Script to find all imports from a module in JS/TS code

find-imports.mjs

#! /usr/bin/env node
// Based on https://github.com/montlebalm/find-js-imports
import { readFileSync } from 'fs';
import { basename } from 'path';
import glob from 'glob';
import { fileURLToPath } from 'url';

// https://gist.github.com/manekinekko/7e58a17bc62a9be47172
const IMPORT_RX = /^import (?:["'\s]*([\w*{}\n, ]+) from\s*)?["'\s]*([.@\w\/_-]+)["'\s]*;?/gm;

function getFileMatches(contents, moduleName) {
    const imports = getImports(contents);
    return imports.find(info => info.name === moduleName);
}

function getImports(contents) {
    const imports = [];
    contents.replace(IMPORT_RX, (match, argString, name) => {
        const args = splitImportedArgs(argString);
        if (!args) return;
        imports.push({name, args});
    });
    return imports;
}

function splitImportedArgs(argString) {
    // This can happen when importing css e.g., import 'style.css'
    if (!argString) return;

    const args = argString
        .replace(/^{\s*/, '')
        .replace(/\s*}$/, '')
        .split(/\s*,\s*/);

    return args.reduce(
        (memo, arg) => {
            const parts = arg.split(/\s+as\s+/);
            const [name, alias] = parts;
            memo[name] = alias || name;
            return memo;
        },
        {}
    );
}

function main() {
    const args = process.argv.slice(2);
    if (args.length !== 2) {
        console.error(`
Two arguments expected: glob search patter and module name.

Example:

${basename(fileURLToPath(import.meta.url))} \'src/**/*.{js,ts,tsx}\' react`
        );
        process.exit(1);
    }
    const [pattern, moduleName] = args;

    const globOptions = {
        ignore: ['**/node_modules/**'],
    };

    glob(pattern, globOptions, (err, paths) => {
        if (err) throw new Error(err);

        const files = paths.reduce(
            (memo, path) => {
                const contents = readFileSync(path, 'utf-8');
                const matches = getFileMatches(contents, moduleName);
                if (matches) memo.push(Object.assign({path}, matches));

                return memo;
            },
            []
        );

        console.log(files);
        console.log(new Set(files.map(x => x.path).sort()));
        console.log(new Set(files.flatMap(x => Object.keys(x.args)).sort()));
    });
}

main();