Port TypeScript PR #60321: Error on too many parameters for iterator method

internal/checker/checker.go

@@ -481,7 +481,7 @@ const (
 	IterationUseAsyncYieldStar           = IterationUseAllowsSyncIterablesFlag | IterationUseAllowsAsyncIterablesFlag | IterationUseYieldStarFlag
 	IterationUseGeneratorReturnType      = IterationUseAllowsSyncIterablesFlag
 	IterationUseAsyncGeneratorReturnType = IterationUseAllowsAsyncIterablesFlag
-	IterationUseCacheFlags               = IterationUseAllowsSyncIterablesFlag | IterationUseAllowsAsyncIterablesFlag | IterationUseForOfFlag | IterationUseReportError
+	IterationUseCacheFlags               = IterationUseAllowsSyncIterablesFlag | IterationUseAllowsAsyncIterablesFlag | IterationUseForOfFlag | IterationUseYieldStarFlag | IterationUseSpreadFlag | IterationUseDestructuringFlag | IterationUseReportError
 )
 
 type IterationTypes struct {
@@ -5905,7 +5905,10 @@ func (c *Checker) getIterationTypesOfIterable(t *Type, use IterationUse, errorNo
 		return cached
 	}
 	result := c.getIterationTypesOfIterableWorker(t, use, errorNode)
-	c.iterationTypesCache[key] = result
+	// Don't cache empty results when error reporting is requested, to ensure errors are reported for each call site
+	if result.hasTypes() || errorNode == nil {
+		c.iterationTypesCache[key] = result
+	}
 	return result
 }
 
@@ -6065,10 +6068,18 @@ func (c *Checker) getIterationTypesOfIterableSlow(t *Type, r *IterationTypesReso
 		if IsTypeAny(methodType) {
 			return IterationTypes{c.anyType, c.anyType, c.anyType}
 		}
-		if signatures := c.getSignaturesOfType(methodType, SignatureKindCall); len(signatures) != 0 {
-			iteratorType := c.getIntersectionType(core.Map(signatures, c.getReturnTypeOfSignature))
-			return c.getIterationTypesOfIteratorWorker(iteratorType, r, errorNode, diagnosticOutput)
+		allSignatures := c.getSignaturesOfType(methodType, SignatureKindCall)
+		validSignatures := core.Filter(allSignatures, func(sig *Signature) bool {
+			return c.getMinArgumentCount(sig) == 0
+		})
+		if len(validSignatures) == 0 {
+			if errorNode != nil && len(allSignatures) > 0 {
+				c.checkTypeAssignableToEx(t, r.getGlobalIterableType(), errorNode, nil /*headMessage*/, diagnosticOutput)
+			}
+			return IterationTypes{}
 		}
+		iteratorType := c.getIntersectionType(core.Map(validSignatures, c.getReturnTypeOfSignature))
+		return c.getIterationTypesOfIteratorWorker(iteratorType, r, errorNode, diagnosticOutput)
 	}
 	return IterationTypes{}
 }

testdata/baselines/reference/submodule/compiler/asyncIteratorExtraParameters.errors.txt

@@ -0,0 +1,32 @@
+asyncIteratorExtraParameters.ts(11,27): error TS2504: Type '{ [Symbol.asyncIterator](_: number): AsyncGenerator<number, void, unknown>; }' must have a '[Symbol.asyncIterator]()' method that returns an async iterator.
+asyncIteratorExtraParameters.ts(13,12): error TS2504: Type '{ [Symbol.asyncIterator](_: number): AsyncGenerator<number, void, unknown>; }' must have a '[Symbol.asyncIterator]()' method that returns an async iterator.
+
+
+==== asyncIteratorExtraParameters.ts (2 errors) ====
+    // https://github.com/microsoft/TypeScript/issues/57130
+    const iter = {
+        async *[Symbol.asyncIterator](_: number) {
+            yield 0;
+        }
+    };
+
+    declare function g(...args: any): any;
+
+    async function* f() {
+        for await (const _ of iter);
+                              ~~~~
+!!! error TS2504: Type '{ [Symbol.asyncIterator](_: number): AsyncGenerator<number, void, unknown>; }' must have a '[Symbol.asyncIterator]()' method that returns an async iterator.
+!!! related TS2322 asyncIteratorExtraParameters.ts:11:27: Type '{ [Symbol.asyncIterator](_: number): AsyncGenerator<number, void, unknown>; }' is not assignable to type 'AsyncIterable<T, TReturn, TNext>'.
+  Types of property '[Symbol.asyncIterator]' are incompatible.
+    Type '(_: number) => AsyncGenerator<number, void, unknown>' is not assignable to type '() => AsyncIterator<T, TReturn, TNext>'.
+      Target signature provides too few arguments. Expected 1 or more, but got 0.
+
+        yield* iter;
+               ~~~~
+!!! error TS2504: Type '{ [Symbol.asyncIterator](_: number): AsyncGenerator<number, void, unknown>; }' must have a '[Symbol.asyncIterator]()' method that returns an async iterator.
+!!! related TS2322 asyncIteratorExtraParameters.ts:13:12: Type '{ [Symbol.asyncIterator](_: number): AsyncGenerator<number, void, unknown>; }' is not assignable to type 'AsyncIterable<T, TReturn, TNext>'.
+  Types of property '[Symbol.asyncIterator]' are incompatible.
+    Type '(_: number) => AsyncGenerator<number, void, unknown>' is not assignable to type '() => AsyncIterator<T, TReturn, TNext>'.
+      Target signature provides too few arguments. Expected 1 or more, but got 0.
+    }
+

testdata/baselines/reference/submodule/compiler/iteratorExtraParameters.errors.txt

@@ -0,0 +1,50 @@
+iteratorExtraParameters.ts(11,21): error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+iteratorExtraParameters.ts(13,12): error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+iteratorExtraParameters.ts(15,9): error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+iteratorExtraParameters.ts(17,10): error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+
+
+==== iteratorExtraParameters.ts (4 errors) ====
+    // https://github.com/microsoft/TypeScript/issues/57130
+    const iter = {
+        *[Symbol.iterator](_: number) {
+            yield 0;
+        }
+    };
+
+    declare function g(...args: any): any;
+
+    function* f() {
+        for (const _ of iter);
+                        ~~~~
+!!! error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+!!! related TS2322 iteratorExtraParameters.ts:11:21: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' is not assignable to type 'Iterable<T, TReturn, TNext>'.
+  Types of property '[Symbol.iterator]' are incompatible.
+    Type '(_: number) => Generator<number, void, unknown>' is not assignable to type '() => Iterator<T, TReturn, TNext>'.
+      Target signature provides too few arguments. Expected 1 or more, but got 0.
+
+        yield* iter;
+               ~~~~
+!!! error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+!!! related TS2322 iteratorExtraParameters.ts:13:12: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' is not assignable to type 'Iterable<T, TReturn, TNext>'.
+  Types of property '[Symbol.iterator]' are incompatible.
+    Type '(_: number) => Generator<number, void, unknown>' is not assignable to type '() => Iterator<T, TReturn, TNext>'.
+      Target signature provides too few arguments. Expected 1 or more, but got 0.
+
+        [...iter]
+            ~~~~
+!!! error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+!!! related TS2322 iteratorExtraParameters.ts:15:9: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' is not assignable to type 'Iterable<T, TReturn, TNext>'.
+  Types of property '[Symbol.iterator]' are incompatible.
+    Type '(_: number) => Generator<number, void, unknown>' is not assignable to type '() => Iterator<T, TReturn, TNext>'.
+      Target signature provides too few arguments. Expected 1 or more, but got 0.
+
+        g(...iter);
+             ~~~~
+!!! error TS2488: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' must have a '[Symbol.iterator]()' method that returns an iterator.
+!!! related TS2322 iteratorExtraParameters.ts:17:10: Type '{ [Symbol.iterator](_: number): Generator<number, void, unknown>; }' is not assignable to type 'Iterable<T, TReturn, TNext>'.
+  Types of property '[Symbol.iterator]' are incompatible.
+    Type '(_: number) => Generator<number, void, unknown>' is not assignable to type '() => Iterator<T, TReturn, TNext>'.
+      Target signature provides too few arguments. Expected 1 or more, but got 0.
+    }
+

testdata/baselines/reference/submodule/compiler/omittedExpressionForOfLoop.errors.txt

@@ -1,9 +1,10 @@
 omittedExpressionForOfLoop.ts(1,19): error TS2304: Cannot find name 'doesNotExist'.
 omittedExpressionForOfLoop.ts(4,19): error TS18050: The value 'undefined' cannot be used here.
 omittedExpressionForOfLoop.ts(7,12): error TS2488: Type 'never' must have a '[Symbol.iterator]()' method that returns an iterator.
+omittedExpressionForOfLoop.ts(10,12): error TS2488: Type 'never' must have a '[Symbol.iterator]()' method that returns an iterator.
 
 
-==== omittedExpressionForOfLoop.ts (3 errors) ====
+==== omittedExpressionForOfLoop.ts (4 errors) ====
     for (const [,] of doesNotExist) {
                       ~~~~~~~~~~~~
 !!! error TS2304: Cannot find name 'doesNotExist'.
@@ -20,4 +21,6 @@ omittedExpressionForOfLoop.ts(7,12): error TS2488: Type 'never' must have a '[Sy
     }
 
     for (const [] of []) {
+               ~~
+!!! error TS2488: Type 'never' must have a '[Symbol.iterator]()' method that returns an iterator.
     }

testdata/baselines/reference/submodule/conformance/for-of16.errors.txt

@@ -1,7 +1,8 @@
 for-of16.ts(8,11): error TS2488: Type 'MyStringIterator' must have a '[Symbol.iterator]()' method that returns an iterator.
+for-of16.ts(10,11): error TS2488: Type 'MyStringIterator' must have a '[Symbol.iterator]()' method that returns an iterator.
 
 
-==== for-of16.ts (1 errors) ====
+==== for-of16.ts (2 errors) ====
     class MyStringIterator {
         [Symbol.iterator]() {
             return this;
@@ -14,4 +15,7 @@ for-of16.ts(8,11): error TS2488: Type 'MyStringIterator' must have a '[Symbol.it
 !!! error TS2488: Type 'MyStringIterator' must have a '[Symbol.iterator]()' method that returns an iterator.
 !!! related TS2489 for-of16.ts:8:11: An iterator must have a 'next()' method.
 
-    for (v of new MyStringIterator) { } // Should still fail (related errors should still be shown even though type is cached).
+    for (v of new MyStringIterator) { } // Should still fail (related errors should still be shown even though type is cached).
+              ~~~~~~~~~~~~~~~~~~~~
+!!! error TS2488: Type 'MyStringIterator' must have a '[Symbol.iterator]()' method that returns an iterator.
+!!! related TS2489 for-of16.ts:10:11: An iterator must have a 'next()' method.