Drop legacy browser support (#8009)

* Drop legacy browser support

* Docs

* Use rollup-plugin-istanbul for coverage

* exclude node_modules from coverage

* No cleanup() when doing coverage

.browserslistrc

@@ -1,4 +1,4 @@
-> 0.5%
-last 2 versions
-Firefox ESR
-not dead
+defaults
+not IE 11
+not IE_Mob 11
+maintained node versions

.eslintrc.yml

@@ -7,8 +7,6 @@ env:
   browser: true
   node: true
 
-parser: babel-eslint
-
 parserOptions:
   ecmaVersion: 7
   sourceType: module

babel.config.json

@@ -1,19 +0,0 @@
-{
-  "presets": [
-    [
-		"@babel/preset-env", {
-			"loose": true
-		}
-	]
-  ],
-  "plugins": [
-    "@babel/plugin-transform-object-assign"
-  ],
-  "env": {
-    "test": {
-      "plugins": [
-        "istanbul"
-      ]
-    }
-  }
-}

docs/docs/developers/index.md

@@ -22,13 +22,14 @@ Latest builds are available for testing at:
 
 ## Browser support
 
-Chart.js offers support for the following browsers:
+All modern and up-to-date browsers are supported, including, but not limited to:
 
-- Chrome 50+
-- Firefox 45+
-- Internet Explorer 11
-- Edge 14+
-- Safari 9+
+Chrome
+Edge
+Firefox
+Safari
+
+As of version 3, we have dropped Internet Explorer 11 support.
 
 Browser support for the canvas element is available in all modern & major mobile browsers. [CanIUse](https://caniuse.com/#feat=canvas)
 

karma.conf.js

@@ -1,12 +1,12 @@
 /* eslint-disable import/no-commonjs */
 
 const commonjs = require('@rollup/plugin-commonjs');
+const istanbul = require('rollup-plugin-istanbul');
 const json = require('@rollup/plugin-json');
 const resolve = require('@rollup/plugin-node-resolve').default;
 const builds = require('./rollup.config');
 const yargs = require('yargs');
 
-
 module.exports = function(karma) {
 	const args = yargs
 		.option('verbose', {default: false})
@@ -22,6 +22,14 @@ module.exports = function(karma) {
 	const regex = karma.autoWatch ? /chart\.js$/ : /chart\.min\.js$/;
 	const build = builds.filter(v => v.output.file && v.output.file.match(regex))[0];
 
+	if (args.coverage) {
+		build.plugins = [
+			json(),
+			resolve(),
+			istanbul({exclude: ['node_modules/**/*.js', 'package.json']})
+		];
+	}
+
 	karma.set({
 		frameworks: ['jasmine'],
 		reporters: ['progress', 'kjhtml'],
@@ -101,11 +109,6 @@ module.exports = function(karma) {
 		browserDisconnectTolerance: 3
 	});
 
-	// https://swizec.com/blog/how-to-run-javascript-tests-in-chrome-on-travis/swizec/6647
-	if (process.env.TRAVIS) {
-		karma.customLaunchers.chrome.flags.push('--no-sandbox');
-	}
-
 	if (args.coverage) {
 		karma.reporters.push('coverage');
 		karma.coverageReporter = {

package.json

@@ -44,16 +44,11 @@
     "typedoc": "npx typedoc"
   },
   "devDependencies": {
-    "@babel/core": "^7.12.3",
-    "@babel/plugin-transform-object-assign": "^7.12.1",
-    "@babel/preset-env": "^7.12.1",
     "@kurkle/color": "^0.1.9",
     "@rollup/plugin-commonjs": "^16.0.0",
     "@rollup/plugin-inject": "^4.0.2",
     "@rollup/plugin-json": "^4.1.0",
     "@rollup/plugin-node-resolve": "^10.0.0",
-    "babel-plugin-istanbul": "^6.0.0",
-    "babel-preset-es2015-rollup": "^3.0.0",
     "chartjs-adapter-moment": "^0.1.2",
     "concurrently": "^5.3.0",
     "coveralls": "^3.1.0",
@@ -76,12 +71,10 @@
     "karma-safari-private-launcher": "^1.0.0",
     "moment": "^2.29.1",
     "pixelmatch": "^5.2.1",
-    "promise-polyfill": "^8.2.0",
-    "resize-observer-polyfill": "^1.5.1",
     "rollup": "^2.33.1",
-    "rollup-plugin-babel": "^4.4.0",
     "rollup-plugin-cleanup": "^3.2.1",
     "rollup-plugin-dts": "^1.4.13",
+    "rollup-plugin-istanbul": "^2.0.1",
     "rollup-plugin-terser": "^7.0.2",
     "typedoc": "^0.19.2",
     "typescript": "^4.0.5",

rollup.config.js

@@ -1,10 +1,8 @@
 /* eslint-disable import/no-commonjs */
 /* eslint-env es6 */
 
-const babel = require('rollup-plugin-babel');
 const cleanup = require('rollup-plugin-cleanup');
 const dts = require('rollup-plugin-dts').default;
-const inject = require('@rollup/plugin-inject');
 const json = require('@rollup/plugin-json');
 const resolve = require('@rollup/plugin-node-resolve').default;
 const terser = require('rollup-plugin-terser').terser;
@@ -34,13 +32,8 @@ module.exports = [
 	{
 		input,
 		plugins: [
-			inject({
-				ResizeObserver: 'resize-observer-polyfill',
-				Promise: 'promise-polyfill'
-			}),
 			json(),
 			resolve(),
-			babel(),
 			cleanup({
 				sourcemap: true
 			})
@@ -56,13 +49,8 @@ module.exports = [
 	{
 		input,
 		plugins: [
-			inject({
-				ResizeObserver: 'resize-observer-polyfill',
-				Promise: 'promise-polyfill'
-			}),
 			json(),
 			resolve(),
-			babel(),
 			terser({
 				output: {
 					preamble: banner

src/plugins/plugin.legend.js

@@ -345,10 +345,7 @@ export class Legend extends Element {
 			ctx.lineWidth = lineWidth;
 			ctx.strokeStyle = valueOrDefault(legendItem.strokeStyle, defaultColor);
 
-			if (ctx.setLineDash) {
-				// IE 9 and 10 do not support line dash
-				ctx.setLineDash(valueOrDefault(legendItem.lineDash, []));
-			}
+			ctx.setLineDash(valueOrDefault(legendItem.lineDash, []));
 
 			if (labelOpts && labelOpts.usePointStyle) {
 				// Recalculate x and y for drawPoint() because its expecting