Crash when trying to merge global augmentation

[timocov]

TypeScript Version: 3.0.0-dev.20180703

Search Terms: Global augmentation

Code

1. mkdir src && echo "import * as React from 'react';console.log(React);" > src/index.ts
2. mkdir tests && echo "import * as React from 'react';console.log(React);" > tests/index.ts
3. npm init -y && npm install --save-dev typescript@next @types/react
4. cd tests && npm init -y && npm install --save-dev @types/react && cd ../
5. ./node_modules/.bin/tsc --init
6. ./node_modules/.bin/tsc --noEmit

Expected behavior:

Compiled without errors

Actual behavior:

Error: Debug Failure. False expression.
    at mergeSymbol (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:24252:26)
    at E:\git\ts-bug\node_modules\typescript\lib\tsc.js:24344:49
    at Map.forEach (<anonymous>)
    at mergeSymbolTable (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:24343:20)
    at mergeModuleAugmentation (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:24354:17)
    at initializeTypeChecker (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:45114:25)
    at Object.createTypeChecker (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:24102:9)
    at getDiagnosticsProducingTypeChecker (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:66941:93)
    at Object.getGlobalDiagnostics (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:67286:53)
    at Object.emitFilesAndReportErrors (E:\git\ts-bug\node_modules\typescript\lib\tsc.js:69563:46)

[RyanCavanaugh]

@sandersn probably a better repro for #25339

[timocov]

Probably it can be useful. I guess that the reason of this is in initializeTypeChecker function - it walks through all source files and pushes augmentation to an array (via (augmentations || (augmentations = [])).push(file.moduleAugmentations);), but here we can have source file with redirectInfo, and it is possible that we should skip it in the loop (but I am not sure).

[sandersn]

Thanks @timocov for the excellent repro -- all I had to do was make it work in our test harness. Your fix was exactly right too.