Add API docs for src-radio

src/@types/storybook-emotion-10-fixes.ts

@@ -13,9 +13,10 @@ export type Parameters = {
 	[key: string]: any;
 };
 
-export type Story = {
-	(arg0: any): JSX.Element;
+export type Story<T = Args> = {
+	(arg0: Args & T): JSX.Element;
 	args?: Args;
 	parameters?: Parameters;
+	argTypes?: Args;
 	storyName?: string;
 };

src/core/components/radio/README.md

@@ -10,101 +10,13 @@ $ yarn add @guardian/src-radio
 
 ## Use
 
-```js
-import { RadioGroup, Radio } from '@guardian/src-radio';
+### API
 
-const Form = () => {
-    const [selected, setSelected] = useState(null);
+See [storybook](https://guardian.github.io/source/?path=/docs/source-src-radio-radio--demo)
 
-    return (
-        <form>
-            <RadioGroup
-                name="consent"
-                orientation="vertical"
-                label="Do you accept the terms and conditions?"
-                supporting="The full terms are available on our website"
-            >
-                <Radio
-                    value="no"
-                    label="No"
-                    supporting="I do not accept the terms"
-                    checked={selected === 'no'}
-                    onChange={setSelected('no')}
-                />
-                <Radio
-                    value="yes"
-                    label="Yes"
-                    supporting="I accept the terms"
-                    checked={selected === 'yes'}
-                    onChange={setSelected('yes')}
-                />,
-            </RadioGroup>
-        </form>
-    );
-};
-```
-
-## `RadioGroup` Props
-
-### `name`
-
-**`string`**
-
-Gets passed as the name attribute for each radio button
-
-### `label`
-
-**`string`**
-
-Appears as a legend at the top of the radio group
-
-### `hideLabel`
-
-**`boolean`** _= "false"_
-
-Visually hides the label.
-
-### `supporting`
-
-**`string | JSX.Element` **
-
-Additional text or component that appears below the label
-
-### `orientation`
-
-**`"vertical" | "horizontal"`** _= "vertical"_
-
-The direction in which radio buttons are stacked
-
-### `error`
-
-**`string`**
-
-If passed, error styling should applies to this radio group. The string appears as an inline error message.
-
-## `Radio` Props
-
-### `label`
-
-**`ReactNode`**
-
-Appears to the right of the radio button. If a visible label is undesirable (e.g. for layout reasons) use `aria-label` instead.
-
-If label is omitted, supporting text will not appear either.
-
-### `supporting`
-
-**`ReactNode`**
-
-Additional text or a component that appears below the label
-
-### `checked`
-
-**`boolean`**
-
-Whether radio button is checked. This is necessary when using the [controlled approach](https://reactjs.org/docs/forms.html#controlled-components) to form state management.
+### How to use
 
-**Note:** if you pass the `checked` prop, you **must** also pass an `onChange` handler, or the field will be rendered as read-only.
+For context and visual guides relating to usage see the [Source Design System website](https://theguardian.design/2a1e5182b/p/2891dd-radio-button/b/46940d).
 
 ## Supported themes
 

src/core/components/radio/Radio.stories.tsx

@@ -0,0 +1,124 @@
+import React from 'react';
+import { Radio } from './Radio';
+import type { RadioProps } from './Radio';
+import { radioBrand } from './index';
+import { ThemeProvider } from '@emotion/react';
+import type { Story } from '../../../@types/storybook-emotion-10-fixes';
+import { asPlayground, asChromaticStory } from '../../../lib/story-intents';
+
+// These types are the right types, but don't work with Storybook v6 which uses Emotion v10
+// import type { Args, Story } from '@storybook/react';
+
+export default {
+	title: 'Source/src-radio/Radio',
+	component: Radio,
+	argTypes: {
+		label: {
+			control: {
+				type: 'text',
+			},
+		},
+		supporting: {
+			control: {
+				type: 'text',
+			},
+		},
+		cssOverrides: {
+			control: null,
+		},
+	},
+	args: {
+		label: 'Red',
+		value: 'red',
+		supporting: '',
+		checked: true,
+	},
+};
+
+const Template: Story = (args: RadioProps) => <Radio {...args} />;
+
+// *****************************************************************************
+
+export const Playground = Template.bind({});
+asPlayground(Playground);
+
+// *****************************************************************************
+
+export const DefaultLightTheme = Template.bind({});
+asChromaticStory(DefaultLightTheme);
+
+// *****************************************************************************
+
+export const DefaultBrandTheme = (args: RadioProps) => (
+	<ThemeProvider theme={radioBrand}>
+		<Template {...args} />
+	</ThemeProvider>
+);
+DefaultBrandTheme.parameters = {
+	backgrounds: {
+		default: 'brandBackground.primary',
+	},
+};
+asChromaticStory(DefaultBrandTheme);
+
+// *****************************************************************************
+
+export const SupportingTextLightTheme = Template.bind({});
+SupportingTextLightTheme.args = {
+	supporting: '#ff0000',
+};
+asChromaticStory(SupportingTextLightTheme);
+
+// *****************************************************************************
+
+export const SupportingTextBrandTheme: Story = (args: RadioProps) => (
+	<ThemeProvider theme={radioBrand}>
+		<Template {...args} />
+	</ThemeProvider>
+);
+SupportingTextBrandTheme.parameters = {
+	backgrounds: {
+		default: 'brandBackground.primary',
+	},
+};
+SupportingTextBrandTheme.args = {
+	supporting: '#ff0000',
+};
+asChromaticStory(SupportingTextBrandTheme);
+
+// *****************************************************************************
+
+export const SupportingTextOnlyLightTheme = Template.bind({});
+SupportingTextOnlyLightTheme.args = {
+	supporting: '#ff0000',
+	label: null,
+};
+asChromaticStory(SupportingTextOnlyLightTheme);
+
+// *****************************************************************************
+
+export const SupportingTextOnlyBrandTheme = (args: RadioProps) => (
+	<ThemeProvider theme={radioBrand}>
+		<Template {...args} />
+	</ThemeProvider>
+);
+SupportingTextOnlyBrandTheme.story = {
+	parameters: {
+		backgrounds: {
+			default: 'brandBackground.primary',
+		},
+	},
+};
+SupportingTextOnlyBrandTheme.args = {
+	supporting: '#ff0000',
+	label: null,
+};
+asChromaticStory(SupportingTextOnlyBrandTheme);
+
+// *****************************************************************************
+
+export const UnlabelledLightTheme = Template.bind({});
+UnlabelledLightTheme.args = {
+	label: undefined,
+};
+asChromaticStory(UnlabelledLightTheme);

src/core/components/radio/Radio.tsx

@@ -0,0 +1,132 @@
+import React, { ReactNode, InputHTMLAttributes } from 'react';
+import {
+	label,
+	labelWithSupportingText,
+	radio,
+	labelText,
+	labelTextWithSupportingText,
+	supportingText,
+} from './styles';
+import { Props } from '@guardian/src-helpers';
+
+const LabelText = ({
+	hasSupportingText,
+	children,
+}: {
+	hasSupportingText?: boolean;
+	children: ReactNode;
+}) => {
+	return (
+		<div
+			css={(theme) => [
+				hasSupportingText ? labelTextWithSupportingText : '',
+				labelText(theme.radio && theme),
+			]}
+			className="src-radio-label-text"
+		>
+			{children}
+		</div>
+	);
+};
+
+const SupportingText = ({ children }: { children: ReactNode }) => {
+	return (
+		<div css={(theme) => supportingText(theme.radio && theme)}>
+			{children}
+		</div>
+	);
+};
+
+export interface RadioProps
+	extends InputHTMLAttributes<HTMLInputElement>,
+		Props {
+	/**
+	 * Whether radio button is checked. This is necessary when using the
+	 * [controlled approach](https://reactjs.org/docs/forms.html#controlled-components)
+	 * (recommended) to form state management.
+	 *
+	 * _Note: if you pass the `checked` prop, you MUST also pass an `onChange`
+	 * handler, or the field will be rendered as read-only._
+	 */
+	checked?: boolean;
+	/**
+	 * When using the [uncontrolled approach](https://reactjs.org/docs/uncontrolled-components.html),
+	 * use defaultChecked to indicate the initially checked button.
+	 */
+	defaultChecked?: boolean;
+	/**
+	 * Appears to the right of the radio button. If a visible label is
+	 * undesirable (e.g. for layout reasons) use `aria-label` instead.
+	 *
+	 * If label is omitted, supporting text will not appear either.
+	 */
+	label?: string | ReactNode;
+	/**
+	 * Additional text or a component that appears below the label
+	 */
+	supporting?: string | ReactNode;
+}
+
+/**
+ * [Storybook](https://guardian.github.io/source/?path=/docs/source-src-radio-radio--demo) •
+ * [Design System](https://theguardian.design/2a1e5182b/p/2891dd-radio-button/b/46940d) •
+ * [GitHub](https://github.com/guardian/source/tree/main/src/core/components/radio) •
+ * [NPM](https://www.npmjs.com/package/@guardian/src-radio)
+ *
+ * Radio buttons allow users to make a single selection from a set of options.
+ *
+ * The following themes are supported: `default`, `brand`
+ */
+export const Radio = ({
+	label: labelContent,
+	value,
+	supporting,
+	checked,
+	defaultChecked,
+	cssOverrides,
+	...props
+}: RadioProps) => {
+	const isChecked = (): boolean => {
+		if (checked != null) {
+			return checked;
+		}
+
+		return !!defaultChecked;
+	};
+	const radioControl = (
+		<input
+			type="radio"
+			css={(theme) => [radio(theme.radio && theme), cssOverrides]}
+			value={value}
+			aria-checked={isChecked()}
+			defaultChecked={defaultChecked != null ? defaultChecked : undefined}
+			checked={checked != null ? isChecked() : undefined}
+			{...props}
+		/>
+	);
+
+	const labelledRadioControl = (
+		<label
+			css={(theme) => [
+				label(theme.radio && theme),
+				supporting ? labelWithSupportingText : '',
+			]}
+		>
+			{radioControl}
+			{supporting ? (
+				<div>
+					<LabelText hasSupportingText={true}>
+						{labelContent}
+					</LabelText>
+					<SupportingText>{supporting}</SupportingText>
+				</div>
+			) : (
+				<LabelText>{labelContent}</LabelText>
+			)}
+		</label>
+	);
+
+	return (
+		<>{labelContent || supporting ? labelledRadioControl : radioControl}</>
+	);
+};