tsc crashes resolving a type of computed property in destructiring assignment

[pablobirukov]

TypeScript Version: 3.1.0-dev.20180809, 3.0.1

Search Terms:
Cannot read property 'charCodeAt' of undefined

Code

interface Limit1 {
 propName: { min: number; max: number };
}
interface Limit2 {
 propName: { min: number; max: number };
}

type Limit = Limit1 | Limit2; // should be Union type

export interface Meta {
 propName: "propName";
}

function foo (meta: Meta, limits: Limit): void {
 const {
 [`propName`]: { min: minBonus, max: maxBonus }, // should be computed
 } = limits;
}

Expected behavior:
No crash, code compiled

Actual behavior:

Cannot read property 'charCodeAt' of undefined

.../node_modules/typescript/lib/tsc.js:68035
 throw e;
 ^
TypeError: Cannot read property 'charCodeAt' of undefined

at isLateBoundName (.../node_modules/typescript/lib/tsc.js:28756:25)

at createUnionOrIntersectionProperty (.../node_modules/typescript/lib/tsc.js:29638:38)

at getUnionOrIntersectionProperty (.../node_modules/typescript/lib/tsc.js:29699:28)

at getPropertyOfUnionOrIntersectionType (.../node_modules/typescript/lib/tsc.js:29707:28)

at getPropertyOfType (.../node_modules/typescript/lib/tsc.js:29727:24)

at checkVariableLikeDeclaration (.../node_modules/typescript/lib/tsc.js:43025:36)

at checkBindingElement (.../node_modules/typescript/lib/tsc.js:43123:20)

at checkSourceElement (.../node_modules/typescript/lib/tsc.js:44827:28)

at Object.forEach (.../node_modules/typescript/lib/tsc.js:168:30)

at checkVariableLikeDeclaration (.../node_modules/typescript/lib/tsc.js:43036:20)

Playground Link:

Note, that the code is not compiled

declare const ab: { n: number } | { n: string };
const { [`n`]: n } = ab;

checkVariableLikeDeclaration calls getPropertyOfType using getTextOfPropertyName(name), but that is undefined for a computed name. (See #18217 comment in getTextOfPropertyName.) To do this properly we need a function that can find a property for an indexed access. That could also fix #26328.

[martpie]

Andy (Andrewkraft) (@Andy-MS) Has it been released yet? I am facing this issue too.

Or can you recommend a way to mitigate it in the meantime?

Yes, should be released in typescript@next.