diff --git a/tests/baselines/reference/nonIdenticalTypeConstraints.errors.txt b/tests/baselines/reference/nonIdenticalTypeConstraints.errors.txt
new file mode 100644
index 00000000000..a8b54bf44dd
--- /dev/null
+++ b/tests/baselines/reference/nonIdenticalTypeConstraints.errors.txt
@@ -0,0 +1,50 @@
+tests/cases/compiler/nonIdenticalTypeConstraints.ts(10,11): error TS2428: All declarations must have identical type parameters.
+tests/cases/compiler/nonIdenticalTypeConstraints.ts(16,7): error TS2428: All declarations must have identical type parameters.
+tests/cases/compiler/nonIdenticalTypeConstraints.ts(36,11): error TS2428: All declarations must have identical type parameters.
+
+
+==== tests/cases/compiler/nonIdenticalTypeConstraints.ts (3 errors) ====
+    class Different {
+        a: number;
+        b: string;
+        c: boolean;
+    }
+    
+    class Foo<T extends Function> {
+        n: T;
+    }
+    interface Foo<T extends Different> {
+              ~~~
+!!! error TS2428: All declarations must have identical type parameters.
+        y: T;
+    }
+    interface Qux<T extends Different> {
+        y: T;
+    }
+    class Qux<T extends Function> {
+          ~~~
+!!! error TS2428: All declarations must have identical type parameters.
+        n: T;
+    }
+    
+    class Bar<T extends Function> {
+        n: T;
+    }
+    interface Bar<T extends Function> {
+        y: T;
+    }
+    interface Baz<T extends Function> {
+        y: T;
+    }
+    class Baz<T extends Function> {
+        n: T;
+    }
+    
+    class Quux<T> {
+        n: T;
+    }
+    interface Quux<U> {
+              ~~~~
+!!! error TS2428: All declarations must have identical type parameters.
+        m: U;
+    }
\ No newline at end of file
diff --git a/tests/baselines/reference/nonIdenticalTypeConstraints.js b/tests/baselines/reference/nonIdenticalTypeConstraints.js
new file mode 100644
index 00000000000..73748f63885
--- /dev/null
+++ b/tests/baselines/reference/nonIdenticalTypeConstraints.js
@@ -0,0 +1,71 @@
+//// [nonIdenticalTypeConstraints.ts]
+class Different {
+    a: number;
+    b: string;
+    c: boolean;
+}
+
+class Foo<T extends Function> {
+    n: T;
+}
+interface Foo<T extends Different> {
+    y: T;
+}
+interface Qux<T extends Different> {
+    y: T;
+}
+class Qux<T extends Function> {
+    n: T;
+}
+
+class Bar<T extends Function> {
+    n: T;
+}
+interface Bar<T extends Function> {
+    y: T;
+}
+interface Baz<T extends Function> {
+    y: T;
+}
+class Baz<T extends Function> {
+    n: T;
+}
+
+class Quux<T> {
+    n: T;
+}
+interface Quux<U> {
+    m: U;
+}
+
+//// [nonIdenticalTypeConstraints.js]
+var Different = (function () {
+    function Different() {
+    }
+    return Different;
+}());
+var Foo = (function () {
+    function Foo() {
+    }
+    return Foo;
+}());
+var Qux = (function () {
+    function Qux() {
+    }
+    return Qux;
+}());
+var Bar = (function () {
+    function Bar() {
+    }
+    return Bar;
+}());
+var Baz = (function () {
+    function Baz() {
+    }
+    return Baz;
+}());
+var Quux = (function () {
+    function Quux() {
+    }
+    return Quux;
+}());
diff --git a/tests/cases/compiler/nonIdenticalTypeConstraints.ts b/tests/cases/compiler/nonIdenticalTypeConstraints.ts
new file mode 100644
index 00000000000..c0271edc91a
--- /dev/null
+++ b/tests/cases/compiler/nonIdenticalTypeConstraints.ts
@@ -0,0 +1,38 @@
+class Different {
+    a: number;
+    b: string;
+    c: boolean;
+}
+
+class Foo<T extends Function> {
+    n: T;
+}
+interface Foo<T extends Different> {
+    y: T;
+}
+interface Qux<T extends Different> {
+    y: T;
+}
+class Qux<T extends Function> {
+    n: T;
+}
+
+class Bar<T extends Function> {
+    n: T;
+}
+interface Bar<T extends Function> {
+    y: T;
+}
+interface Baz<T extends Function> {
+    y: T;
+}
+class Baz<T extends Function> {
+    n: T;
+}
+
+class Quux<T> {
+    n: T;
+}
+interface Quux<U> {
+    m: U;
+}
\ No newline at end of file