Maximum call stack size exceeded if the variable is used in a condition before its declaration using property access #45830
Description
Bug Report
🔎 Search Terms
- Maximum call stack size exceeded
- property access call
🕗 Version & Regression Information
Works on 4.3.5, crashes on 4.4.0-beta, 4.4.1-rc, 4.4.2, 4.4.3, 4.5.0-dev.20210910.
⏯ Playground Link
Playground link with relevant code
💻 Code
const obj = {
fn: () => true
};
if (a) { } // crashes if `a` is used in the condition
const a = obj.fn();There will be no crash if a is declared without accessing the obj property
const obj = {
fn: () => true
};
const callFn = () => obj.fn();
if (a) { } // now it doesn't crash
const a = callFn();🙁 Actual behavior
$ yarn tsc test.ts
/project/node_modules/typescript/lib/tsc.js:92656
throw e;
^
RangeError: Maximum call stack size exceeded
at /project/node_modules/typescript/lib/tsc.js:9125:63
at getCombinedFlags (/project/node_modules/typescript/lib/tsc.js:9103:21)
at Object.getCombinedNodeFlags (/project/node_modules/typescript/lib/tsc.js:9125:16)
at getDeclarationNodeFlagsFromSymbol (/project/node_modules/typescript/lib/tsc.js:59070:44)
at checkIdentifier (/project/node_modules/typescript/lib/tsc.js:56890:46)
at checkExpressionWorker (/project/node_modules/typescript/lib/tsc.js:63702:28)
at checkExpression (/project/node_modules/typescript/lib/tsc.js:63657:38)
at checkNonNullExpression (/project/node_modules/typescript/lib/tsc.js:59167:37)
at checkPropertyAccessExpression (/project/node_modules/typescript/lib/tsc.js:59212:85)
at checkExpressionWorker (/project/node_modules/typescript/lib/tsc.js:63734:28)
🙂 Expected behavior
Should report the error Block-scoped variable 'a' used before its declaration.