build: Drop ESLint from esbuild

Similar to what commit c9ac6736b3 did for stylelint, move
ESLint to static code checks as well. It already runs from there (and
actually correctly since the previous commit).

HACKING.md

@@ -94,9 +94,6 @@ pkg/lib/), you can also build all pages:
 
     ./build.js -w
 
-Note that this enables eslint by default -- if you want to disable it, run it
-with `-e`/`--no-eslint`.
-
 Reload cockpit in your browser after page is built. Press `Ctrl`-`C` to
 stop watch mode once you are done with changing the code.
 
@@ -232,7 +229,7 @@ The tests require at least `pytest` 7.0.0 or higher to run.
 Cockpit uses [ESLint](https://eslint.org/) to automatically check JavaScript
 code style in `.js` and `.jsx` files.
 
-The linter is executed on every build.
+The linter is executed as part of `test/static-code`.
 
 For developer convenience, the ESLint can be started explicitly by:
 

build.js

@@ -50,7 +50,6 @@ const qunitOptions = {
 const parser = (await import('argparse')).default.ArgumentParser();
 parser.add_argument('-r', '--rsync', { help: "rsync bundles to ssh target after build", metavar: "HOST" });
 parser.add_argument('-w', '--watch', { action: 'store_true', help: "Enable watch mode" });
-parser.add_argument('-e', '--no-eslint', { action: 'store_true', help: "Disable eslint linting", default: production });
 parser.add_argument('onlydir', { nargs: '?', help: "The pkg/<DIRECTORY> to build (eg. base1, shell, ...)", metavar: "DIRECTORY" });
 const args = parser.parse_args();
 
@@ -111,7 +110,6 @@ async function build() {
     const cockpitPoEsbuildPlugin = (await import('./pkg/lib/cockpit-po-plugin.js')).cockpitPoEsbuildPlugin;
     const cockpitRsyncEsbuildPlugin = (await import('./pkg/lib/cockpit-rsync-plugin.js')).cockpitRsyncEsbuildPlugin;
     const cockpitTestHtmlPlugin = (await import('./pkg/lib/esbuild-test-html-plugin.js')).cockpitTestHtmlPlugin;
-    const eslintPlugin = (await import('./pkg/lib/esbuild-eslint-plugin.js')).eslintPlugin;
 
     const esbuildStylesPlugins = (await import('./pkg/lib/esbuild-common.js')).esbuildStylesPlugins;
 
@@ -124,7 +122,6 @@ async function build() {
     ];
 
     const pkgPlugins = [
-        ...args.no_eslint ? [] : [eslintPlugin({ filter: /pkg\/.*\.(jsx?|js?)$/ })],
         cockpitJSResolvePlugin,
         ...esbuildStylesPlugins
     ];
@@ -181,7 +178,6 @@ async function build() {
             ...qunitOptions,
             entryPoints: testEntryPoints,
             plugins: [
-                ...args.no_eslint ? [] : [eslintPlugin({ filter: /pkg\/.*\.(jsx?|js?)$/ })],
                 cockpitTestHtmlPlugin({ testFiles: tests }),
             ],
         });
@@ -200,7 +196,6 @@ async function build() {
             ...qunitOptions,
             entryPoints: testEntryPoints,
             plugins: [
-                ...args.no_eslint ? [] : [eslintPlugin({ filter: /pkg\/.*\.(jsx?|js?)$/ })],
                 cockpitTestHtmlPlugin({ testFiles: tests }),
             ],
         });

pkg/lib/esbuild-eslint-plugin.js

@@ -1,32 +0,0 @@
-// Replace with plugin from npmjs once they become good enough
-// Candidate 1: requires https://github.com/to-codando/esbuild-plugin-linter/issues/1 and https://github.com/to-codando/esbuild-plugin-linter/issues/3 to get fixed
-// Candidate 2: requires https://github.com/robinloeffel/esbuild-plugin-eslint/issues/4 and https://github.com/robinloeffel/esbuild-plugin-eslint/issues/5 to get fixed
-
-import { ESLint } from 'eslint';
-
-const NAME = 'eslintPlugin';
-
-export const eslintPlugin = ({ filter = /src\/.*\.(jsx?|js?)$/ } = {}) => ({
-    name: NAME,
-    setup(build) {
-        const filesToLint = [];
-        const eslint = new ESLint();
-
-        build.onLoad({ filter }, ({ path }) => {
-            filesToLint.push(path);
-        });
-
-        build.onEnd(async () => {
-            const result = await eslint.lintFiles(filesToLint);
-            const formatter = await eslint.loadFormatter('stylish');
-            const output = formatter.format(result);
-            if (output.length > 0) {
-                console.log(output); // eslint-disable no-console
-                return {
-                    errors: [{ pluginName: NAME, text: 'ESLint errors found' }]
-                };
-            }
-            return null;
-        });
-    },
-});