eslint-plugin-formatjs/rules/no-missing-icu-plural-one-placeholders.js

ESLint plugin for formatjs

import { isLiteralElement, isPluralElement, isSelectElement, isTagElement, parse, } from '@formatjs/icu-messageformat-parser';
import MagicString from 'magic-string';
import { getParserServices } from '../context-compat.js';
import { extractMessages, patchMessage } from '../util.js';
export const name = 'no-missing-icu-plural-one-placeholders';
function verifyAst(context, messageNode, ast) {
    const patches = [];
    _verifyAstAndReplace(ast);
    if (patches.length > 0) {
        const patchedMessage = patchMessage(messageNode, ast, content => {
            return patches
                .reduce((magicString, patch) => {
                switch (patch.type) {
                    case 'prependLeft':
                        return magicString.prependLeft(patch.index, patch.content);
                    case 'remove':
                        return magicString.remove(patch.start, patch.end);
                    case 'update':
                        return magicString.update(patch.start, patch.end, patch.content);
                }
            }, new MagicString(content))
                .toString();
        });
        context.report({
            node: messageNode,
            messageId: 'noMissingIcuPluralOnePlaceholders',
            fix: patchedMessage !== null
                ? fixer => fixer.replaceText(messageNode, patchedMessage)
                : null,
        });
    }
    function _verifyAstAndReplace(ast, root = true) {
        for (const el of ast) {
            if (isPluralElement(el) && el.options['one']) {
                _verifyAstAndReplace(el.options['one'].value, false);
            }
            else if (isSelectElement(el)) {
                for (const { value } of Object.values(el.options)) {
                    _verifyAstAndReplace(value, root);
                }
            }
            else if (isTagElement(el)) {
                _verifyAstAndReplace(el.children, root);
            }
            else if (!root && isLiteralElement(el)) {
                const match = el.value.match(/\b1\b/);
                if (match && el.location) {
                    patches.push({
                        type: 'update',
                        start: el.location.start.offset,
                        end: el.location.end.offset,
                        content: el.value.replace(match[0], '#'),
                    });
                }
            }
        }
    }
}
function checkNode(context, node) {
    const msgs = extractMessages(node);
    for (const [{ message: { defaultMessage }, messageNode, },] of msgs) {
        if (!defaultMessage || !messageNode) {
            continue;
        }
        verifyAst(context, messageNode, parse(defaultMessage, { captureLocation: true }));
    }
}
export const rule = {
    meta: {
        type: 'problem',
        docs: {
            description: 'We use `one {# item}` instead of `one {1 item}` in ICU messages as some locales use the `one` formatting for other similar numbers.',
            url: 'https://formatjs.github.io/docs/tooling/linter#no-explicit-icu-plural',
        },
        fixable: 'code',
        messages: {
            noMissingIcuPluralOnePlaceholders: 'Use `one {# item}` instead of `one {1 item}` in ICU messages.',
        },
        schema: [],
    },
    defaultOptions: [],
    create(context) {
        const callExpressionVisitor = (node) => checkNode(context, node);
        const parserServices = getParserServices(context);
        //@ts-expect-error defineTemplateBodyVisitor exists in Vue parser
        if (parserServices?.defineTemplateBodyVisitor) {
            //@ts-expect-error
            return parserServices.defineTemplateBodyVisitor({
                CallExpression: callExpressionVisitor,
            }, {
                CallExpression: callExpressionVisitor,
            });
        }
        return {
            JSXOpeningElement: (node) => checkNode(context, node),
            CallExpression: callExpressionVisitor,
        };
    },
};