replace-in-file/dist/src/helpers/replace.js

A simple utility to quickly replace text in one or more files.

/**
 * Get replacement helper
 */
export function getReplacement(replace, i) {
    if (Array.isArray(replace)) {
        return replace[i] ?? null;
    }
    return replace;
}
/**
 * Escape string to make it safe for use in a regex
 */
export function escapeRegex(string) {
    if (typeof string === 'string') {
        return string.replace(/[.*+?^${}()|[\]\\/]/g, '\\$&');
    }
    return string;
}
/**
 * Helper to make replacements
 */
export function makeReplacements(contents, from, to, file, count) {
    //Turn into array
    if (!Array.isArray(from)) {
        from = [from];
    }
    //Prepare result
    const result = { file, hasChanged: false };
    //Counting? Initialize number of matches
    if (count) {
        result.numMatches = 0;
        result.numReplacements = 0;
    }
    //Make replacements
    const newContents = from.reduce((contents, item, i) => {
        //Call function if given, passing in the filename
        const search = (typeof item === 'function') ? item(file) : item;
        //Get replacement value
        const replacement = getReplacement(to, i);
        if (replacement === null) {
            return contents;
        }
        //Count matches
        if (count) {
            const matches = contents.match(escapeRegex(search));
            if (matches) {
                const replacements = matches.filter(match => match !== replacement);
                result.numMatches += matches.length;
                result.numReplacements += replacements.length;
            }
        }
        //Make replacement, appending the filename if a function is given
        if (typeof replacement === 'function') {
            return contents.replace(search, (...args) => replacement(...args, file));
        }
        return contents.replace(search, replacement);
    }, contents);
    //Check if changed
    result.hasChanged = (newContents !== contents);
    //Return result and new contents
    return [result, newContents];
}
/**
 * Helper to replace in a single file (sync)
 */
export function replaceSync(source, from, to, config) {
    //Extract relevant config and read file contents
    const { getTargetFile, encoding, dry, countMatches, fsSync } = config;
    const contents = fsSync.readFileSync(source, encoding);
    //Replace contents and check if anything changed
    const [result, newContents] = makeReplacements(contents, from, to, source, countMatches);
    //Get target file
    const target = getTargetFile(source);
    //Contents changed and not a dry run? Write to file
    if (result.hasChanged && !dry) {
        fsSync.writeFileSync(target, newContents, encoding);
    }
    //Return result
    return result;
}
/**
 * Helper to replace in a single file (async)
 */
export async function replaceAsync(source, from, to, config) {
    //Extract relevant config and read file contents
    const { getTargetFile, encoding, dry, countMatches, fs } = config;
    const contents = await fs.readFile(source, encoding);
    //Make replacements
    const [result, newContents] = makeReplacements(contents, from, to, source, countMatches);
    //Get target file
    const target = getTargetFile(source);
    //Contents changed and not a dry run? Write to file
    if (result.hasChanged && !dry) {
        await fs.writeFile(target, newContents, encoding);
    }
    //Return result
    return result;
}