* Enable '--strictNullChecks'
* Fix API baselines
* Make sys.getEnvironmentVariable non-nullable
* make properties optional instead of using `| undefined` in thier type
* reportDiagnostics should be required
* Declare firstAccessor as non-nullable
* Make `some` a type guard
* Fix `getEnvironmentVariable` definition in tests
* Pretend transformFlags are always defined
* Fix one more use of sys.getEnvironmentVariable
* `requiredResponse` accepts undefined, remove assertions
* Mark optional properties as optional instead of using `| undefined`
* Mark optional properties as optional instead of using ` | undefined`
* Remove unnecessary null assertions
* Put the bang on the declaration instead of every use
* Make `createMapFromTemplate` require a parameter
* Mark `EmitResult.emittedFiles` and `EmitResult.sourceMaps` as optional
* Plumb through undefined in emitLsit and EmitExpressionList
* `ElementAccessExpression.argumentExpression` can not be `undefined`
* Add overloads for `writeTokenText`
* Make `shouldWriteSeparatingLineTerminator` argument non-nullable
* Make `synthesizedNodeStartsOnNewLine` argument required
* `PropertyAssignment.initializer` cannot be undefined
* Use one `!` at declaration site instead of on every use site
* Capture host in a constant and avoid null assertions
* Remove few more unused assertions
* Update baselines
* Use parameter defaults
* Update baselines
* Fix lint
* Make Symbol#valueDeclaration and Symbol#declarations non-optional to reduce assertions
* Make Node#symbol and Type#symbol non-optional to reduce assertions
* Make `flags` non-nullable to reduce assertions
* Convert some asserts to type guards
* Make `isNonLocalAlias` a type guard
* Add overload for `getSymbolOfNode` for `Declaration`
* Some more `getSymbolOfNode` changes
* Push undefined suppression into `typeToTypeNodeHelper`
* `NodeBuilderContext.tracker` is never `undefined`
* use `Debug.assertDefined`
* Remove unnecessary tag
* Mark `LiteralType.freshType` and `LiteralTupe.regularType` as required
* Call process.stdout._handle.setBlocking(true)
This prevents output from being truncated when the compiler can output
errors to stdout faster than it can receive them. This may slow down
performance for compilations for many errors, but those were already
quite slow.
* Disable tslint no-unnnecessary-type-assertion-2
It is wrong. It *is* necessary.
Make Program.getMissingFilePaths required
Assume getMissingFilePaths always returns a defined value
Make getMissingFilePaths internal
Replace nullable-bool with enum
Update type to reflect possibility of undefined
Use deepEqual to simplify tests
Make condition const
Don't bother cleaning up map before freeing it
Switch from foreach to for-of to simplify debugging
Use a Map, rather than a FileMap, to track open FileWatchers
Fix compilation errors
Introduce and consume arrayToSet
Fix lint warnings about misplaced braces
Delete incorrect comment
Delete from map during iteration
Eliminate unnecessary type annotations
1. Expose missing files from the `Program`.
2. In `tsc --watch` and `tsserver`, add file watchers to missing files.
3. When missing files are created, schedule compilation (tsc) or refresh
the containing projects (tsserver).
