diff --git a/tests/baselines/reference/intersectionWithUnionConstraint.errors.txt b/tests/baselines/reference/intersectionWithUnionConstraint.errors.txt
index 9bdfc6f30f9..97ed1cf4895 100644
--- a/tests/baselines/reference/intersectionWithUnionConstraint.errors.txt
+++ b/tests/baselines/reference/intersectionWithUnionConstraint.errors.txt
@@ -80,4 +80,9 @@ tests/cases/conformance/types/intersection/intersectionWithUnionConstraint.ts(12
     
     type UnexpectedError<T extends PropertyKey> = T
     type NoErrorHere<T extends PropertyKey> = T
+    
+    // Repro from #30331
+    
+    type a<T> = T extends Array<infer U> ? U : never;
+    type b<T> = { [K in a<T> & keyof T ]: 42 };
     
\ No newline at end of file
diff --git a/tests/baselines/reference/intersectionWithUnionConstraint.js b/tests/baselines/reference/intersectionWithUnionConstraint.js
index fc3e50309c6..00330d23f6d 100644
--- a/tests/baselines/reference/intersectionWithUnionConstraint.js
+++ b/tests/baselines/reference/intersectionWithUnionConstraint.js
@@ -33,6 +33,11 @@ type Example<T, U> = { [K in keyof T]: K extends keyof U ? UnexpectedError<K> :
 
 type UnexpectedError<T extends PropertyKey> = T
 type NoErrorHere<T extends PropertyKey> = T
+
+// Repro from #30331
+
+type a<T> = T extends Array<infer U> ? U : never;
+type b<T> = { [K in a<T> & keyof T ]: 42 };
 
 
 //// [intersectionWithUnionConstraint.js]
diff --git a/tests/baselines/reference/intersectionWithUnionConstraint.symbols b/tests/baselines/reference/intersectionWithUnionConstraint.symbols
index f481a5c5185..1ef1f8435d9 100644
--- a/tests/baselines/reference/intersectionWithUnionConstraint.symbols
+++ b/tests/baselines/reference/intersectionWithUnionConstraint.symbols
@@ -112,3 +112,21 @@ type NoErrorHere<T extends PropertyKey> = T
 >PropertyKey : Symbol(PropertyKey, Decl(lib.es5.d.ts, --, --))
 >T : Symbol(T, Decl(intersectionWithUnionConstraint.ts, 33, 17))
 
+// Repro from #30331
+
+type a<T> = T extends Array<infer U> ? U : never;
+>a : Symbol(a, Decl(intersectionWithUnionConstraint.ts, 33, 43))
+>T : Symbol(T, Decl(intersectionWithUnionConstraint.ts, 37, 7))
+>T : Symbol(T, Decl(intersectionWithUnionConstraint.ts, 37, 7))
+>Array : Symbol(Array, Decl(lib.es5.d.ts, --, --), Decl(lib.es5.d.ts, --, --))
+>U : Symbol(U, Decl(intersectionWithUnionConstraint.ts, 37, 33))
+>U : Symbol(U, Decl(intersectionWithUnionConstraint.ts, 37, 33))
+
+type b<T> = { [K in a<T> & keyof T ]: 42 };
+>b : Symbol(b, Decl(intersectionWithUnionConstraint.ts, 37, 49))
+>T : Symbol(T, Decl(intersectionWithUnionConstraint.ts, 38, 7))
+>K : Symbol(K, Decl(intersectionWithUnionConstraint.ts, 38, 15))
+>a : Symbol(a, Decl(intersectionWithUnionConstraint.ts, 33, 43))
+>T : Symbol(T, Decl(intersectionWithUnionConstraint.ts, 38, 7))
+>T : Symbol(T, Decl(intersectionWithUnionConstraint.ts, 38, 7))
+
diff --git a/tests/baselines/reference/intersectionWithUnionConstraint.types b/tests/baselines/reference/intersectionWithUnionConstraint.types
index 126154a4968..0f9e9974bed 100644
--- a/tests/baselines/reference/intersectionWithUnionConstraint.types
+++ b/tests/baselines/reference/intersectionWithUnionConstraint.types
@@ -84,3 +84,11 @@ type UnexpectedError<T extends PropertyKey> = T
 type NoErrorHere<T extends PropertyKey> = T
 >NoErrorHere : T
 
+// Repro from #30331
+
+type a<T> = T extends Array<infer U> ? U : never;
+>a : a<T>
+
+type b<T> = { [K in a<T> & keyof T ]: 42 };
+>b : b<T>
+