build: build minified version

Also improve build process while we're here.

.eslintrc.json

@@ -0,0 +1,12 @@
+{
+  "extends": "plugin:prettier/recommended",
+  "parserOptions": {
+    "sourceType": "module",
+    "ecmaVersion": 2018
+  },
+  "env": {
+    "es6": true,
+    "node": true,
+    "browser": true
+  }
+}

package.json

@@ -1,6 +1,6 @@
 {
   "name": "d3-tube-map",
-  "version": "1.2.1",
+  "version": "1.2.2",
   "description": "Draw tube maps in the style of the London Underground",
   "keywords": [
     "d3",
@@ -9,30 +9,34 @@
     "map",
     "visualization"
   ],
-  "homepage": "http://www.pubmap.co.uk/",
+  "homepage": "https://github.com/johnwalley/d3-tube-map/",
   "license": "BSD-3-Clause",
   "author": {
     "name": "John Walley",
     "url": "http://www.walley.org.uk/"
   },
   "main": "dist/d3-tube-map.js",
-  "module": "index.js",
+  "unpkg": "dist/d3-tube.min.js",
+  "jsdelivr": "dist/d3-tube.min.js",
+  "module": "src/index.js",
   "files": [
-    "dist/*.js"
+    "dist/**/*.js",
+    "src/**/*.js"
   ],
   "repository": {
     "type": "git",
     "url": "https://github.com/johnwalley/d3-tube-map.git"
   },
   "scripts": {
-    "pretest": "rm -rf dist && mkdir dist && rollup -c --banner \"$(preamble)\"",
-    "test": "tape 'test/**/*-test.js' && eslint index.js src",
-    "prepublishOnly": "npm run test && uglifyjs -b beautify=false,preamble=\"'$(preamble)'\" dist/d3-tube-map.js -c -m -o dist/d3-tube-map.min.js",
+    "pretest": "rm -rf dist && mkdir dist && rollup -c",
+    "test": "tape 'test/**/*-test.js' && eslint src",
+    "prepublishOnly": "npm run test",
     "postpublish": "zip -j dist/d3-tube-map.zip -- LICENSE README.md dist/d3-tube-map.js dist/d3-tube-map.min.js"
   },
   "dependencies": {
     "d3": "5"
   },
+  "sideEffects": false,
   "devDependencies": {
     "eslint": "6.8.0",
     "eslint-config-prettier": "6.10.0",
@@ -41,6 +45,7 @@
     "package-preamble": "0.1.0",
     "prettier": "1.19.1",
     "rollup": "2.7.6",
+    "rollup-plugin-terser": "5",
     "tape": "5.0.0",
     "uglify-js": "3.8.0"
   }

rollup.config.js

@@ -1,14 +1,39 @@
-const definition = require('./package.json');
-const dependencies = Object.keys(definition.dependencies);
+import { terser } from 'rollup-plugin-terser';
+import * as meta from './package.json';
 
-export default {
-  input: 'index',
+const dependencies = Object.keys(meta.dependencies);
+
+const config = {
+  input: 'src/index.js',
   external: dependencies,
   output: {
     extend: true,
-    file: `dist/${definition.name}.js`,
+    file: `dist/${meta.name}.js`,
     format: 'umd',
     globals: dependencies.reduce((p, v) => ((p[v] = 'd3'), p), {}),
     name: 'd3',
+    banner: `// ${meta.homepage} v${
+      meta.version
+    } Copyright ${new Date().getFullYear()} ${meta.author.name}`,
   },
+  plugins: [],
 };
+
+export default [
+  config,
+  {
+    ...config,
+    output: {
+      ...config.output,
+      file: `dist/${meta.name}.min.js`,
+    },
+    plugins: [
+      ...config.plugins,
+      terser({
+        output: {
+          preamble: config.output.banner,
+        },
+      }),
+    ],
+  },
+];

src/index.js

@@ -0,0 +1 @@
+export { default as tubeMap } from './map';

test/map-test.js

@@ -20,8 +20,7 @@ tape('map(selection) produces the expected result', function(test) {
     fs.readFileSync(path.join(__dirname, 'map.json'), 'utf8')
   );
 
-  d3
-    .select(bodyActual)
+  d3.select(bodyActual)
     .select('div')
     .datum(data)
     .call(d3.tubeMap());