swc/crates/swc_ecma_parser/tests/tsc/controlFlowForStatement.ts

let cond: boolean;
function a() {
    let x: string | number | boolean;
    for (x = ""; cond; x = 5) {
        x; // string | number
    }
}
function b() {
    let x: string | number | boolean;
    for (x = 5; cond; x = x.length) {
        x; // number
        x = "";
    }
}
function c() {
    let x: string | number | boolean;
    for (x = 5; x = x.toExponential(); x = 5) {
        x; // string
    }
}
function d() {
    let x: string | number | boolean;
    for (x = ""; typeof x === "string"; x = 5) {
        x; // string
    }
}
function e() {
    let x: string | number | boolean | RegExp;
    for (x = "" || 0; typeof x !== "string"; x = "" || true) {
        x; // number | boolean
    }
}
function f() {
    let x: string | number | boolean;
    for (; typeof x !== "string";) {
        x; // number | boolean
        if (typeof x === "number") break;
        x = undefined;
    }
    x; // string | number
}