diff --git a/tests/baselines/reference/distributiveConditionalTypeConstraints.errors.txt b/tests/baselines/reference/distributiveConditionalTypeConstraints.errors.txt
new file mode 100644
index 0000000000000..2b455f4e2eebd
--- /dev/null
+++ b/tests/baselines/reference/distributiveConditionalTypeConstraints.errors.txt
@@ -0,0 +1,108 @@
+distributiveConditionalTypeConstraints.ts(4,9): error TS2322: Type 'boolean' is not assignable to type 'true'.
+distributiveConditionalTypeConstraints.ts(5,9): error TS2322: Type 'boolean' is not assignable to type 'false'.
+distributiveConditionalTypeConstraints.ts(10,9): error TS2322: Type 'IsArray<T>' is not assignable to type 'false'.
+  Type 'true' is not assignable to type 'false'.
+distributiveConditionalTypeConstraints.ts(15,9): error TS2322: Type 'IsArray<T>' is not assignable to type 'false'.
+  Type 'true' is not assignable to type 'false'.
+distributiveConditionalTypeConstraints.ts(19,9): error TS2322: Type 'IsArray<T>' is not assignable to type 'true'.
+  Type 'false' is not assignable to type 'true'.
+
+
+==== distributiveConditionalTypeConstraints.ts (5 errors) ====
+    type IsArray<T> = T extends unknown[] ? true : false;
+    
+    function f1<T extends object>(x: IsArray<T>) {
+        let t: true = x;   // Error
+            ~
+!!! error TS2322: Type 'boolean' is not assignable to type 'true'.
+        let f: false = x;  // Error
+            ~
+!!! error TS2322: Type 'boolean' is not assignable to type 'false'.
+    }
+    
+    function f2<T extends unknown[]>(x: IsArray<T>) {
+        let t: true = x;
+        let f: false = x;  // Error
+            ~
+!!! error TS2322: Type 'IsArray<T>' is not assignable to type 'false'.
+!!! error TS2322:   Type 'true' is not assignable to type 'false'.
+    }
+    
+    function f3<T extends string[]>(x: IsArray<T>) {
+        let t: true = x;
+        let f: false = x;  // Error
+            ~
+!!! error TS2322: Type 'IsArray<T>' is not assignable to type 'false'.
+!!! error TS2322:   Type 'true' is not assignable to type 'false'.
+    }
+    
+    function f4<T extends Function>(x: IsArray<T>) {
+        let t: true = x;   // Error
+            ~
+!!! error TS2322: Type 'IsArray<T>' is not assignable to type 'true'.
+!!! error TS2322:   Type 'false' is not assignable to type 'true'.
+        let f: false = x;
+    }
+    
+    type ZeroOf<T> =
+        T extends null ? null :
+        T extends undefined ? undefined :
+        T extends string ? "" :
+        T extends number ? 0 :
+        T extends boolean ? false :
+        never;
+    
+    function f10<T extends {}>(x: ZeroOf<T>) {
+        let t: "" | 0 | false = x;
+    }
+    
+    // Modified repro from #30152
+    
+    interface A { foo(): void; }
+    interface B { bar(): void; }
+    interface C { foo(): void, bar(): void }
+    
+    function test1<T extends A>(y: T extends B ? number : string) {
+        if (typeof y == 'string') {
+            y;  // T extends B ? number : string
+        }
+        else {
+            y;  // never
+        }
+        const newY: string | number = y;
+        newY;  // string
+    }
+    
+    function test2<T extends A>(y: T extends B ? string : number) {
+        if (typeof y == 'string') {
+            y;  // never
+        }
+        else {
+            y;  // T extends B ? string : number
+        }
+        const newY: string | number = y;
+        newY;  // number 
+    }
+    
+    function test3<T extends A>(y: T extends C ? number : string) {
+        if (typeof y == 'string') {
+            y;  // (T extends C ? number : string) & string
+        }
+        else {
+            y;  // T extends C ? number : string
+        }
+        const newY: string | number = y;
+        newY;  // string | number
+    }
+    
+    function test4<T extends A>(y: T extends C ? string : number) {
+        if (typeof y == 'string') {
+            y;  // (T extends C ? string : number) & string
+        }
+        else {
+            y;  // T extends C ? string : number
+        }
+        const newY: string | number = y;
+        newY;  // string | number
+    }
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/distributiveConditionalTypeConstraints.symbols b/tests/baselines/reference/distributiveConditionalTypeConstraints.symbols
new file mode 100644
index 0000000000000..762237abde362
--- /dev/null
+++ b/tests/baselines/reference/distributiveConditionalTypeConstraints.symbols
@@ -0,0 +1,225 @@
+//// [tests/cases/compiler/distributiveConditionalTypeConstraints.ts] ////
+
+=== distributiveConditionalTypeConstraints.ts ===
+type IsArray<T> = T extends unknown[] ? true : false;
+>IsArray : Symbol(IsArray, Decl(distributiveConditionalTypeConstraints.ts, 0, 0))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 0, 13))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 0, 13))
+
+function f1<T extends object>(x: IsArray<T>) {
+>f1 : Symbol(f1, Decl(distributiveConditionalTypeConstraints.ts, 0, 53))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 2, 12))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 2, 30))
+>IsArray : Symbol(IsArray, Decl(distributiveConditionalTypeConstraints.ts, 0, 0))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 2, 12))
+
+    let t: true = x;   // Error
+>t : Symbol(t, Decl(distributiveConditionalTypeConstraints.ts, 3, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 2, 30))
+
+    let f: false = x;  // Error
+>f : Symbol(f, Decl(distributiveConditionalTypeConstraints.ts, 4, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 2, 30))
+}
+
+function f2<T extends unknown[]>(x: IsArray<T>) {
+>f2 : Symbol(f2, Decl(distributiveConditionalTypeConstraints.ts, 5, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 7, 12))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 7, 33))
+>IsArray : Symbol(IsArray, Decl(distributiveConditionalTypeConstraints.ts, 0, 0))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 7, 12))
+
+    let t: true = x;
+>t : Symbol(t, Decl(distributiveConditionalTypeConstraints.ts, 8, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 7, 33))
+
+    let f: false = x;  // Error
+>f : Symbol(f, Decl(distributiveConditionalTypeConstraints.ts, 9, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 7, 33))
+}
+
+function f3<T extends string[]>(x: IsArray<T>) {
+>f3 : Symbol(f3, Decl(distributiveConditionalTypeConstraints.ts, 10, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 12, 12))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 12, 32))
+>IsArray : Symbol(IsArray, Decl(distributiveConditionalTypeConstraints.ts, 0, 0))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 12, 12))
+
+    let t: true = x;
+>t : Symbol(t, Decl(distributiveConditionalTypeConstraints.ts, 13, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 12, 32))
+
+    let f: false = x;  // Error
+>f : Symbol(f, Decl(distributiveConditionalTypeConstraints.ts, 14, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 12, 32))
+}
+
+function f4<T extends Function>(x: IsArray<T>) {
+>f4 : Symbol(f4, Decl(distributiveConditionalTypeConstraints.ts, 15, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 17, 12))
+>Function : Symbol(Function, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 17, 32))
+>IsArray : Symbol(IsArray, Decl(distributiveConditionalTypeConstraints.ts, 0, 0))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 17, 12))
+
+    let t: true = x;   // Error
+>t : Symbol(t, Decl(distributiveConditionalTypeConstraints.ts, 18, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 17, 32))
+
+    let f: false = x;
+>f : Symbol(f, Decl(distributiveConditionalTypeConstraints.ts, 19, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 17, 32))
+}
+
+type ZeroOf<T> =
+>ZeroOf : Symbol(ZeroOf, Decl(distributiveConditionalTypeConstraints.ts, 20, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 22, 12))
+
+    T extends null ? null :
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 22, 12))
+
+    T extends undefined ? undefined :
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 22, 12))
+
+    T extends string ? "" :
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 22, 12))
+
+    T extends number ? 0 :
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 22, 12))
+
+    T extends boolean ? false :
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 22, 12))
+
+    never;
+
+function f10<T extends {}>(x: ZeroOf<T>) {
+>f10 : Symbol(f10, Decl(distributiveConditionalTypeConstraints.ts, 28, 10))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 30, 13))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 30, 27))
+>ZeroOf : Symbol(ZeroOf, Decl(distributiveConditionalTypeConstraints.ts, 20, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 30, 13))
+
+    let t: "" | 0 | false = x;
+>t : Symbol(t, Decl(distributiveConditionalTypeConstraints.ts, 31, 7))
+>x : Symbol(x, Decl(distributiveConditionalTypeConstraints.ts, 30, 27))
+}
+
+// Modified repro from #30152
+
+interface A { foo(): void; }
+>A : Symbol(A, Decl(distributiveConditionalTypeConstraints.ts, 32, 1))
+>foo : Symbol(A.foo, Decl(distributiveConditionalTypeConstraints.ts, 36, 13))
+
+interface B { bar(): void; }
+>B : Symbol(B, Decl(distributiveConditionalTypeConstraints.ts, 36, 28))
+>bar : Symbol(B.bar, Decl(distributiveConditionalTypeConstraints.ts, 37, 13))
+
+interface C { foo(): void, bar(): void }
+>C : Symbol(C, Decl(distributiveConditionalTypeConstraints.ts, 37, 28))
+>foo : Symbol(C.foo, Decl(distributiveConditionalTypeConstraints.ts, 38, 13))
+>bar : Symbol(C.bar, Decl(distributiveConditionalTypeConstraints.ts, 38, 26))
+
+function test1<T extends A>(y: T extends B ? number : string) {
+>test1 : Symbol(test1, Decl(distributiveConditionalTypeConstraints.ts, 38, 40))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 40, 15))
+>A : Symbol(A, Decl(distributiveConditionalTypeConstraints.ts, 32, 1))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 40, 28))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 40, 15))
+>B : Symbol(B, Decl(distributiveConditionalTypeConstraints.ts, 36, 28))
+
+    if (typeof y == 'string') {
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 40, 28))
+
+        y;  // T extends B ? number : string
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 40, 28))
+    }
+    else {
+        y;  // never
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 40, 28))
+    }
+    const newY: string | number = y;
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 47, 9))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 40, 28))
+
+    newY;  // string
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 47, 9))
+}
+
+function test2<T extends A>(y: T extends B ? string : number) {
+>test2 : Symbol(test2, Decl(distributiveConditionalTypeConstraints.ts, 49, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 51, 15))
+>A : Symbol(A, Decl(distributiveConditionalTypeConstraints.ts, 32, 1))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 51, 28))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 51, 15))
+>B : Symbol(B, Decl(distributiveConditionalTypeConstraints.ts, 36, 28))
+
+    if (typeof y == 'string') {
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 51, 28))
+
+        y;  // never
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 51, 28))
+    }
+    else {
+        y;  // T extends B ? string : number
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 51, 28))
+    }
+    const newY: string | number = y;
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 58, 9))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 51, 28))
+
+    newY;  // number 
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 58, 9))
+}
+
+function test3<T extends A>(y: T extends C ? number : string) {
+>test3 : Symbol(test3, Decl(distributiveConditionalTypeConstraints.ts, 60, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 62, 15))
+>A : Symbol(A, Decl(distributiveConditionalTypeConstraints.ts, 32, 1))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 62, 28))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 62, 15))
+>C : Symbol(C, Decl(distributiveConditionalTypeConstraints.ts, 37, 28))
+
+    if (typeof y == 'string') {
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 62, 28))
+
+        y;  // (T extends C ? number : string) & string
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 62, 28))
+    }
+    else {
+        y;  // T extends C ? number : string
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 62, 28))
+    }
+    const newY: string | number = y;
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 69, 9))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 62, 28))
+
+    newY;  // string | number
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 69, 9))
+}
+
+function test4<T extends A>(y: T extends C ? string : number) {
+>test4 : Symbol(test4, Decl(distributiveConditionalTypeConstraints.ts, 71, 1))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 73, 15))
+>A : Symbol(A, Decl(distributiveConditionalTypeConstraints.ts, 32, 1))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 73, 28))
+>T : Symbol(T, Decl(distributiveConditionalTypeConstraints.ts, 73, 15))
+>C : Symbol(C, Decl(distributiveConditionalTypeConstraints.ts, 37, 28))
+
+    if (typeof y == 'string') {
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 73, 28))
+
+        y;  // (T extends C ? string : number) & string
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 73, 28))
+    }
+    else {
+        y;  // T extends C ? string : number
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 73, 28))
+    }
+    const newY: string | number = y;
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 80, 9))
+>y : Symbol(y, Decl(distributiveConditionalTypeConstraints.ts, 73, 28))
+
+    newY;  // string | number
+>newY : Symbol(newY, Decl(distributiveConditionalTypeConstraints.ts, 80, 9))
+}
+
diff --git a/tests/baselines/reference/distributiveConditionalTypeConstraints.types b/tests/baselines/reference/distributiveConditionalTypeConstraints.types
new file mode 100644
index 0000000000000..8793a421c9782
--- /dev/null
+++ b/tests/baselines/reference/distributiveConditionalTypeConstraints.types
@@ -0,0 +1,202 @@
+//// [tests/cases/compiler/distributiveConditionalTypeConstraints.ts] ////
+
+=== distributiveConditionalTypeConstraints.ts ===
+type IsArray<T> = T extends unknown[] ? true : false;
+>IsArray : IsArray<T>
+>true : true
+>false : false
+
+function f1<T extends object>(x: IsArray<T>) {
+>f1 : <T extends object>(x: IsArray<T>) => void
+>x : IsArray<T>
+
+    let t: true = x;   // Error
+>t : true
+>true : true
+>x : boolean
+
+    let f: false = x;  // Error
+>f : false
+>false : false
+>x : boolean
+}
+
+function f2<T extends unknown[]>(x: IsArray<T>) {
+>f2 : <T extends unknown[]>(x: IsArray<T>) => void
+>x : IsArray<T>
+
+    let t: true = x;
+>t : true
+>true : true
+>x : IsArray<T>
+
+    let f: false = x;  // Error
+>f : false
+>false : false
+>x : IsArray<T>
+}
+
+function f3<T extends string[]>(x: IsArray<T>) {
+>f3 : <T extends string[]>(x: IsArray<T>) => void
+>x : IsArray<T>
+
+    let t: true = x;
+>t : true
+>true : true
+>x : IsArray<T>
+
+    let f: false = x;  // Error
+>f : false
+>false : false
+>x : IsArray<T>
+}
+
+function f4<T extends Function>(x: IsArray<T>) {
+>f4 : <T extends Function>(x: IsArray<T>) => void
+>x : IsArray<T>
+
+    let t: true = x;   // Error
+>t : true
+>true : true
+>x : IsArray<T>
+
+    let f: false = x;
+>f : false
+>false : false
+>x : IsArray<T>
+}
+
+type ZeroOf<T> =
+>ZeroOf : ZeroOf<T>
+
+    T extends null ? null :
+    T extends undefined ? undefined :
+    T extends string ? "" :
+    T extends number ? 0 :
+    T extends boolean ? false :
+>false : false
+
+    never;
+
+function f10<T extends {}>(x: ZeroOf<T>) {
+>f10 : <T extends {}>(x: ZeroOf<T>) => void
+>x : ZeroOf<T>
+
+    let t: "" | 0 | false = x;
+>t : false | "" | 0
+>false : false
+>x : false | "" | 0
+}
+
+// Modified repro from #30152
+
+interface A { foo(): void; }
+>foo : () => void
+
+interface B { bar(): void; }
+>bar : () => void
+
+interface C { foo(): void, bar(): void }
+>foo : () => void
+>bar : () => void
+
+function test1<T extends A>(y: T extends B ? number : string) {
+>test1 : <T extends A>(y: T extends B ? number : string) => void
+>y : T extends B ? number : string
+
+    if (typeof y == 'string') {
+>typeof y == 'string' : boolean
+>typeof y : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>y : T extends B ? number : string
+>'string' : "string"
+
+        y;  // T extends B ? number : string
+>y : T extends B ? number : string
+    }
+    else {
+        y;  // never
+>y : never
+    }
+    const newY: string | number = y;
+>newY : string | number
+>y : T extends B ? number : string
+
+    newY;  // string
+>newY : string
+}
+
+function test2<T extends A>(y: T extends B ? string : number) {
+>test2 : <T extends A>(y: T extends B ? string : number) => void
+>y : T extends B ? string : number
+
+    if (typeof y == 'string') {
+>typeof y == 'string' : boolean
+>typeof y : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>y : T extends B ? string : number
+>'string' : "string"
+
+        y;  // never
+>y : never
+    }
+    else {
+        y;  // T extends B ? string : number
+>y : T extends B ? string : number
+    }
+    const newY: string | number = y;
+>newY : string | number
+>y : T extends B ? string : number
+
+    newY;  // number 
+>newY : number
+}
+
+function test3<T extends A>(y: T extends C ? number : string) {
+>test3 : <T extends A>(y: T extends C ? number : string) => void
+>y : T extends C ? number : string
+
+    if (typeof y == 'string') {
+>typeof y == 'string' : boolean
+>typeof y : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>y : T extends C ? number : string
+>'string' : "string"
+
+        y;  // (T extends C ? number : string) & string
+>y : (T extends C ? number : string) & string
+    }
+    else {
+        y;  // T extends C ? number : string
+>y : T extends C ? number : string
+    }
+    const newY: string | number = y;
+>newY : string | number
+>y : string | number
+
+    newY;  // string | number
+>newY : string | number
+}
+
+function test4<T extends A>(y: T extends C ? string : number) {
+>test4 : <T extends A>(y: T extends C ? string : number) => void
+>y : T extends C ? string : number
+
+    if (typeof y == 'string') {
+>typeof y == 'string' : boolean
+>typeof y : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
+>y : T extends C ? string : number
+>'string' : "string"
+
+        y;  // (T extends C ? string : number) & string
+>y : (T extends C ? string : number) & string
+    }
+    else {
+        y;  // T extends C ? string : number
+>y : T extends C ? string : number
+    }
+    const newY: string | number = y;
+>newY : string | number
+>y : string | number
+
+    newY;  // string | number
+>newY : string | number
+}
+
diff --git a/tests/cases/compiler/distributiveConditionalTypeConstraints.ts b/tests/cases/compiler/distributiveConditionalTypeConstraints.ts
new file mode 100644
index 0000000000000..82366a73c59ef
--- /dev/null
+++ b/tests/cases/compiler/distributiveConditionalTypeConstraints.ts
@@ -0,0 +1,86 @@
+// @strict: true
+// @noEmit: true
+
+type IsArray<T> = T extends unknown[] ? true : false;
+
+function f1<T extends object>(x: IsArray<T>) {
+    let t: true = x;   // Error
+    let f: false = x;  // Error
+}
+
+function f2<T extends unknown[]>(x: IsArray<T>) {
+    let t: true = x;
+    let f: false = x;  // Error
+}
+
+function f3<T extends string[]>(x: IsArray<T>) {
+    let t: true = x;
+    let f: false = x;  // Error
+}
+
+function f4<T extends Function>(x: IsArray<T>) {
+    let t: true = x;   // Error
+    let f: false = x;
+}
+
+type ZeroOf<T> =
+    T extends null ? null :
+    T extends undefined ? undefined :
+    T extends string ? "" :
+    T extends number ? 0 :
+    T extends boolean ? false :
+    never;
+
+function f10<T extends {}>(x: ZeroOf<T>) {
+    let t: "" | 0 | false = x;
+}
+
+// Modified repro from #30152
+
+interface A { foo(): void; }
+interface B { bar(): void; }
+interface C { foo(): void, bar(): void }
+
+function test1<T extends A>(y: T extends B ? number : string) {
+    if (typeof y == 'string') {
+        y;  // T extends B ? number : string
+    }
+    else {
+        y;  // never
+    }
+    const newY: string | number = y;
+    newY;  // string
+}
+
+function test2<T extends A>(y: T extends B ? string : number) {
+    if (typeof y == 'string') {
+        y;  // never
+    }
+    else {
+        y;  // T extends B ? string : number
+    }
+    const newY: string | number = y;
+    newY;  // number 
+}
+
+function test3<T extends A>(y: T extends C ? number : string) {
+    if (typeof y == 'string') {
+        y;  // (T extends C ? number : string) & string
+    }
+    else {
+        y;  // T extends C ? number : string
+    }
+    const newY: string | number = y;
+    newY;  // string | number
+}
+
+function test4<T extends A>(y: T extends C ? string : number) {
+    if (typeof y == 'string') {
+        y;  // (T extends C ? string : number) & string
+    }
+    else {
+        y;  // T extends C ? string : number
+    }
+    const newY: string | number = y;
+    newY;  // string | number
+}