typedoc/dist/lib/converter/factories/index-signature.js

Create api documentation for TypeScript projects.

import assert from "assert";
import { DeclarationReflection, ParameterReflection, ReflectionFlag, ReflectionKind, SignatureReflection, UnionType, } from "../../models/index.js";
import { ConverterEvents } from "../converter-events.js";
export function convertIndexSignatures(context, type) {
    assert(context.scope instanceof DeclarationReflection);
    // Each declaration should have one SignatureReflection
    // If we don't have a declaration, the index signature was inferred by TS
    // and we should make a separate SignatureReflection for each index signature.
    const seenByDeclaration = new Map();
    const createdSignatures = [];
    for (const indexInfo of context.checker.getIndexInfosOfType(type)) {
        // Check if we've already created an index signature for this type
        if (indexInfo.declaration &&
            seenByDeclaration.has(indexInfo.declaration)) {
            const createdSig = seenByDeclaration.get(indexInfo.declaration);
            if (createdSig.parameters[0].type?.type !== "union") {
                createdSig.parameters[0].type = new UnionType([
                    createdSig.parameters[0].type,
                ]);
            }
            createdSig.parameters[0].type.types.push(context.converter.convertType(context.withScope(createdSig), indexInfo.keyType));
            // No need to update the return type as it will be the same for all members.
            continue;
        }
        // Otherwise create a new one
        const index = new SignatureReflection("__index", ReflectionKind.IndexSignature, context.scope);
        const ic = context.withScope(index);
        if (indexInfo.isReadonly) {
            index.setFlag(ReflectionFlag.Readonly);
        }
        createdSignatures.push([indexInfo.declaration, index]);
        if (indexInfo.declaration) {
            seenByDeclaration.set(indexInfo.declaration, index);
            index.comment = context.getNodeComment(indexInfo.declaration, 
            /* moduleComment */ false);
        }
        index.parameters = [
            new ParameterReflection(indexInfo.declaration?.parameters[0].name.getText() ?? "key", ReflectionKind.Parameter, index),
        ];
        index.parameters[0].type = context.converter.convertType(ic.withScope(index.parameters[0]), indexInfo.keyType);
        index.type = context.converter.convertType(ic, indexInfo.type);
        context.registerReflection(index, indexInfo.declaration?.symbol);
        context.scope.indexSignatures ||= [];
        context.scope.indexSignatures.push(index);
    }
    // Now that we've created everything, trigger events for them.
    for (const [declaration, index] of createdSignatures) {
        context.converter.trigger(ConverterEvents.CREATE_SIGNATURE, context, index, declaration);
    }
}