"TypeError: Cannot read property 'isDeclarationFile' of undefined" when using typesVersions

[leonard-thieu]

Test branch leonard-thieu/DefinitelyTyped#18

---

When testing the typesVersions feature for @types/jquery, I get errors like:

The 'expect' rule threw an error in '/home/travis/build/leonard-thieu/DefinitelyTyped/types/jquery/ts3.1/JQueryStatic.d.ts':
TypeError: Cannot read property 'isDeclarationFile' of undefined
    at walk (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/dtslint/bin/rules/expectRule.js:93:20)
    at applyWithFunction.ctx (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/dtslint/bin/rules/expectRule.js:22:62)
    at Rule.AbstractRule.applyWithFunction (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/tslint/lib/language/rule/abstractRule.js:39:9)
    at getFailures (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/dtslint/bin/rules/expectRule.js:22:25)
    at Rule.applyWithProgram (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/dtslint/bin/rules/expectRule.js:24:29)
    at Linter.applyRule (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/tslint/lib/linter.js:194:29)
    at /home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/tslint/lib/linter.js:139:85
    at Object.flatMap (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/tslint/lib/utils.js:151:29)
    at Linter.getAllFailures (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/tslint/lib/linter.js:139:32)
    at Linter.lint (/home/travis/build/leonard-thieu/DefinitelyTyped/node_modules/tslint/lib/linter.js:99:33)

The process I used was:

• Create a package.json with the following contents:

{
    "private": true,
    "types": "index",
    "typesVersions": {
        ">=3.1.0-0": {
            "*": [
                "ts3.1/*"
            ]
        }
    }
}

• Create a ts3.1 directory and copy relevant files into there.
• Remove the header from ts3.1/index.d.ts.
• Change baseUrl and typeRoots in ts3.1/tsconfig.json to ../../.

[leonard-thieu]

Looks like these errors don't fail the build. Not sure if intentional.