TSLint error Object is possibly 'undefined' rule doesn't work on test file using VSCode

[pebie]

Hi,

In my app I've split code and tests files in 2 separated folders

- app
     | -- index.ts
- test
     | -- index.test.ts
- tsconfig.json
- tslint.json

tslint.json:

{
    "extends": ["tslint:latest", "tslint-config-prettier"],
    "linterOptions": {
        "exclude": ["**/*.js"]
    },
    "rules": {
        "object-literal-sort-keys": false,
        "ordered-imports": false,
        "member-ordering": false,
        "curly": [true, "ignore-same-line"],
        "interface-over-type-literal": false,
        "no-string-literal": false,
        "no-implicit-dependencies": [true, "dev"],
        "max-classes-per-file": false,
        "one-variable-per-declaration": false,
        "no-duplicate-imports": true,
        "interface-name": false
    }
}

tsconfig.json

{
    "compilerOptions": {
        "incremental": true,
        "outDir": "./build",
        "allowJs": true,
        "target": "es2018",
        "module": "commonjs",
        "lib": ["es2018"],
        "alwaysStrict": true,
        "sourceMap": true,
        "skipLibCheck": true,
        "noUnusedParameters": false,
        "noUnusedLocals": false,
        "strictNullChecks": true,
        "esModuleInterop": true
    },
    "exclude": ["./node_modules", "./app/static"],
    "include": ["./app/**/*"]
}

TSLint version : 5.18 TS version : 3.5.3

app/index.js

type Test = {
    toto?: {
        tata: {
            truc: string | undefined
        }
    }
}
const test: Test = {}
// Got TSLint errors 👍
// Object is possibly 'undefined' (indeed toto may be undefined)
const tata: string = test.toto.tata.truc 
...

tests/index.js

describe('foo', () => {
        it('bar', () => {
            type Test = {
                toto?: {
                    tata: {
                        truc: string | undefined
                    }
                }
            }

            const test: Test = {}
            // No lint error 👎 
            const tata: string = test.toto.tata.truc
            expect(tata)
        })
    })
...

NB:

• Other lint rules works great in both case (test and code)
• When I execute tslint cli command in a terminal there is no error too (so it may not be an issue with VSCode)

My expected behavior is that error shows up in the Problems panel and highlights as well in editor.

EDIT: It seems the issue provide from strictNullChecks props

[pebie]

I think the only workarround is to use a different tsconfig file https://github.com/Microsoft/TypeScript-Sublime-Plugin/issues/605

[mjbvz]

Are you sure the object is possibly undefined error comes from TSLint? That seems like a normal TS error

[mjbvz]

Closing as this error sounds like it comes from TypeScript instead of being TSLint specific