chore(test): make tests run again on older browsers

When removing unnecessary dependencies, polyfills like core-js were
removed, as well as webpack which bundled the tests to es5. With this
commit, tests that need specific browser features are skipped if the
browser does not support them and the code is compiled to es5 by
karma-typescript

.github/workflows/steps.yml

@@ -15,7 +15,7 @@ jobs:
 
       - run: npm ci
 
-      - run: npm test
+      - run: npm run test:ci
         env:
           BROWSER_STACK_USERNAME: ${{ secrets.BROWSER_STACK_USERNAME }}
           BROWSER_STACK_ACCESS_KEY: ${{ secrets. BROWSER_STACK_ACCESS_KEY }}

browserstack-karma.js

@@ -90,6 +90,7 @@ module.exports = {
     browser_version: "11.0",
     os: "Windows",
     os_version: "7",
+    es5: true,
   },
   BS_IE_10: {
     base: "BrowserStack",
@@ -97,5 +98,6 @@ module.exports = {
     browser_version: "10.0",
     os: "Windows",
     os_version: "7",
+    es5: true,
   },
 };

karma.conf.js

@@ -1,6 +1,7 @@
 const ci = !!process.env.CI;
 const watch = !!process.env.WATCH;
 const live = !!process.env.LIVE;
+const es5 = !!process.env.ES5;
 
 const ip = "bs-local.com";
 
@@ -9,8 +10,11 @@ const browserstack = require("./browserstack-karma.js");
 // https://www.browserstack.com/open-source (text search "parallels")
 const BROWSERSTACK_OPEN_SOURCE_CONCURRENCY = 5;
 
+const getBrowserstackBrowsers = () =>
+  Object.keys(browserstack).filter((k) => !!browserstack[k].es5 === es5);
+
 const browsers = ci
-  ? Object.keys(browserstack)
+  ? getBrowserstackBrowsers()
   : live
   ? undefined
   : watch
@@ -43,6 +47,12 @@ module.exports = function (config) {
       compilerOptions: {
         ...require("./tsconfig.json").compilerOptions,
         ...require("./test/tsconfig.json").compilerOptions,
+        sourceMap: false,
+        inlineSourceMap: true,
+        target: es5 ? "es5" : "es6",
+      },
+      bundlerOptions: {
+        sourceMap: true,
       },
       include: process.env.FILES_PATTERN.split(",").concat("src/**/*.ts"),
     },

package.json

@@ -33,6 +33,7 @@
     "unit": "cross-env FILES_PATTERN=\"test/unit/*.ts,test/unit/*.tsx\" karma start karma.conf.js",
     "benchmark": "cross-env FILES_PATTERN=\"test-bundles/benchmark/**/*.js\" karma start karma.conf.cjs --concurrency=1",
     "release": "release-it",
+    "test:ci": "npm test && cross-env ES5=true npm run unit",
     "test": "npm run build && npm run lint && npm run unit"
   },
   "devDependencies": {

test/unit/core.ts

@@ -41,15 +41,7 @@ function map(fn: any, list: any[]) {
 
 const inner = prop("innerHTML");
 
-class A extends HTMLParagraphElement {}
-class B extends HTMLParagraphElement {}
-
 describe("snabbdom", function () {
-  before(function () {
-    customElements.define("p-a", A, { extends: "p" });
-    customElements.define("p-b", B, { extends: "p" });
-  });
-
   let elm: any, vnode0: any;
   beforeEach(function () {
     elm = document.createElement("div");
@@ -199,13 +191,11 @@ describe("snabbdom", function () {
     it("handles classes from both selector and property", function () {
       elm = patch(vnode0, h("div", [h("i.has", { class: { classes: true } })]))
         .elm;
-      assert(elm.firstChild.classList.contains("has"));
-      assert(elm.firstChild.classList.contains("classes"));
-    });
-    it("can create custom elements", function () {
-      const vnode1 = h("p", { is: "p-a" });
-      elm = patch(vnode0, vnode1).elm;
-      assert(elm instanceof A);
+      assert(elm.firstChild.classList.contains("has"), "has `has` class");
+      assert(
+        elm.firstChild.classList.contains("classes"),
+        "has `classes` class"
+      );
     });
     it("can create elements with text content", function () {
       elm = patch(vnode0, h("div", ["I am a string"])).elm;
@@ -378,14 +368,52 @@ describe("snabbdom", function () {
       patch(vnode1, vnode2);
       assert.strictEqual((elm as any).a, "foo");
     });
-    it("handles changing is attribute", function () {
-      const vnode1 = h("p", { is: "p-a" });
-      const vnode2 = h("p", { is: "p-b" });
+    describe("custom elements", function () {
+      if ("customElements" in window) {
+        describe("customized built-in element", function () {
+          const isSafari = /^((?!chrome|android).)*safari/i.test(
+            navigator.userAgent
+          );
 
-      elm = patch(vnode0, vnode1).elm;
-      assert(elm instanceof A);
-      elm = patch(vnode1, vnode2).elm;
-      assert(elm instanceof B);
+          if (!isSafari) {
+            class A extends HTMLParagraphElement {}
+            class B extends HTMLParagraphElement {}
+
+            before(function () {
+              if ("customElements" in window) {
+                customElements.define("p-a", A, { extends: "p" });
+                customElements.define("p-b", B, { extends: "p" });
+              }
+            });
+            it("can create custom elements", function () {
+              if ("customElements" in window) {
+                const vnode1 = h("p", { is: "p-a" });
+                elm = patch(vnode0, vnode1).elm;
+                assert(elm instanceof A);
+              } else {
+                this.skip();
+              }
+            });
+            it("handles changing is attribute", function () {
+              const vnode1 = h("p", { is: "p-a" });
+              const vnode2 = h("p", { is: "p-b" });
+
+              elm = patch(vnode0, vnode1).elm;
+              assert(elm instanceof A);
+              elm = patch(vnode1, vnode2).elm;
+              assert(elm instanceof B);
+            });
+          } else {
+            it.skip("safari does not support customized built-in elements", () => {
+              assert(false);
+            });
+          }
+        });
+      } else {
+        it.skip("browser does not support custom elements", () => {
+          assert(false);
+        });
+      }
     });
     describe("using toVNode()", function () {
       it("can remove previous children of the root element", function () {