fx_cast/extension/bin/lib/copyFilesPlugin.js

// @ts-check
"use strict";

import path from "path";
import fs from "fs";

// eslint-disable-next-line no-unused-vars
import esbuild from "esbuild";

/**
 * Walks file tree from a given root path.
 * @param {string} rootPath
 */
function* walk(rootPath) {
    const pathsToWalk = [rootPath];
    while (pathsToWalk.length > 0) {
        const currentPath = /** @type {string} */ (pathsToWalk.pop());
        if (fs.statSync(currentPath).isFile()) {
            yield currentPath;
        } else {
            for (const child of fs.readdirSync(currentPath)) {
                pathsToWalk.push(path.join(currentPath, child));
            }
        }
    }
}

/**
 * @typedef {object} CopyFilesPluginOpts
 * @prop {string} src Source path
 * @prop {string} dest Destination path
 * @prop {RegExp=} excludePattern Exclude path pattern
 */
/**
 * Plugin that copies files from specified source to destination after
 * each build.
 *
 * @type {(opts: CopyFilesPluginOpts) => esbuild.Plugin}
 */
export default opts => {
    if (!fs.existsSync(opts.src)) {
        throw new Error("copyFilesPlugin: src path not found!");
    }

    const matchingPaths = [...walk(opts.src)].filter(
        path => !opts.excludePattern?.test(path)
    );

    return {
        name: "copy-files",
        setup(build) {
            build.onEnd(() => {
                // Copy any source files that changed
                for (const srcPath of matchingPaths) {
                    const destPath = path.resolve(
                        opts.dest,
                        path.relative(opts.src, srcPath)
                    );

                    // Ignore if source file is missing
                    if (!fs.existsSync(srcPath)) {
                        if (fs.existsSync(destPath)) {
                            fs.rmSync(destPath);
                        }
                        continue;
                    }

                    // Ensure containing destination directory exists
                    const dirName = path.dirname(destPath);
                    if (!fs.existsSync(dirName)) {
                        fs.mkdirSync(dirName, { recursive: true });
                    }

                    // Check if files match
                    if (fs.existsSync(destPath)) {
                        const srcContent = fs.readFileSync(srcPath);
                        const destContent = fs.readFileSync(destPath);

                        if (srcContent.equals(destContent)) {
                            continue;
                        }
                    }

                    fs.copyFileSync(srcPath, destPath);
                }
            });
        }
    };
};