 
-// @filename: node_modules/ext/ts3.0/index.d.ts
+// @filename: node_modules/ext/ts3.1/index.d.ts
 export interface A {}
 export function fa(): A;
 
-// @filename: node_modules/ext/ts3.0/other.d.ts
+// @filename: node_modules/ext/ts3.1/other.d.ts
 export interface B {}
 export function fb(): B;
 
diff --git a/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.ts b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.ts
new file mode 100644
index 00000000000..3391361225d
--- /dev/null
+++ b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToSelf.ts
@@ -0,0 +1,37 @@
+// @traceResolution: true
+// @target: esnext
+// @module: commonjs
+// @declaration: true
+// @filename: node_modules/ext/package.json
+{
+    "name": "ext",
+    "version": "1.0.0",
+    "types": "index",
+    "typesVersions": {
+        "3.1": { "*" : ["ts3.1/*"] }
+    }
+}
+
+// @filename: node_modules/ext/index.d.ts
+export interface A {}
+export function fa(): A;
+
+// @filename: node_modules/ext/other.d.ts
+export interface B {}
+export function fb(): B;
+
+// @filename: node_modules/ext/ts3.1/index.d.ts
+export * from "../";
+
+// @filename: node_modules/ext/ts3.1/other.d.ts
+export * from "../other";
+
+// @filename: main.ts
+import { fa } from "ext";
+import { fb } from "ext/other";
+
+export const va = fa();
+export const vb = fb();
+
+// @filename: tsconfig.json
+{}
\ No newline at end of file
diff --git a/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.ts b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.ts
new file mode 100644
index 00000000000..15072d2a7ed
--- /dev/null
+++ b/tests/cases/conformance/declarationEmit/typesVersionsDeclarationEmit.multiFileBackReferenceToUnmapped.ts
@@ -0,0 +1,36 @@
+// @traceResolution: true
+// @target: esnext
+// @module: commonjs
+// @declaration: true
+// @filename: node_modules/ext/package.json
+{
+    "name": "ext",
+    "version": "1.0.0",
+    "types": "index",
+    "typesVersions": {
+        "3.1": {
+            "index" : ["ts3.1/index"]
+        }
+    }
+}
+
+// @filename: node_modules/ext/index.d.ts
+export interface A {}
+export function fa(): A;
+
+// @filename: node_modules/ext/other.d.ts
+export interface A2 {}
+export function fa(): A2;
+
+// @filename: node_modules/ext/ts3.1/index.d.ts
+export * from "../other";
+
+// @filename: main.ts
+import { fa } from "ext";
+import { fa as fa2 } from "ext/other";
+
+export const va = fa();
+export const va2 = fa2();
+
+// @filename: tsconfig.json
+{}
\ No newline at end of file
diff --git a/tests/cases/conformance/moduleResolution/typesVersions.ambientModules.ts b/tests/cases/conformance/moduleResolution/typesVersions.ambientModules.ts
index ac314e0c313..2de5f470473 100644
--- a/tests/cases/conformance/moduleResolution/typesVersions.ambientModules.ts
+++ b/tests/cases/conformance/moduleResolution/typesVersions.ambientModules.ts
@@ -8,7 +8,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
@@ -20,20 +20,20 @@ declare module "ext/other" {
     export const b = "default b";
 }
 
-// @filename: node_modules/ext/ts3.0/index.d.ts
+// @filename: node_modules/ext/ts3.1/index.d.ts
 declare module "ext" {
-    export const a = "ts3.0 a";
+    export const a = "ts3.1 a";
 }
 declare module "ext/other" {
-    export const b = "ts3.0 b";
+    export const b = "ts3.1 b";
 }
 
 // @filename: main.ts
 import { a } from "ext";
 import { b } from "ext/other";
 
-const aa: "ts3.0 a" = a;
-const bb: "ts3.0 b" = b;
+const aa: "ts3.1 a" = a;
+const bb: "ts3.1 b" = b;
 
 // @filename: tsconfig.json
 {}
\ No newline at end of file
diff --git a/tests/cases/conformance/moduleResolution/typesVersions.multiFile.ts b/tests/cases/conformance/moduleResolution/typesVersions.multiFile.ts
index c9001ca2219..8d57630af21 100644
--- a/tests/cases/conformance/moduleResolution/typesVersions.multiFile.ts
+++ b/tests/cases/conformance/moduleResolution/typesVersions.multiFile.ts
@@ -7,7 +7,7 @@
     "version": "1.0.0",
     "types": "index",
     "typesVersions": {
-        "3.0": { "*" : ["ts3.0/*"] }
+        "3.1": { "*" : ["ts3.1/*"] }
     }
 }
 
@@ -17,18 +17,18 @@ export const a = "default a";
 // @filename: node_modules/ext/other.d.ts
 export const b = "default b";
 
-// @filename: node_modules/ext/ts3.0/index.d.ts
-export const a = "ts3.0 a";
+// @filename: node_modules/ext/ts3.1/index.d.ts
+export const a = "ts3.1 a";
 
-// @filename: node_modules/ext/ts3.0/other.d.ts
-export const b = "ts3.0 b";
+// @filename: node_modules/ext/ts3.1/other.d.ts
+export const b = "ts3.1 b";
 
 // @filename: main.ts
 import { a } from "ext";
 import { b } from "ext/other";
 
-const aa: "ts3.0 a" = a;
-const bb: "ts3.0 b" = b;
+const aa: "ts3.1 a" = a;
+const bb: "ts3.1 b" = b;
 
 // @filename: tsconfig.json
 {}
\ No newline at end of file