Track tuple type recursion in inferFromObjectTypes

src/compiler/checker.ts

@@ -18127,7 +18127,7 @@ namespace ts {
         }
 
         function inferTypes(inferences: InferenceInfo[], originalSource: Type, originalTarget: Type, priority: InferencePriority = 0, contravariant = false) {
-            let symbolStack: Symbol[];
+            let symbolOrTypeStack: (Symbol | Type)[];
             let visited: Map<number>;
             let bivariant = false;
             let propagationType: Type;
@@ -18566,15 +18566,15 @@ namespace ts {
                 // its symbol with the instance side which would lead to false positives.
                 const isNonConstructorObject = target.flags & TypeFlags.Object &&
                     !(getObjectFlags(target) & ObjectFlags.Anonymous && target.symbol && target.symbol.flags & SymbolFlags.Class);
-                const symbol = isNonConstructorObject ? target.symbol : undefined;
-                if (symbol) {
-                    if (contains(symbolStack, symbol)) {
+                const symbolOrType = isNonConstructorObject ? isTupleType(target) ? target.target : target.symbol : undefined;
+                if (symbolOrType) {
+                    if (contains(symbolOrTypeStack, symbolOrType)) {
                         inferencePriority = InferencePriority.Circularity;
                         return;
                     }
-                    (symbolStack || (symbolStack = [])).push(symbol);
+                    (symbolOrTypeStack || (symbolOrTypeStack = [])).push(symbolOrType);
                     inferFromObjectTypesWorker(source, target);
-                    symbolStack.pop();
+                    symbolOrTypeStack.pop();
                 }
                 else {
                     inferFromObjectTypesWorker(source, target);

tests/baselines/reference/recursiveTupleTypeInference.errors.txt

@@ -0,0 +1,36 @@
+tests/cases/compiler/recursiveTupleTypeInference.ts(23,5): error TS2345: Argument of type '{ b: A; }' is not assignable to parameter of type 'G<{ b: unknown; }>'.
+  Types of property 'b' are incompatible.
+    Type 'A' is not assignable to type '[[[[[[[[[[[[any, "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"]'.
+      Type '"number"' is not assignable to type '[[[[[[[[[[[[any, "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"]'.
+
+
+==== tests/cases/compiler/recursiveTupleTypeInference.ts (1 errors) ====
+    // Repro from #37475
+
+    export type A = "number" | "null" | A[];
+
+    export type F<T> = null extends T
+        ? [F<NonNullable<T>>, "null"]
+        : T extends number
+        ? "number"
+        : never;
+
+    export type G<T> = { [k in keyof T]: F<T[k]> };
+
+    interface K {
+        b: number | null;
+    }
+
+    const gK: { [key in keyof K]: A } = { b: ["number", "null"] };
+
+    function foo<T>(g: G<T>): T {
+        return {} as any;
+    }
+
+    foo(gK);
+        ~~
+!!! error TS2345: Argument of type '{ b: A; }' is not assignable to parameter of type 'G<{ b: unknown; }>'.
+!!! error TS2345:   Types of property 'b' are incompatible.
+!!! error TS2345:     Type 'A' is not assignable to type '[[[[[[[[[[[[any, "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"]'.
+!!! error TS2345:       Type '"number"' is not assignable to type '[[[[[[[[[[[[any, "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"], "null"]'.
+

tests/baselines/reference/recursiveTupleTypeInference.js

@@ -0,0 +1,35 @@
+//// [recursiveTupleTypeInference.ts]
+// Repro from #37475
+
+export type A = "number" | "null" | A[];
+
+export type F<T> = null extends T
+    ? [F<NonNullable<T>>, "null"]
+    : T extends number
+    ? "number"
+    : never;
+
+export type G<T> = { [k in keyof T]: F<T[k]> };
+
+interface K {
+    b: number | null;
+}
+
+const gK: { [key in keyof K]: A } = { b: ["number", "null"] };
+
+function foo<T>(g: G<T>): T {
+    return {} as any;
+}
+
+foo(gK);
+
+
+//// [recursiveTupleTypeInference.js]
+"use strict";
+// Repro from #37475
+exports.__esModule = true;
+var gK = { b: ["number", "null"] };
+function foo(g) {
+    return {};
+}
+foo(gK);

tests/baselines/reference/recursiveTupleTypeInference.symbols

@@ -0,0 +1,61 @@
+=== tests/cases/compiler/recursiveTupleTypeInference.ts ===
+// Repro from #37475
+
+export type A = "number" | "null" | A[];
+>A : Symbol(A, Decl(recursiveTupleTypeInference.ts, 0, 0))
+>A : Symbol(A, Decl(recursiveTupleTypeInference.ts, 0, 0))
+
+export type F<T> = null extends T
+>F : Symbol(F, Decl(recursiveTupleTypeInference.ts, 2, 40))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 4, 14))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 4, 14))
+
+    ? [F<NonNullable<T>>, "null"]
+>F : Symbol(F, Decl(recursiveTupleTypeInference.ts, 2, 40))
+>NonNullable : Symbol(NonNullable, Decl(lib.es5.d.ts, --, --))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 4, 14))
+
+    : T extends number
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 4, 14))
+
+    ? "number"
+    : never;
+
+export type G<T> = { [k in keyof T]: F<T[k]> };
+>G : Symbol(G, Decl(recursiveTupleTypeInference.ts, 8, 12))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 10, 14))
+>k : Symbol(k, Decl(recursiveTupleTypeInference.ts, 10, 22))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 10, 14))
+>F : Symbol(F, Decl(recursiveTupleTypeInference.ts, 2, 40))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 10, 14))
+>k : Symbol(k, Decl(recursiveTupleTypeInference.ts, 10, 22))
+
+interface K {
+>K : Symbol(K, Decl(recursiveTupleTypeInference.ts, 10, 47))
+
+    b: number | null;
+>b : Symbol(K.b, Decl(recursiveTupleTypeInference.ts, 12, 13))
+}
+
+const gK: { [key in keyof K]: A } = { b: ["number", "null"] };
+>gK : Symbol(gK, Decl(recursiveTupleTypeInference.ts, 16, 5))
+>key : Symbol(key, Decl(recursiveTupleTypeInference.ts, 16, 13))
+>K : Symbol(K, Decl(recursiveTupleTypeInference.ts, 10, 47))
+>A : Symbol(A, Decl(recursiveTupleTypeInference.ts, 0, 0))
+>b : Symbol(b, Decl(recursiveTupleTypeInference.ts, 16, 37))
+
+function foo<T>(g: G<T>): T {
+>foo : Symbol(foo, Decl(recursiveTupleTypeInference.ts, 16, 62))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 18, 13))
+>g : Symbol(g, Decl(recursiveTupleTypeInference.ts, 18, 16))
+>G : Symbol(G, Decl(recursiveTupleTypeInference.ts, 8, 12))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 18, 13))
+>T : Symbol(T, Decl(recursiveTupleTypeInference.ts, 18, 13))
+
+    return {} as any;
+}
+
+foo(gK);
+>foo : Symbol(foo, Decl(recursiveTupleTypeInference.ts, 16, 62))
+>gK : Symbol(gK, Decl(recursiveTupleTypeInference.ts, 16, 5))
+

tests/baselines/reference/recursiveTupleTypeInference.types

@@ -0,0 +1,46 @@
+=== tests/cases/compiler/recursiveTupleTypeInference.ts ===
+// Repro from #37475
+
+export type A = "number" | "null" | A[];
+>A : A
+
+export type F<T> = null extends T
+>F : F<T>
+>null : null
+
+    ? [F<NonNullable<T>>, "null"]
+    : T extends number
+    ? "number"
+    : never;
+
+export type G<T> = { [k in keyof T]: F<T[k]> };
+>G : G<T>
+
+interface K {
+    b: number | null;
+>b : number | null
+>null : null
+}
+
+const gK: { [key in keyof K]: A } = { b: ["number", "null"] };
+>gK : { b: A; }
+>{ b: ["number", "null"] } : { b: ("number" | "null")[]; }
+>b : ("number" | "null")[]
+>["number", "null"] : ("number" | "null")[]
+>"number" : "number"
+>"null" : "null"
+
+function foo<T>(g: G<T>): T {
+>foo : <T>(g: G<T>) => T
+>g : G<T>
+
+    return {} as any;
+>{} as any : any
+>{} : {}
+}
+
+foo(gK);
+>foo(gK) : { b: unknown; }
+>foo : <T>(g: G<T>) => T
+>gK : { b: A; }
+

tests/cases/compiler/recursiveTupleTypeInference.ts

@@ -0,0 +1,25 @@
+// @strict: true
+
+// Repro from #37475
+
+export type A = "number" | "null" | A[];
+
+export type F<T> = null extends T
+    ? [F<NonNullable<T>>, "null"]
+    : T extends number
+    ? "number"
+    : never;
+
+export type G<T> = { [k in keyof T]: F<T[k]> };
+
+interface K {
+    b: number | null;
+}
+
+const gK: { [key in keyof K]: A } = { b: ["number", "null"] };
+
+function foo<T>(g: G<T>): T {
+    return {} as any;
+}
+
+foo(gK);