Adds basic Fantom test for <Button> (#51380)

Summary:
Pull Request resolved: #51380

Changelog: [internal]

Adding more examples of tests for core components with Fantom :)

Differential Revision: D74874581

Author: rubennorte

packages/react-native/Libraries/Components/__tests__/Button-itest.js

@@ -0,0 +1,248 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ * @oncall react_native
+ */
+
+import '@react-native/fantom/src/setUpDefaultReactNativeEnvironment';
+
+import * as Fantom from '@react-native/fantom';
+import nullthrows from 'nullthrows';
+import * as React from 'react';
+import {Button} from 'react-native';
+
+describe('<Button>', () => {
+  describe('props', () => {
+    describe('title', () => {
+      it('sets the text of the button', () => {
+        const root = Fantom.createRoot();
+
+        Fantom.runTask(() => {
+          root.render(<Button title="Hello" />);
+        });
+
+        expect(
+          root
+            .getRenderedOutput({props: ['foregroundColor', 'backgroundColor']})
+            .toJSX(),
+        ).toEqual(
+          // Upper case on Android (also used by Fantom)
+          <rn-view backgroundColor="rgba(33, 150, 243, 255)">
+            <rn-paragraph foregroundColor="rgba(255, 255, 255, 255)">
+              HELLO
+            </rn-paragraph>
+          </rn-view>,
+        );
+      });
+    });
+
+    describe('color', () => {
+      it('sets the background color of the button (non-iOS)', () => {
+        const root = Fantom.createRoot();
+
+        Fantom.runTask(() => {
+          root.render(<Button title="Hello" color="blue" />);
+        });
+
+        expect(
+          root
+            .getRenderedOutput({props: ['foregroundColor', 'backgroundColor']})
+            .toJSX(),
+        ).toEqual(
+          <rn-view backgroundColor="rgba(0, 0, 255, 255)">
+            <rn-paragraph foregroundColor="rgba(255, 255, 255, 255)">
+              HELLO
+            </rn-paragraph>
+          </rn-view>,
+        );
+      });
+    });
+
+    describe('onPress', () => {
+      it('is called when the button is pressed', () => {
+        const root = Fantom.createRoot();
+
+        const onPressCallback = jest.fn();
+
+        Fantom.runTask(() => {
+          root.render(<Button title="Hello" onPress={onPressCallback} />);
+        });
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+
+        // This is necessary because `<Button>` doesn't provide a `<View>` ref
+        // but an instance of `Touchable`.
+        const buttonViewNode = nullthrows(
+          root.document.documentElement.firstElementChild,
+        );
+
+        Fantom.dispatchNativeEvent(buttonViewNode, 'click', {});
+
+        expect(onPressCallback).toHaveBeenCalledTimes(1);
+      });
+    });
+
+    describe('disabled', () => {
+      it('sets different default colors', () => {
+        const root = Fantom.createRoot();
+
+        Fantom.runTask(() => {
+          root.render(<Button title="Hello" disabled={true} />);
+        });
+
+        expect(
+          root
+            .getRenderedOutput({props: ['foregroundColor', 'backgroundColor']})
+            .toJSX(),
+        ).toEqual(
+          <rn-view backgroundColor="rgba(223, 223, 223, 255)">
+            <rn-paragraph foregroundColor="rgba(161, 161, 161, 255)">
+              HELLO
+            </rn-paragraph>
+          </rn-view>,
+        );
+      });
+
+      it('prevents the button onPress callback from being called', () => {
+        const root = Fantom.createRoot();
+
+        const onPressCallback = jest.fn();
+
+        Fantom.runTask(() => {
+          root.render(
+            <Button title="Hello" disabled={true} onPress={onPressCallback} />,
+          );
+        });
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+
+        // This is necessary because `<Button>` doesn't provide a `<View>` ref
+        // but an instance of `Touchable`.
+        const buttonViewNode = nullthrows(
+          root.document.documentElement.firstElementChild,
+        );
+
+        Fantom.dispatchNativeEvent(buttonViewNode, 'click', {});
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+      });
+
+      it('takes precendence over accessibilityState (set to true)', () => {
+        const root = Fantom.createRoot();
+
+        const onPressCallback = jest.fn();
+
+        Fantom.runTask(() => {
+          root.render(
+            <Button
+              title="Hello"
+              disabled={true}
+              accessibilityState={{disabled: false}}
+              onPress={onPressCallback}
+            />,
+          );
+        });
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+
+        // This is necessary because `<Button>` doesn't provide a `<View>` ref
+        // but an instance of `Touchable`.
+        const buttonViewNode = nullthrows(
+          root.document.documentElement.firstElementChild,
+        );
+
+        Fantom.dispatchNativeEvent(buttonViewNode, 'click', {});
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+      });
+
+      it('takes precendence over accessibilityState (set to false)', () => {
+        const root = Fantom.createRoot();
+
+        const onPressCallback = jest.fn();
+
+        Fantom.runTask(() => {
+          root.render(
+            <Button
+              title="Hello"
+              disabled={false}
+              accessibilityState={{disabled: true}}
+              onPress={onPressCallback}
+            />,
+          );
+        });
+
+        expect(
+          root
+            .getRenderedOutput({props: ['foregroundColor', 'backgroundColor']})
+            .toJSX(),
+        ).toEqual(
+          <rn-view backgroundColor="rgba(33, 150, 243, 255)">
+            <rn-paragraph foregroundColor="rgba(255, 255, 255, 255)">
+              HELLO
+            </rn-paragraph>
+          </rn-view>,
+        );
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+
+        // This is necessary because `<Button>` doesn't provide a `<View>` ref
+        // but an instance of `Touchable`.
+        const buttonViewNode = nullthrows(
+          root.document.documentElement.firstElementChild,
+        );
+
+        Fantom.dispatchNativeEvent(buttonViewNode, 'click', {});
+
+        expect(onPressCallback).toHaveBeenCalledTimes(1);
+      });
+    });
+
+    describe('accessibilityState', () => {
+      it('disables the button when disabled property is true and disabled prop is NOT set', () => {
+        const root = Fantom.createRoot();
+
+        const onPressCallback = jest.fn();
+
+        Fantom.runTask(() => {
+          root.render(
+            <Button
+              title="Hello"
+              accessibilityState={{disabled: true}}
+              onPress={onPressCallback}
+            />,
+          );
+        });
+
+        expect(
+          root
+            .getRenderedOutput({props: ['foregroundColor', 'backgroundColor']})
+            .toJSX(),
+        ).toEqual(
+          <rn-view backgroundColor="rgba(223, 223, 223, 255)">
+            <rn-paragraph foregroundColor="rgba(161, 161, 161, 255)">
+              HELLO
+            </rn-paragraph>
+          </rn-view>,
+        );
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+
+        // This is necessary because `<Button>` doesn't provide a `<View>` ref
+        // but an instance of `Touchable`.
+        const buttonViewNode = nullthrows(
+          root.document.documentElement.firstElementChild,
+        );
+
+        Fantom.dispatchNativeEvent(buttonViewNode, 'click', {});
+
+        expect(onPressCallback).toHaveBeenCalledTimes(0);
+      });
+    });
+  });
+});