messageformat/lib/resolve/resolve-function-ref.js

Intl.MessageFormat / Unicode MessageFormat 2 parser, runtime and polyfill

import { MessageError, MessageResolutionError } from "../errors.js";
import { fallback } from "../functions/fallback.js";
import { BIDI_ISOLATE } from "../message-value.js";
import { MessageFunctionContext } from "./function-context.js";
import { getValueSource, resolveValue } from "./resolve-value.js";
export function resolveFunctionRef(ctx, operand, { name, options }) {
    const fnSource = `:${name}`;
    const source = getValueSource(operand) ?? fnSource;
    try {
        const fnInput = operand ? [resolveValue(ctx, operand)] : [];
        const rf = ctx.functions[name];
        if (!rf) {
            throw new MessageResolutionError('unknown-function', `Unknown function ${fnSource}`, source);
        }
        const msgCtx = new MessageFunctionContext(ctx, source, options);
        const opt = resolveOptions(ctx, options);
        const res = rf(msgCtx, opt, ...fnInput);
        if (res === null ||
            typeof res !== 'object' ||
            typeof res.type !== 'string') {
            throw new MessageResolutionError('bad-function-result', `Function ${fnSource} did not return a MessageValue`, source);
        }
        const override = { source };
        if (msgCtx.dir) {
            override.dir = msgCtx.dir;
            override[BIDI_ISOLATE] = true;
        }
        if (msgCtx.id && typeof res.toParts === 'function') {
            override.toParts = () => {
                const parts = res.toParts();
                for (const part of parts)
                    part.id = msgCtx.id;
                return parts;
            };
        }
        return { ...res, ...override };
    }
    catch (error) {
        ctx.onError(error instanceof MessageError
            ? error
            : new MessageResolutionError('bad-function-result', String(error), source, error));
        return fallback(source);
    }
}
function resolveOptions(ctx, options) {
    const opt = Object.create(null);
    if (options) {
        for (const [name, value] of Object.entries(options)) {
            if (!name.startsWith('u:'))
                opt[name] = resolveValue(ctx, value);
        }
    }
    return opt;
}