Cannot read property 'expression' of undefined

[vjeux]

There are two tests in the typescript codebase that make typescript-eslint-parser throw:

../TypeScript/tests//cases/conformance/parser/ecmascript5/ErrorRecovery/ExtendsOrImplementsClauses/parserErrorRecovery_ExtendsOrImplementsClause1.ts: TypeError: Cannot read property 'expression' of undefined
    at convert (/Users/despairblue/git/prettier/node_modules/typescript-eslint-parser/lib/ast-converter.js:1580:79)

../TypeScript/tests//cases/conformance/parser/ecmascript5/ErrorRecovery/ExtendsOrImplementsClauses/parserErrorRecovery_ExtendsOrImplementsClause3.ts: TypeError: Cannot read property 'expression' of undefined
    at convert (/Users/despairblue/git/prettier/node_modules/typescript-eslint-parser/lib/ast-converter.js:1580:79)
    at convertChild (/Users/despairblue/git/prettier/node_modules/typescript-eslint-parser/lib/ast-converter.js:501:20)
    at /Users/despairblue/git/prettier/node_modules/typescript-eslint-parser/lib/ast-converter.js:746:46
    at Array.forEach (native)
    at convert (/Users/despairblue/git/prettier/node_modules/typescript-eslint-parser/lib/ast-converter.js:745:33)
    at module.exports (/Users/despairblue/git/prettier/node_modules/typescript-eslint-parser/lib/ast-converter.js:2089:18)
    at Object.parse (/Users/despairblue/git/prettier/node_modules/typescript-eslint-parser/parser.js:239:12)
    at parseWithTypeScript (/Users/despairblue/git/prettier/src/parser.js:58:17)
    at parse (/Users/despairblue/git/prettier/index.js:32:12)
    at format (/Users/despairblue/git/prettier/index.js:80:15)
    at formatWithShebang (/Users/despairblue/git/prettier/index.js:91:12)
    at Object.format (/Users/despairblue/git/prettier/index.js:105:12)

Was found in prettier/prettier#1480

Those are the only two crashes from typescript-eslint-parser of the entire run: https://gist.githubusercontent.com/despairblue/79e090660fbb4093b35ab3b24c617dfb/raw/99e47ad1e34c32ddd91c15315f3c4fb92fa37d65/errors

[soda0289]

Thanks for the report.

Do you have some sample code that can reproduce the problem? I'm having a hard time understanding the output you posted

[vjeux]

Sorry it was confusing, those two files are triggering it:

https://github.com/Microsoft/TypeScript/blob/master/tests/cases/conformance/parser/ecmascript5/ErrorRecovery/ExtendsOrImplementsClauses/parserErrorRecovery_ExtendsOrImplementsClause3.ts
https://github.com/Microsoft/TypeScript/blob/master/tests/cases/conformance/parser/ecmascript5/ErrorRecovery/ExtendsOrImplementsClauses/parserErrorRecovery_ExtendsOrImplementsClause1.ts

[vjeux]

This is the stack trace from this project:

    at convert (typescript-eslint-parser/lib/ast-converter.js:1580:79)
    at convertChild (typescript-eslint-parser/lib/ast-converter.js:501:20)
    at typescript-eslint-parser/lib/ast-converter.js:746:46
    at Array.forEach (native)
    at convert (typescript-eslint-parser/lib/ast-converter.js:745:33)
    at module.exports (typescript-eslint-parser/lib/ast-converter.js:2089:18)
    at Object.parse (typescript-eslint-parser/parser.js:239:12)

[soda0289]

@vjeux Thanks.

I did not know extend could be empty, you would think the typescript parser would complain about this. Will fix this case later today.

[vjeux]

This looks like it's in "ErrorRecovery" directory, so typescript is trying to be lenient around those things.

[vjeux]

The good thing is that this is the only error triggered by this project when running against all the 11k files of the typescript test suite :)

[JamesHenry]

That is fantastic news, thanks again for running those tests!