Test that `typeof x === 'random' as string`: 1. Does not issue an error. 2. Does not narrow.
201 lines
8 KiB
Plaintext
201 lines
8 KiB
Plaintext
=== tests/cases/conformance/expressions/typeGuards/typeGuardsInRightOperandOfOrOrOperator.ts ===
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// In the right operand of a || operation,
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// the type of a variable or parameter is narrowed by any type guard in the left operand when false,
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// provided the right operand contains no assignments to the variable or parameter.
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function foo(x: number | string) {
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>foo : (x: string | number) => boolean
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>x : string | number
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return typeof x !== "string" || x.length === 10; // string
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>typeof x !== "string" || x.length === 10 : boolean
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>typeof x !== "string" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : string | number
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>"string" : "string"
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>x.length === 10 : boolean
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>x.length : number
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>x : string
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>length : number
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>10 : 10
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}
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function foo2(x: number | string) {
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>foo2 : (x: string | number) => number | true
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>x : string | number
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// modify x in right hand operand
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return typeof x !== "string" || ((x = 10) || x); // string | number
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>typeof x !== "string" || ((x = 10) || x) : number | true
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>typeof x !== "string" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : string | number
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>"string" : "string"
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>((x = 10) || x) : number
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>(x = 10) || x : number
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>(x = 10) : 10
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>x = 10 : 10
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>x : string | number
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>10 : 10
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>x : number
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}
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function foo3(x: number | string) {
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>foo3 : (x: string | number) => string | true
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>x : string | number
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// modify x in right hand operand with string type itself
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return typeof x !== "string" || ((x = "hello") || x); // string | number
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>typeof x !== "string" || ((x = "hello") || x) : string | true
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>typeof x !== "string" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : string | number
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>"string" : "string"
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>((x = "hello") || x) : string
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>(x = "hello") || x : string
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>(x = "hello") : "hello"
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>x = "hello" : "hello"
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>x : string | number
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>"hello" : "hello"
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>x : string
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}
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function foo4(x: number | string | boolean) {
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>foo4 : (x: string | number | boolean) => boolean
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>x : string | number | boolean
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return typeof x === "string" // string | number | boolean
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>typeof x === "string" // string | number | boolean || typeof x === "number" // number | boolean || x : boolean
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>typeof x === "string" // string | number | boolean || typeof x === "number" : boolean
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>typeof x === "string" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : string | number | boolean
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>"string" : "string"
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|| typeof x === "number" // number | boolean
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>typeof x === "number" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : number | boolean
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>"number" : "number"
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|| x; // boolean
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>x : boolean
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}
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function foo5(x: number | string | boolean) {
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>foo5 : (x: string | number | boolean) => number | boolean
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>x : string | number | boolean
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// usage of x or assignment to separate variable shouldn't cause narrowing of type to stop
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var b: number | boolean;
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>b : number | boolean
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return typeof x === "string" // string | number | boolean
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>typeof x === "string" // string | number | boolean || ((b = x) || (typeof x === "number" // number | boolean || x)) : number | boolean
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>typeof x === "string" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : string | number | boolean
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>"string" : "string"
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|| ((b = x) || (typeof x === "number" // number | boolean
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>((b = x) || (typeof x === "number" // number | boolean || x)) : number | boolean
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>(b = x) || (typeof x === "number" // number | boolean || x) : number | boolean
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>(b = x) : number | boolean
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>b = x : number | boolean
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>b : number | boolean
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>x : number | boolean
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>(typeof x === "number" // number | boolean || x) : boolean
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>typeof x === "number" // number | boolean || x : boolean
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>typeof x === "number" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : number | boolean
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>"number" : "number"
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|| x)); // boolean
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>x : boolean
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}
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function foo6(x: number | string | boolean) {
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>foo6 : (x: string | number | boolean) => boolean
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>x : string | number | boolean
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// Mixing typeguard
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return typeof x === "string" // string | number | boolean
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>typeof x === "string" // string | number | boolean || (typeof x !== "number" // number | boolean ? x // boolean : x === 10) : boolean
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>typeof x === "string" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : string | number | boolean
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>"string" : "string"
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|| (typeof x !== "number" // number | boolean
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>(typeof x !== "number" // number | boolean ? x // boolean : x === 10) : boolean
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>typeof x !== "number" // number | boolean ? x // boolean : x === 10 : boolean
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>typeof x !== "number" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : number | boolean
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>"number" : "number"
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? x // boolean
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>x : boolean
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: x === 10) // number
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>x === 10 : boolean
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>x : number
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>10 : 10
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}
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function foo7(x: number | string | boolean) {
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>foo7 : (x: string | number | boolean) => string | number | true
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>x : string | number | boolean
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var y: number| boolean | string;
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>y : string | number | boolean
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var z: number| boolean | string;
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>z : string | number | boolean
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// Mixing typeguard narrowing
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return typeof x === "string"
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>typeof x === "string" || ((z = x) // number | boolean || (typeof x === "number" // change value of x ? ((x = 10) && x.toString()) // number | boolean | string // do not change value : ((y = x) && x.toString()))) : string | number | true
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>typeof x === "string" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : string | number | boolean
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>"string" : "string"
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|| ((z = x) // number | boolean
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>((z = x) // number | boolean || (typeof x === "number" // change value of x ? ((x = 10) && x.toString()) // number | boolean | string // do not change value : ((y = x) && x.toString()))) : string | number | true
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>(z = x) // number | boolean || (typeof x === "number" // change value of x ? ((x = 10) && x.toString()) // number | boolean | string // do not change value : ((y = x) && x.toString())) : string | number | true
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>(z = x) : number | boolean
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>z = x : number | boolean
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>z : string | number | boolean
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>x : number | boolean
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|| (typeof x === "number"
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>(typeof x === "number" // change value of x ? ((x = 10) && x.toString()) // number | boolean | string // do not change value : ((y = x) && x.toString())) : string
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>typeof x === "number" // change value of x ? ((x = 10) && x.toString()) // number | boolean | string // do not change value : ((y = x) && x.toString()) : string
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>typeof x === "number" : boolean
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>typeof x : "string" | "number" | "boolean" | "symbol" | "undefined" | "object" | "function"
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>x : number | boolean
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>"number" : "number"
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// change value of x
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? ((x = 10) && x.toString()) // number | boolean | string
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>((x = 10) && x.toString()) : string
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>(x = 10) && x.toString() : string
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>(x = 10) : 10
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>x = 10 : 10
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>x : string | number | boolean
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>10 : 10
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>x.toString() : string
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>x.toString : (radix?: number) => string
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>x : number
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>toString : (radix?: number) => string
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// do not change value
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: ((y = x) && x.toString()))); // number | boolean | string
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>((y = x) && x.toString()) : string
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>(y = x) && x.toString() : string
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>(y = x) : boolean
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>y = x : boolean
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>y : string | number | boolean
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>x : boolean
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>x.toString() : string
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>x.toString : () => string
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>x : boolean
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>toString : () => string
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}
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