Add tests

tests/cases/conformance/types/rest/genericRestParameters3.ts

@@ -0,0 +1,56 @@
+// @strict: true
+// @declaration: true
+
+declare let f1: (x: string, ...args: [string] | [number, boolean]) => void;
+declare let f2: (x: string, y: string) => void;
+declare let f3: (x: string, y: number, z: boolean) => void;
+declare let f4: (...args: [string, string] | [string, number, boolean]) => void;
+
+declare const tt: [string] | [number, boolean];
+
+f1("foo", "abc");
+f1("foo", 10, true);
+f1("foo", ...tt);
+f1("foo", 10);  // Error
+f1("foo");  // Error
+
+f2 = f1;
+f3 = f1;
+f4 = f1;  // Error, misaligned complex rest types
+f1 = f2;  // Error
+f1 = f3;  // Error
+f1 = f4;  // Error, misaligned complex rest types
+
+// Repro from #26110
+
+interface CoolArray<E> extends Array<E> { 
+    hello: number;
+}
+
+declare function foo<T extends any[]>(cb: (...args: T) => void): void;
+
+foo<CoolArray<any>>();     // Error
+foo<CoolArray<any>>(100);  // Error
+foo<CoolArray<any>>(foo);  // Error
+
+function bar<T extends any[]>(...args: T): T {
+    return args;
+}
+
+let a = bar(10, 20);
+let b = bar<CoolArray<number>>(10, 20);  // Error
+
+declare function baz<T>(...args: CoolArray<T>): void;
+declare const ca: CoolArray<number>;
+
+baz();       // Error
+baz(1);      // Error
+baz(1, 2);   // Error
+baz(...ca);  // Error
+
+// Repro from #26491
+
+declare function hmm<A extends [] | [number, string]>(...args: A): void;
+hmm(); // okay, A = []
+hmm(1, "s"); // okay, A = [1, "s"]
+hmm("what"); // no error?  A = [] | [number, string] ?