Basic setup

babel-native-config.js

@@ -0,0 +1,4 @@
+module.exports = {
+  presets: ["module:metro-react-native-babel-preset"],
+  plugins: ["@babel/plugin-proposal-export-namespace-from"]
+};

jest-native-config.js

@@ -0,0 +1,11 @@
+module.exports = {
+  moduleFileExtensions: ["ts", "tsx", "js", "jsx", "json", "node"],
+  testMatch: ["**/jest/**/?(*.)+(spec|test).[jt]s?(x)"],
+  transform: {
+    "^.+\\.(js|jsx)$": [
+      "babel-jest",
+      { configFile: "./babel-native-config.js" }
+    ]
+  },
+  setupFiles: ["./jest-native-setup.js"]
+};

jest-native-setup.js

@@ -0,0 +1 @@
+jest.mock("react-native", () => ({}));

package-scripts.js

@@ -17,6 +17,10 @@ module.exports = {
       watch: "karma start --auto-watch ./config/karma/karma.conf.js",
       default: "karma start ./config/karma/karma.conf.js"
     },
+    jest: {
+      native: "jest --config=jest-native-config.js",
+      default: "jest --config=jest-native-config.js"
+    },
     test: {
       cov: npsUtils.series.nps("build-package-libs", "karma.cov"),
       dev: "karma start ./config/karma/karma.conf.dev.js",

package.json

@@ -122,7 +122,10 @@
     "webpack": "^5.0.0",
     "webpack-cli": "^4.7.2",
     "webpack-dev-server": "^3.11.2",
-    "webpack-stats-plugin": "^0.1.1"
+    "webpack-stats-plugin": "^0.1.1",
+    "jest": "27.3.1",
+    "metro-react-native-babel-preset": "0.66.2",
+    "@babel/plugin-proposal-export-namespace-from": "7.16.0"
   },
   "sideEffects": false,
   "dependencies": {

test/jest/native-helpers.test.js

@@ -0,0 +1,88 @@
+import NativeHelpers from "../../packages/victory-native/src/helpers/native-helpers";
+
+describe("getStyle", () => {
+  it("should return undefined if not called with any arguments", () => {
+    expect(NativeHelpers.getStyle()).toEqual(undefined);
+  });
+
+  it("removes all unsupported props and leaves others, including stroke props", () => {
+    expect(
+      NativeHelpers.getStyle({
+        fill: "black",
+        stroke: "grey",
+        pointerEvents: "auto",
+        x: 0,
+        y: 0,
+        _x: 0,
+        _y: 0,
+        userSelect: "none",
+        strokeWidth: 1,
+        strokeOpacity: 1,
+        strokeDasharray: 1,
+        strokeDashoffset: 1,
+        strokeLinecap: 1,
+        strokeLinejoin: 1
+      })
+    ).toEqual({
+      fill: "black",
+      stroke: "grey",
+      strokeWidth: 1,
+      strokeOpacity: 1,
+      strokeDasharray: 1,
+      strokeDashoffset: 1,
+      strokeLinecap: 1,
+      strokeLinejoin: 1
+    });
+  });
+
+  it("removes all unsupported and stroke props when stroke is transparent", () => {
+    expect(
+      NativeHelpers.getStyle({
+        stroke: "transparent",
+        fill: "black",
+        pointerEvents: "auto",
+        x: 0,
+        y: 0,
+        _x: 0,
+        _y: 0,
+        userSelect: "none",
+        strokeWidth: 1,
+        strokeOpacity: 1,
+        strokeDasharray: 1,
+        strokeDashoffset: 1,
+        strokeLinecap: 1,
+        strokeLinejoin: 1
+      })
+    ).toEqual({ fill: "black" });
+  });
+
+  it("removes all unsupported and stroke props when stroke is 'none'", () => {
+    expect(
+      NativeHelpers.getStyle({
+        stroke: "none",
+        fill: "black",
+        pointerEvents: "auto",
+        x: 0,
+        y: 0,
+        _x: 0,
+        _y: 0,
+        userSelect: "none",
+        strokeWidth: 1,
+        strokeOpacity: 1,
+        strokeDasharray: 1,
+        strokeDashoffset: 1,
+        strokeLinecap: 1,
+        strokeLinejoin: 1
+      })
+    ).toEqual({ fill: "black" });
+  });
+
+  it("removes extra properties if given", () => {
+    expect(
+      NativeHelpers.getStyle({ width: 100, height: 100, depth: 100 }, [
+        "width",
+        "depth"
+      ])
+    ).toEqual({ height: 100 });
+  });
+});