eslint-plugin-mdx/lib/es2015.js

ESLint Plugin for MDX

import { version } from 'eslint/package.json';
import { isJsxNode, arrayify, DEFAULT_EXTENSIONS, MARKDOWN_EXTENSIONS, last } from 'eslint-mdx';
import esLintNoUnusedExpressions from 'eslint/lib/rules/no-unused-expressions';
import path from 'path';
import vfile from 'vfile';
import { cosmiconfigSync } from 'cosmiconfig';
import remarkMdx from 'remark-mdx';
import remarkParse from 'remark-parse';
import remarkStringify from 'remark-stringify';
import unified from 'unified';

const base = {
    parser: 'eslint-mdx',
    plugins: ['mdx'],
    processor: 'mdx/remark',
};

const codeBlocks = {
    parserOptions: {
        ecmaFeatures: {
            // Adding a "use strict" directive at the top of
            // every code block is tedious and distracting, so
            // opt into strict mode parsing without the
            // directive.
            impliedStrict: true,
        },
    },
    rules: {
        // The Markdown parser automatically trims trailing
        // newlines from code blocks.
        'eol-last': 'off',
        // In code snippets and examples, these rules are often
        // counterproductive to clarity and brevity.
        'no-undef': 'off',
        'no-unused-expressions': 'off',
        'no-unused-vars': 'off',
        'padded-blocks': 'off',
        // Adding a "use strict" directive at the top of every
        // code block is tedious and distracting. The config
        // opts into strict mode parsing without the directive.
        strict: 'off',
        // The processor will not receive a Unicode Byte Order
        // Mark from the Markdown parser.
        'unicode-bom': 'off',
    },
};

const getGlobals = (sources, initialGlobals = {}) => (Array.isArray(sources)
    ? sources
    : Object.keys(sources)).reduce((globals, source) => Object.assign(globals, {
    [source]: false,
}), initialGlobals);

let rebass;
try {
    // eslint-disable-next-line @typescript-eslint/no-require-imports, @typescript-eslint/no-var-requires
    rebass = require('rebass');
}
catch (_a) {
    // `rebass`(or `reflexbox` actually) requires `react` as peerDependency, but not all projects using `mdx` are `React` based, so we fallback to hardcoded `rebass` Components here
    /* istanbul ignore next */
    rebass = ['Box', 'Flex', 'Text', 'Heading', 'Link', 'Button', 'Image', 'Card'];
}
const overrides = Object.assign(Object.assign({}, base), { globals: getGlobals(rebass, {
        React: false,
    }), rules: {
        'lines-between-class-members': 0,
        'react/jsx-no-undef': [
            2,
            {
                allowGlobals: true,
            },
        ],
        'react/react-in-jsx-scope': 0,
    } });

const minorVersion = +version.split('.').slice(0, 2).join('.');
const recommended = Object.assign(Object.assign({}, base), { rules: {
        'mdx/no-jsx-html-comments': 2,
        'mdx/no-unused-expressions': 2,
        'mdx/remark': 1,
        'no-unused-expressions': 0,
    } });
const OVERRIDES_AVAILABLE_VERSION = 6.4;
// overrides in npm pkg is supported after v6.4.0
// istanbul ignore else
if (minorVersion >= OVERRIDES_AVAILABLE_VERSION) {
    const overrides = [
        {
            files: '*.mdx',
            extends: 'plugin:mdx/overrides',
        },
        {
            files: '**/*.{md,mdx}/**',
            extends: 'plugin:mdx/code-blocks',
        },
    ];
    try {
        // eslint-disable-next-line node/no-extraneous-require
        require.resolve('prettier');
        // eslint-disable-next-line node/no-extraneous-require
        require.resolve('eslint-plugin-prettier');
        overrides.push({
            files: '*.md',
            rules: {
                'prettier/prettier': [
                    2,
                    {
                        parser: 'markdown',
                    },
                ],
            },
        });
    }
    catch (_a) { }
    Object.assign(recommended, {
        overrides,
    });
}

/* istanbul ignore file */
const configs = {
    base,
    'code-blocks': codeBlocks,
    codeBlocks,
    overrides,
    recommended,
};

const noJsxHtmlComments = {
    meta: {
        type: 'problem',
        docs: {
            description: 'Forbid invalid html style comments in jsx block',
            category: 'SyntaxError',
            recommended: true,
        },
        messages: {
            jsxHtmlComments: 'html style comments are invalid in jsx: {{ origin }}',
        },
        fixable: 'code',
    },
    create(context) {
        return {
            ExpressionStatement(node) {
                const { JSXElementsWithHTMLComments: invalidNodes, } = context.parserServices;
                if (!isJsxNode(node.expression) ||
                    node.parent.type !== 'Program' ||
                    !invalidNodes ||
                    invalidNodes.length === 0) {
                    return;
                }
                const invalidNode = invalidNodes.shift();
                if (invalidNode.data.inline) {
                    return;
                }
                const comments = invalidNode.data.comments;
                for (const { fixed, loc, origin } of comments) {
                    context.report({
                        messageId: 'jsxHtmlComments',
                        data: {
                            origin,
                        },
                        loc,
                        node,
                        fix(fixer) {
                            return fixer.replaceTextRange([loc.start.offset, loc.end.offset], fixed);
                        },
                    });
                }
            },
        };
    },
};

/// <reference path="../../typings.d.ts" />
const noUnusedExpressions = Object.assign(Object.assign({}, esLintNoUnusedExpressions), { create(context) {
        const esLintRuleListener = esLintNoUnusedExpressions.create(context);
        return {
            ExpressionStatement(node) {
                if (isJsxNode(node.expression) && node.parent.type === 'Program') {
                    return;
                }
                esLintRuleListener.ExpressionStatement(node);
            },
        };
    } });

const requirePkg = (plugin, prefix, filePath) => {
    if (filePath && /^\.\.?([/\\]|$)/.test(plugin)) {
        plugin = path.resolve(path.dirname(filePath), plugin);
    }
    prefix = prefix.endsWith('-') ? prefix : prefix + '-';
    const packages = [
        plugin,
        plugin.startsWith('@')
            ? plugin.replace('/', '/' + prefix)
            : prefix + plugin,
    ];
    let error;
    for (const pkg of packages) {
        try {
            // eslint-disable-next-line @typescript-eslint/no-require-imports, @typescript-eslint/no-var-requires
            return require(pkg);
        }
        catch (err) {
            if (!error) {
                error = err;
            }
        }
    }
    throw error;
};
let searchSync;
const remarkProcessor = unified().use(remarkParse).freeze();
const getRemarkProcessor = (searchFrom, isMdx) => {
    if (!searchSync) {
        searchSync = cosmiconfigSync('remark', {
            packageProp: 'remarkConfig',
        }).search;
    }
    let result;
    try {
        result = searchSync(searchFrom);
    }
    catch (err) {
        // https://github.com/eslint/eslint/issues/11989
        /* istanbul ignore if */
        if (err.code !== 'ENOTDIR' ||
            !/\d+_?\.[a-z]+$/.test(searchFrom)) {
            throw err;
        }
        try {
            result = searchSync(path.dirname(searchFrom));
        }
        catch (_a) {
            /* istanbul ignore next */
            throw err;
        }
    }
    /* istanbul ignore next */
    const { plugins = [], settings } = ((result === null || result === void 0 ? void 0 : result.config) ||
        {});
    try {
        // disable this rule automatically since we already have a parser option `extensions`
        // eslint-disable-next-line node/no-extraneous-require
        plugins.push([require.resolve('remark-lint-file-extension'), false]);
    }
    catch (_b) {
        // just ignore if the package does not exist
    }
    const initProcessor = remarkProcessor().use({ settings }).use(remarkStringify);
    if (isMdx) {
        initProcessor.use(remarkMdx);
    }
    return plugins
        .reduce((processor, pluginWithSettings) => {
        const [plugin, ...pluginSettings] = arrayify(pluginWithSettings);
        return processor.use(
        /* istanbul ignore next */
        typeof plugin === 'string'
            ? requirePkg(plugin, 'remark', result.filepath)
            : plugin, ...pluginSettings);
    }, initProcessor)
        .freeze();
};

const remark$1 = {
    meta: {
        type: 'layout',
        docs: {
            description: 'Linter integration with remark plugins',
            category: 'Stylistic Issues',
            recommended: true,
        },
        fixable: 'code',
    },
    create(context) {
        const filename = context.getFilename();
        const extname = path.extname(filename);
        const sourceCode = context.getSourceCode();
        const options = context.parserOptions;
        const isMdx = DEFAULT_EXTENSIONS.concat(options.extensions || []).includes(extname);
        const isMarkdown = MARKDOWN_EXTENSIONS.concat(options.markdownExtensions || []).includes(extname);
        return {
            // eslint-disable-next-line sonarjs/cognitive-complexity
            Program(node) {
                /* istanbul ignore if */
                if (!isMdx && !isMarkdown) {
                    return;
                }
                const sourceText = sourceCode.getText(node);
                const remarkProcessor = getRemarkProcessor(filename, isMdx);
                const file = vfile({
                    path: filename,
                    contents: sourceText,
                });
                try {
                    remarkProcessor.processSync(file);
                }
                catch (err) {
                    /* istanbul ignore next */
                    if (!file.messages.includes(err)) {
                        file.message(err).fatal = true;
                    }
                }
                for (const { source, reason, ruleId, fatal, location: { start, end }, } of file.messages) {
                    // https://github.com/remarkjs/remark-lint/issues/65#issuecomment-220800231
                    /* istanbul ignore next */
                    const severity = fatal ? 2 : fatal == null ? 0 : 1;
                    /* istanbul ignore if */
                    if (!severity) {
                        // should never happen, just for robustness
                        continue;
                    }
                    const message = {
                        reason,
                        source,
                        ruleId,
                        severity,
                    };
                    context.report({
                        // related to https://github.com/eslint/eslint/issues/14198
                        message: JSON.stringify(message),
                        loc: {
                            // ! eslint ast column is 0-indexed, but unified is 1-indexed
                            start: Object.assign(Object.assign({}, start), { column: start.column - 1 }),
                            end: Object.assign(Object.assign({}, end), { column: end.column - 1 }),
                        },
                        node,
                        fix(fixer) {
                            /* istanbul ignore if */
                            if (start.offset == null) {
                                return null;
                            }
                            const range = [
                                start.offset,
                                /* istanbul ignore next */
                                end.offset == null ? start.offset + 1 : end.offset,
                            ];
                            const partialText = sourceText.slice(...range);
                            const fixed = remarkProcessor.processSync(partialText).toString();
                            return fixer.replaceTextRange(range, 
                            /* istanbul ignore next */
                            partialText.endsWith('\n') ? fixed : fixed.slice(0, -1));
                        },
                    });
                }
            },
        };
    },
};

/* istanbul ignore file */
const rules = {
    'no-jsx-html-comments': noJsxHtmlComments,
    'no-unused-expressions': noUnusedExpressions,
    noJsxHtmlComments,
    noUnusedExpressions,
    remark: remark$1,
};

/**
 * based of @link https://github.com/eslint/eslint-plugin-markdown/blob/main/lib/processor.js
 *
 * @fileoverview Processes Markdown files for consumption by ESLint.
 * @author Brandon Mills
 */
const UNSATISFIABLE_RULES = new Set([
    'eol-last',
    'unicode-bom', // Code blocks will begin in the middle of Markdown files
]);
const SUPPORTS_AUTOFIX = true;
const blocksCache = {};
/**
 * Performs a depth-first traversal of the Markdown AST.
 * @param node A Markdown AST node.
 * @param callbacks A map of node types to callbacks.
 * @param parent The node's parent AST node.
 */
function traverse(node, callbacks, parent) {
    if (callbacks[node.type]) {
        callbacks[node.type](node, parent);
    }
    if (typeof node.children !== 'undefined') {
        const parent = node;
        for (const child of parent.children) {
            traverse(child, callbacks, parent);
        }
    }
}
/**
 * Converts leading HTML comments to JS block comments.
 * @param html The text content of an HTML AST node.
 * @returns JS block comment.
 */
function getComment(html) {
    const commentStart = '<!--';
    const commentEnd = '-->';
    const regex = /^(eslint\b|global\s)/u;
    if (html.slice(0, commentStart.length) !== commentStart ||
        html.slice(-commentEnd.length) !== commentEnd) {
        return '';
    }
    const comment = html.slice(commentStart.length, -commentEnd.length);
    if (!regex.test(comment.trim())) {
        return '';
    }
    return comment;
}
// Before a code block, blockquote characters (`>`) are also considered
// "whitespace".
const leadingWhitespaceRegex = /^[>\s]*/u;
/**
 * Gets the offset for the first column of the node's first line in the
 * original source text.
 * @param node A Markdown code block AST node.
 * @returns The offset for the first column of the node's first line.
 */
function getBeginningOfLineOffset(node) {
    return node.position.start.offset - node.position.start.column + 1;
}
/**
 * Gets the leading text, typically whitespace with possible blockquote chars,
 * used to indent a code block.
 * @param text The text of the file.
 * @param node A Markdown code block AST node.
 * @returns The text from the start of the first line to the opening
 *     fence of the code block.
 */
function getIndentText(text, node) {
    return leadingWhitespaceRegex.exec(text.slice(getBeginningOfLineOffset(node)))[0];
}
/**
 * When applying fixes, the postprocess step needs to know how to map fix ranges
 * from their location in the linted JS to the original offset in the Markdown.
 * Configuration comments and indentation trimming both complicate this process.
 *
 * Configuration comments appear in the linted JS but not in the Markdown code
 * block. Fixes to configuration comments would cause undefined behavior and
 * should be ignored during postprocessing. Fixes to actual code after
 * configuration comments need to be mapped back to the code block after
 * removing any offset due to configuration comments.
 *
 * Fenced code blocks can be indented by up to three spaces at the opening
 * fence. Inside of a list, for example, this indent can be in addition to the
 * indent already required for list item children. Leading whitespace inside
 * indented code blocks is trimmed up to the level of the opening fence and does
 * not appear in the linted code. Further, lines can have less leading
 * whitespace than the opening fence, so not all lines are guaranteed to have
 * the same column offset as the opening fence.
 *
 * The source code of a non-configuration-comment line in the linted JS is a
 * suffix of the corresponding line in the Markdown code block. There are no
 * differences within the line, so the mapping need only provide the offset
 * delta at the beginning of each line.
 * @param text The text of the file.
 * @param node A Markdown code block AST node.
 * @param comments List of configuration comment strings that will be
 *     inserted at the beginning of the code block.
 * @returns A list of offset-based adjustments, where lookups are
 *     done based on the `js` key, which represents the range in the linted JS,
 *     and the `md` key is the offset delta that, when added to the JS range,
 *     returns the corresponding location in the original Markdown source.
 */
function getBlockRangeMap(text, node, comments) {
    /*
     * The parser sets the fenced code block's start offset to wherever content
     * should normally begin (typically the first column of the line, but more
     * inside a list item, for example). The code block's opening fancy may be
     * further indented by up to three characters. If the code block has
     * additional indenting, the opening fence's first backtick may be up to
     * three whitespace characters after the start offset.
     */
    const startOffset = getBeginningOfLineOffset(node);
    /*
     * Extract the Markdown source to determine the leading whitespace for each
     * line.
     */
    const code = text.slice(startOffset, node.position.end.offset);
    const lines = code.split('\n');
    /*
     * The parser trims leading whitespace from each line of code within the
     * fenced code block up to the opening fence's first backtick. The first
     * backtick's column is the AST node's starting column plus any additional
     * indentation.
     */
    const baseIndent = getIndentText(text, node).length;
    /*
     * Track the length of any inserted configuration comments at the beginning
     * of the linted JS and start the JS offset lookup keys at this index.
     */
    const commentLength = comments.reduce((len, comment) => len + comment.length + 1, 0);
    /*
     * In case there are configuration comments, initialize the map so that the
     * first lookup index is always 0. If there are no configuration comments,
     * the lookup index will also be 0, and the lookup should always go to the
     * last range that matches, skipping this initialization entry.
     */
    const rangeMap = [
        {
            js: 0,
            md: 0,
        },
    ];
    // Start the JS offset after any configuration comments.
    let jsOffset = commentLength;
    /*
     * Start the Markdown offset at the beginning of the block's first line of
     * actual code. The first line of the block is always the opening fence, so
     * the code begins on the second line.
     */
    let mdOffset = startOffset + lines[0].length + 1;
    /*
     * For each line, determine how much leading whitespace was trimmed due to
     * indentation. Increase the JS lookup offset by the length of the line
     * post-trimming and the Markdown offset by the total line length.
     */
    for (let i = 0; i + 1 < lines.length; i++) {
        const line = lines[i + 1];
        const leadingWhitespaceLength = leadingWhitespaceRegex.exec(line)[0].length;
        // The parser trims leading whitespace up to the level of the opening
        // fence, so keep any additional indentation beyond that.
        const trimLength = Math.min(baseIndent, leadingWhitespaceLength);
        rangeMap.push({
            js: jsOffset,
            // Advance `trimLength` character from the beginning of the Markdown
            // line to the beginning of the equivalent JS line, then compute the
            // delta.
            md: mdOffset + trimLength - jsOffset,
        });
        // Accumulate the current line in the offsets, and don't forget the
        // newline.
        mdOffset += line.length + 1;
        jsOffset += line.length - trimLength + 1;
    }
    return rangeMap;
}
const LANGUAGES_MAPPER = {
    javascript: 'js',
    javascriptreact: 'jsx',
    typescript: 'ts',
    typescriptreact: 'tsx',
    markdown: 'md',
    mdown: 'md',
    mkdn: 'md',
};
/**
 * get short language
 * @param lang original language
 * @returns short language
 */
function getShortLang(lang) {
    const language = last(lang.split(/\s/u)[0].split('.')).toLowerCase();
    return LANGUAGES_MAPPER[language] || language;
}
/**
 * Extracts lintable JavaScript code blocks from Markdown text.
 * @param text The text of the file.
 * @param filename The filename of the file
 * @returns Source code strings to lint.
 */
function preprocess(text, filename) {
    const ast = remarkProcessor.parse(text);
    const blocks = [];
    blocksCache[filename] = blocks;
    traverse(ast, {
        code(node, parent) {
            const comments = [];
            if (node.lang) {
                let index = parent.children.indexOf(node) - 1;
                let previousNode = parent.children[index];
                while (previousNode && previousNode.type === 'html') {
                    const comment = getComment(previousNode.value);
                    if (!comment) {
                        break;
                    }
                    if (comment.trim() === 'eslint-skip') {
                        return;
                    }
                    comments.unshift(`/*${comment}*/`);
                    index--;
                    previousNode = parent.children[index];
                }
                blocks.push(Object.assign(Object.assign({}, node), { baseIndentText: getIndentText(text, node), comments, rangeMap: getBlockRangeMap(text, node, comments) }));
            }
        },
    });
    return blocks.map((block, index) => ({
        filename: `${index}.${getShortLang(block.lang)}`,
        text: [...block.comments, block.value, ''].join('\n'),
    }));
}
/**
 * Creates a map function that adjusts messages in a code block.
 * @param block A code block.
 * @returns A function that adjusts messages in a code block.
 */
function adjustBlock(block) {
    const leadingCommentLines = block.comments.reduce((count, comment) => count + comment.split('\n').length, 0);
    const blockStart = block.position.start.line;
    /**
     * Adjusts ESLint messages to point to the correct location in the Markdown.
     * @param message A message from ESLint.
     * @returns The same message, but adjusted to the correct location.
     */
    return function adjustMessage(message) {
        const lineInCode = message.line - leadingCommentLines;
        if (lineInCode < 1) {
            return null;
        }
        const out = {
            line: lineInCode + blockStart,
            column: message.column + block.position.indent[lineInCode - 1] - 1,
        };
        /* istanbul ignore else */
        if (Number.isInteger(message.endLine)) {
            out.endLine = message.endLine - leadingCommentLines + blockStart;
        }
        const adjustedFix = {};
        /* istanbul ignore else */
        if (message.fix) {
            adjustedFix.fix = {
                range: message.fix.range.map(range => {
                    // Advance through the block's range map to find the last
                    // matching range by finding the first range too far and
                    // then going back one.
                    let i = 1;
                    while (i < block.rangeMap.length && block.rangeMap[i].js <= range) {
                        i++;
                    }
                    // Apply the mapping delta for this range.
                    return range + block.rangeMap[i - 1].md;
                }),
                text: message.fix.text.replace(/\n/gu, `\n${block.baseIndentText}`),
            };
        }
        return Object.assign(Object.assign(Object.assign({}, message), out), adjustedFix);
    };
}
/**
 * Excludes unsatisfiable rules from the list of messages.
 * @param message A message from the linter.
 * @returns True if the message should be included in output.
 */
function excludeUnsatisfiableRules(message) {
    return message && !UNSATISFIABLE_RULES.has(message.ruleId);
}
/**
 * Transforms generated messages for output.
 * @param messages An array containing one array of messages for each code block returned from `preprocess`.
 * @param filename The filename of the file
 * @returns A flattened array of messages with mapped locations.
 */
function postprocess(messages, filename) {
    const blocks = blocksCache[filename] || [];
    // eslint-disable-next-line unicorn/prefer-spread
    return [].concat(...messages.map((group, i) => {
        const block = blocks[i];
        // non code block message, parsed by `eslint-mdx` for example
        if (!block) {
            return group;
        }
        const adjust = adjustBlock(block);
        return group.map(adjust).filter(excludeUnsatisfiableRules);
    }));
}
const markdown = {
    preprocess,
    postprocess,
    supportsAutofix: SUPPORTS_AUTOFIX,
};

/**
 * based on @link https://github.com/sveltejs/eslint-plugin-svelte3/blob/master/src/processor_options.js
 */
const processorOptions = {};
// find Linter instance
const linterPath = Object.keys(require.cache).find(path => /([/\\])eslint\1lib(?:\1linter){2}\.js$/.test(path));
/* istanbul ignore if */
if (!linterPath) {
    throw new Error('Could not find ESLint Linter in require cache');
}
// eslint-disable-next-line @typescript-eslint/consistent-type-imports, @typescript-eslint/no-require-imports, @typescript-eslint/no-var-requires
const ESLinter = require(linterPath).Linter;
// patch Linter#verify
// eslint-disable-next-line @typescript-eslint/unbound-method
const { verify } = ESLinter.prototype;
ESLinter.prototype.verify = function (code, config, options) {
    // fetch settings
    const settings = (config &&
        (typeof config.extractConfig === 'function'
            ? config.extractConfig(
            /* istanbul ignore next */
            typeof options === 'undefined' || typeof options === 'string'
                ? options
                : options.filename)
            : config).settings) ||
        {};
    processorOptions.lintCodeBlocks = settings['mdx/code-blocks'] === true;
    // call original Linter#verify
    return verify.call(this, code, config, options);
};

const remark = {
    supportsAutofix: true,
    preprocess(text, filename) {
        if (!processorOptions.lintCodeBlocks) {
            return [text];
        }
        return [...markdown.preprocess(text, filename), text];
    },
    postprocess(lintMessages, filename) {
        return markdown.postprocess(lintMessages, filename).map(lintMessage => {
            const { message, ruleId: eslintRuleId, severity: eslintSeverity, } = lintMessage;
            if (eslintRuleId !== 'mdx/remark') {
                return lintMessage;
            }
            const { source, ruleId, reason, severity } = JSON.parse(message);
            return Object.assign(Object.assign({}, lintMessage), { ruleId: `${source}-${ruleId}`, message: reason, severity: Math.max(eslintSeverity, severity) });
        });
    },
};

const processors = {
    markdown,
    remark,
};

export { base, codeBlocks, configs, getGlobals, getRemarkProcessor, noJsxHtmlComments, noUnusedExpressions, overrides, processorOptions, processors, recommended, remark$1 as remark, remarkProcessor, requirePkg, rules };