enso/app/ide-desktop/lib/content/esbuild-config.ts

/**
 * Configuration for the esbuild bundler and build/watch commands.
 *
 * The bundler processes each entry point into a single file, each with no external dependencies and
 * minified. This primarily involves resolving all imports, along with some other transformations
 * (like TypeScript compilation).
 *
 * See the bundlers documentation for more information:
 * https://esbuild.github.io/getting-started/#bundling-for-node
 */

import fs from 'node:fs'
import path, { dirname } from 'node:path'
import child_process from 'node:child_process'
import { fileURLToPath } from 'node:url'

import esbuild from 'esbuild'
import plugin_yaml from 'esbuild-plugin-yaml'
import { NodeModulesPolyfillPlugin } from '@esbuild-plugins/node-modules-polyfill'
import { NodeGlobalsPolyfillPlugin } from '@esbuild-plugins/node-globals-polyfill'
import aliasPlugin from 'esbuild-plugin-alias'
// @ts-ignore
import timePlugin from 'esbuild-plugin-time'
// @ts-ignore
import * as copy_plugin from 'enso-copy-plugin'

import { require_env } from '../../utils.js'
import * as BUILD_INFO from '../../build.json' assert { type: 'json' }
import * as esbuildWatchHelper from '../../esbuild-watch.js'

export const thisPath = path.resolve(dirname(fileURLToPath(import.meta.url)))

// =============================
// === Environment variables ===
// =============================

export interface Arguments {
    /** List of files to be copied from WASM artifacts. */
    wasm_artifacts: string
    /** Directory with assets. Its contents are to be copied. */
    assets_path: string
    /** Path where bundled files are output. */
    output_path: string
    /** The main JS bundle to load WASM and JS wasm-pack bundles. */
    ensogl_app_path: string
}

export function argumentsFromEnv(): Arguments {
    const wasm_artifacts = require_env('ENSO_BUILD_GUI_WASM_ARTIFACTS')
    const assets_path = require_env('ENSO_BUILD_GUI_ASSETS')
    const output_path = path.resolve(require_env('ENSO_BUILD_GUI'), 'assets')
    const ensogl_app_path = require_env('ENSO_BUILD_GUI_ENSOGL_APP')
    return { wasm_artifacts, assets_path, output_path, ensogl_app_path }
}

// ===================
// === Git process ===
// ===================

/**
 * Get output of a git command.
 * @param command Command line following the `git` program.
 * @returns Output of the command.
 */
function git(command: string): string {
    // TODO [mwu] Eventually this should be removed, data should be provided by the build script through `BUILD_INFO`.
    //            The bundler configuration should not invoke git, it is not its responsibility.
    return child_process.execSync(`git ${command}`, { encoding: 'utf8' }).trim()
}

// ==============================
// === Files to manually copy ===
// ==============================

/**
 * Static set of files that are always copied to the output directory.
 */
export function always_copied_files(wasm_artifacts: string) {
    return [
        path.resolve(thisPath, 'src', 'index.html'),
        path.resolve(thisPath, 'src', 'run.js'),
        path.resolve(thisPath, 'src', 'style.css'),
        path.resolve(thisPath, 'src', 'docsStyle.css'),
        ...wasm_artifacts.split(path.delimiter),
    ]
}

/**
 * Generator that yields all files that should be copied to the output directory.
 */
export async function* files_to_copy_provider(wasm_artifacts: string, assets_path: string) {
    console.log('Preparing a new generator for files to copy.')
    yield* always_copied_files(wasm_artifacts)
    for (const file of await fs.promises.readdir(assets_path)) {
        yield path.resolve(assets_path, file)
    }
    console.log('Generator for files to copy finished.')
}

// ================
// === Bundling ===
// ================

export function bundlerOptions(args: Arguments): esbuild.BuildOptions {
    const { output_path, ensogl_app_path, wasm_artifacts, assets_path } = args
    return {
        absWorkingDir: thisPath,
        bundle: true,
        entryPoints: [path.resolve(thisPath, 'src', 'index.ts')],
        outdir: output_path,
        outbase: 'src',
        plugins: [
            plugin_yaml.yamlPlugin({}),
            NodeModulesPolyfillPlugin(),
            NodeGlobalsPolyfillPlugin({ buffer: true, process: true }),
            aliasPlugin({ ensogl_app: ensogl_app_path }),
            timePlugin(),
            copy_plugin.create(() => files_to_copy_provider(wasm_artifacts, assets_path)),
        ],
        define: {
            GIT_HASH: JSON.stringify(git('rev-parse HEAD')),
            GIT_STATUS: JSON.stringify(git('status --short --porcelain')),
            BUILD_INFO: JSON.stringify(BUILD_INFO),
        },
        sourcemap: true,
        minify: true,
        metafile: true,
        format: 'esm',
        publicPath: '/assets',
        platform: 'browser',
        incremental: true,
        color: true,
        logOverride: {
            // Happens in ScalaJS-generated parser (scala-parser.js):
            //    6 │   "fileLevelThis": this
            'this-is-undefined-in-esm': 'silent',
            // Happens in ScalaJS-generated parser (scala-parser.js):
            // 1553 │   } else if ((a === (-0))) {
            'equals-negative-zero': 'silent',
            // Happens in Emscripten-generated MSDF (msdfgen_wasm.js):
            //    1 │ ...typeof module!=="undefined"){module["exports"]=Module}process["o...
            'commonjs-variable-in-esm': 'silent',
            // Happens in Emscripten-generated MSDF (msdfgen_wasm.js):
            //    1 │ ...y{table.grow(1)}catch(err){if(!err instanceof RangeError){throw ...
            'suspicious-boolean-not': 'silent',
        },
    }
}

/** The basic, common settings for the bundler, based on the environment variables.
 *
 * Note that they should be further customized as per the needs of the specific workflow (e.g. watch vs. build).
 **/
export function bundlerOptionsFromEnv(): esbuild.BuildOptions {
    return bundlerOptions(argumentsFromEnv())
}

/** ESBuild options for spawning a watcher, that will continuously rebuild the package. */
export function watchOptions(onRebuild?: () => void, inject?: esbuild.BuildOptions['inject']) {
    return esbuildWatchHelper.toWatchOptions(bundlerOptionsFromEnv(), onRebuild, inject)
}

/** ESBuild options for bundling (one-off build) the package.
 *
 * Relies on the environment variables to be set.
 */
export function bundleOptions() {
    const ret = bundlerOptionsFromEnv()
    ret.watch = false
    ret.incremental = false
    return ret
}

/**
 * Bundles the package.
 */
export async function bundle() {
    try {
        return esbuild.build(bundleOptions())
    } catch (error) {
        console.error(error)
        throw error
    }
}

export default { watchOptions, bundle, bundleOptions }