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=== tests/cases/compiler/strictTypeofUnionNarrowing.ts ===
function stringify1(anything: { toString(): string } | undefined): string {
>stringify1 : (anything: { toString(): string;} | undefined) => string
>anything : { toString(): string; } | undefined
>toString : () => string
return typeof anything === "string" ? anything.toUpperCase() : "";
>typeof anything === "string" ? anything.toUpperCase() : "" : string
>typeof anything === "string" : boolean
>typeof anything : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>anything : { toString(): string; } | undefined
>"string" : "string"
>anything.toUpperCase() : string
>anything.toUpperCase : () => string
>anything : string
>toUpperCase : () => string
>"" : ""
}
function stringify2(anything: {} | undefined): string {
>stringify2 : (anything: {} | undefined) => string
>anything : {} | undefined
return typeof anything === "string" ? anything.toUpperCase() : "";
>typeof anything === "string" ? anything.toUpperCase() : "" : string
>typeof anything === "string" : boolean
>typeof anything : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>anything : {} | undefined
>"string" : "string"
>anything.toUpperCase() : string
>anything.toUpperCase : () => string
>anything : string
>toUpperCase : () => string
>"" : ""
}
function stringify3(anything: unknown | undefined): string { // should simplify to just `unknown` which should narrow fine
>stringify3 : (anything: unknown | undefined) => string
>anything : unknown
return typeof anything === "string" ? anything.toUpperCase() : "";
>typeof anything === "string" ? anything.toUpperCase() : "" : string
>typeof anything === "string" : boolean
>typeof anything : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>anything : unknown
>"string" : "string"
>anything.toUpperCase() : string
>anything.toUpperCase : () => string
>anything : string
>toUpperCase : () => string
>"" : ""
}
function stringify4(anything: { toString?(): string } | undefined): string {
>stringify4 : (anything: { toString?(): string;} | undefined) => string
>anything : { toString?(): string; } | undefined
>toString : (() => string) | undefined
return typeof anything === "string" ? anything.toUpperCase() : "";
>typeof anything === "string" ? anything.toUpperCase() : "" : string
>typeof anything === "string" : boolean
>typeof anything : "string" | "number" | "bigint" | "boolean" | "symbol" | "undefined" | "object" | "function"
>anything : { toString?(): string; } | undefined
>"string" : "string"
>anything.toUpperCase() : string
>anything.toUpperCase : () => string
>anything : string
>toUpperCase : () => string
>"" : ""
}
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