feat(LoadingIndicator)!: introduce 2.0 component (#1963)

- add tests and snapshots
- update API and component documentation
- update token usages

src/components/LoadingIndicator/LoadingIndicator-v2.module.css

@@ -0,0 +1,34 @@
+/*------------------------------------*\
+    # LOADINGINDICATOR
+\*------------------------------------*/
+
+/**
+ * LoadingIndicator
+ */
+.loading-indicator {
+  background-color: transparent;
+  padding: 3px; /* ported from react-loader-spinner */
+  display: flex;
+}
+
+.loading-indicator--invisible {
+  display: none;
+}
+
+/* override for `color` */
+.loading-indicator > svg path {
+  stroke: var(--eds-theme-color-border-utility-informational);
+}
+
+/* override for `secondaryColor` */
+.loading-indicator > svg circle {
+  stroke: var(--eds-theme-color-border-utility-default-low-emphasis);
+  stroke-opacity: 1;
+}
+
+@media screen and (prefers-reduced-motion: reduce) {
+  /* if reducing motion, don't show the moving portion */
+  .loading-indicator > svg path {
+    stroke: none;
+  }
+}

src/components/LoadingIndicator/LoadingIndicator-v2.stories.ts

@@ -0,0 +1,53 @@
+import type { StoryObj, Meta } from '@storybook/react';
+import type React from 'react';
+
+import { LoadingIndicator } from './LoadingIndicator-v2';
+
+export default {
+  title: 'Components/V2/LoadingIndicator',
+  component: LoadingIndicator,
+  parameters: {
+    layout: 'centered',
+    badges: ['intro-1.2', 'current-2.0'],
+  },
+} as Meta<Args>;
+
+type Args = React.ComponentProps<typeof LoadingIndicator>;
+
+export const Default: StoryObj<Args> = {};
+
+export const ExtraSmall: StoryObj<Args> = {
+  args: {
+    size: 'xs',
+  },
+};
+
+export const Small: StoryObj<Args> = {
+  args: {
+    size: 'sm',
+  },
+};
+
+export const Medium: StoryObj<Args> = {
+  args: {
+    size: 'md',
+  },
+};
+
+export const Large: StoryObj<Args> = {
+  args: {
+    size: 'lg',
+  },
+};
+
+export const Invisible: StoryObj<Args> = {
+  args: {
+    isVisible: false,
+  },
+};
+
+export const WithAriaLabel: StoryObj<Args> = {
+  args: {
+    ariaLabel: 'Loading, Please Wait',
+  },
+};

src/components/LoadingIndicator/LoadingIndicator-v2.test.ts

@@ -0,0 +1,6 @@
+import { generateSnapshots } from '@chanzuckerberg/story-utils';
+import * as stories from './LoadingIndicator-v2.stories';
+
+describe('<LoadingIndicator /> (v2)', () => {
+  generateSnapshots(stories);
+});

src/components/LoadingIndicator/LoadingIndicator-v2.tsx

@@ -0,0 +1,124 @@
+import clsx from 'clsx';
+import React from 'react';
+
+import type { Size } from '../../util/variant-types';
+
+import styles from './LoadingIndicator-v2.module.css';
+
+export type LoadingIndicatorProps = {
+  // Component API
+  /**
+   * CSS class names that can be appended to the component.
+   */
+  className?: string;
+  /**
+   * Aria label of the oval. Default is "loading". Will be overridden if ariaLabel is passed in props
+   */
+  ariaLabel?: string;
+  // Design API
+  /**
+   * Layout size of the loader. This affects the overall size and associated
+   * stroke width.
+   */
+  size?: Extract<Size, 'xs' | 'sm' | 'md' | 'lg'>;
+  /**
+   * Whether the oval is visible. Default is true.
+   */
+  isVisible?: boolean;
+};
+
+// Pixel sizes corresponding to EDS size units
+const loaderSize = {
+  xs: 16, // --eds-size-1
+  sm: 24, // --eds-size-2-and-half
+  md: 40, // --eds-size-5
+  lg: 56, // --eds-size-7
+};
+
+// Given a loader size, the stroke widths can change
+const loaderStrokeSize = {
+  xs: 2,
+  sm: 2,
+  md: 3,
+  lg: 4,
+};
+
+// The viewport changes based on adjustments to handle the stroke width
+const loaderViewportSize = {
+  xs: '-20 -20 42 42',
+  sm: '-20 -20 42 42',
+  md: '-20.5 -20.5 43 43',
+  lg: '-21 -21 44 44',
+};
+
+/**
+ * `import {LoadingIndicator} from "@chanzuckerberg/eds";`
+ *
+ * Loading indicators inform users about the wait time, reason, and status of ongoing processes when the layout is unknown
+ *
+ * For screen readers, add a custom `aria-label` to describe what is loading.
+ */
+export const LoadingIndicator = ({
+  ariaLabel = 'loading',
+  className,
+  size = 'md',
+  isVisible: visible = true,
+  ...other
+}: LoadingIndicatorProps) => {
+  const componentClassName = clsx(
+    styles['loading-indicator'],
+    !visible && styles['loading-indicator--invisible'],
+    className,
+  );
+
+  // setting the colors to be transparent since we override in CSS
+  // (and have a lint rule prevent token variable use in components)
+  return (
+    <div
+      aria-busy="true"
+      aria-label={ariaLabel}
+      className={componentClassName}
+      data-testid="oval-loading"
+      role="status"
+      {...other}
+    >
+      <svg
+        data-testid="oval-svg"
+        height={loaderSize[size]}
+        stroke="transparent"
+        viewBox={loaderViewportSize[size]}
+        width={loaderSize[size]}
+        xmlns="http://www.w3.org/2000/svg"
+      >
+        <g fill="none" fillRule="evenodd">
+          <g
+            data-testid="oval-secondary-group"
+            strokeWidth={loaderStrokeSize[size]}
+            transform="translate(1 1)"
+          >
+            <circle
+              cx="0"
+              cy="0"
+              r="20"
+              stroke="transparent"
+              strokeOpacity=".5"
+              strokeWidth={loaderStrokeSize[size]}
+            ></circle>
+            <path d="M20 0c0-9.94-8.06-20-20-20">
+              <animateTransform
+                attributeName="transform"
+                dur="1s"
+                from="0 0 0"
+                repeatCount="indefinite"
+                to="360 0 0"
+                type="rotate"
+              ></animateTransform>
+            </path>
+          </g>
+        </g>
+      </svg>
+    </div>
+  );
+};
+
+LoadingIndicator.displayName = 'LoadingIndicator';