Compiler API: Expose More from typescript.d.ts

TypeScript Version: 2.9.0-dev.20180426

While Traversing the TypeScript AST of a source file, there have been a number of helpful things I've found by extending ts.* from typescript.d.ts and I would like it if these could be exposed (or not marked /* @internal */).

Search Terms:
typescript.d.ts
Node.locals
Symbol.parent
getContainingFunction
isAssignmentTarget

Code

declare namespace ts {
    interface Node {
        /* @internal */ readonly locals?: SymbolTable; // Locals associated with node (initialized by binding)
    }

    interface Symbol {
        /* @internal */ readonly parent?: Symbol; // Parent symbol
    }

    function getContainingFunction(node: Node): SignatureDeclaration | undefined;

    function isAssignmentTarget(node: Node): boolean;
}

Note:

• Added readonly for Node#locals & Symbol#parent
• For Symbol#parent, the goal is: given the symbol for a method (e.g., methodSymbol for Number#toString) find where that method is defined (e.g., Number)... maybe program.getTypeChecker().getSymbolAtLocation(methodSymbol.valueDeclaration.parent) is what is "supposed" to be used instead?
• For ts.getContainingFunction() it seems more appropriate to have a return type of SignatureDeclaration | undefined instead of SignatureDeclaration

Related Issues:
#15841

Commencez par les déclarations publiques de typescript.d.ts et comparez les membres indiqués Node.locals, Symbol.parent, getContainingFunction et isAssignmentTarget avec leurs implémentations dans le compilateur. Résolvez les questions soulevées concernant l’API et les types de retour, puis vérifiez que les membres prévus sont exposés de manière cohérente aux consommateurs de Compiler API.