1 files changed, 117 insertions, 0 deletions
diff --git a/app/javascript/mastodon/components/short_number.jsx b/app/javascript/mastodon/components/short_number.jsx
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index 000000000..535c17727
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+++ b/app/javascript/mastodon/components/short_number.jsx
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+import React from 'react';
+import PropTypes from 'prop-types';
+import { toShortNumber, pluralReady, DECIMAL_UNITS } from '../utils/numbers';
+import { FormattedMessage, FormattedNumber } from 'react-intl';
+// @ts-check
+
+/**
+ * @callback ShortNumberRenderer
+ * @param {JSX.Element} displayNumber Number to display
+ * @param {number} pluralReady Number used for pluralization
+ * @returns {JSX.Element} Final render of number
+ */
+
+/**
+ * @typedef {object} ShortNumberProps
+ * @property {number} value Number to display in short variant
+ * @property {ShortNumberRenderer} [renderer]
+ * Custom renderer for numbers, provided as a prop. If another renderer
+ * passed as a child of this component, this prop won't be used.
+ * @property {ShortNumberRenderer} [children]
+ * Custom renderer for numbers, provided as a child. If another renderer
+ * passed as a prop of this component, this one will be used instead.
+ */
+
+/**
+ * Component that renders short big number to a shorter version
+ *
+ * @param {ShortNumberProps} param0 Props for the component
+ * @returns {JSX.Element} Rendered number
+ */
+function ShortNumber({ value, renderer, children }) {
+  const shortNumber = toShortNumber(value);
+  const [, division] = shortNumber;
+
+  // eslint-disable-next-line eqeqeq
+  if (children != null && renderer != null) {
+    console.warn('Both renderer prop and renderer as a child provided. This is a mistake and you really should fix that. Only renderer passed as a child will be used.');
+  }
+
+  // eslint-disable-next-line eqeqeq
+  const customRenderer = children != null ? children : renderer;
+
+  const displayNumber = <ShortNumberCounter value={shortNumber} />;
+
+  // eslint-disable-next-line eqeqeq
+  return customRenderer != null
+    ? customRenderer(displayNumber, pluralReady(value, division))
+    : displayNumber;
+}
+
+ShortNumber.propTypes = {
+  value: PropTypes.number.isRequired,
+  renderer: PropTypes.func,
+  children: PropTypes.func,
+};
+
+/**
+ * @typedef {object} ShortNumberCounterProps
+ * @property {import('../utils/number').ShortNumber} value Short number
+ */
+
+/**
+ * Renders short number into corresponding localizable react fragment
+ *
+ * @param {ShortNumberCounterProps} param0 Props for the component
+ * @returns {JSX.Element} FormattedMessage ready to be embedded in code
+ */
+function ShortNumberCounter({ value }) {
+  const [rawNumber, unit, maxFractionDigits = 0] = value;
+
+  const count = (
+    <FormattedNumber
+      value={rawNumber}
+      maximumFractionDigits={maxFractionDigits}
+    />
+  );
+
+  let values = { count, rawNumber };
+
+  switch (unit) {
+  case DECIMAL_UNITS.THOUSAND: {
+    return (
+      <FormattedMessage
+        id='units.short.thousand'
+        defaultMessage='{count}K'
+        values={values}
+      />
+    );
+  }
+  case DECIMAL_UNITS.MILLION: {
+    return (
+      <FormattedMessage
+        id='units.short.million'
+        defaultMessage='{count}M'
+        values={values}
+      />
+    );
+  }
+  case DECIMAL_UNITS.BILLION: {
+    return (
+      <FormattedMessage
+        id='units.short.billion'
+        defaultMessage='{count}B'
+        values={values}
+      />
+    );
+  }
+  // Not sure if we should go farther - @Sasha-Sorokin
+  default: return count;
+  }
+}
+
+ShortNumberCounter.propTypes = {
+  value: PropTypes.arrayOf(PropTypes.number),
+};
+
+export default React.memo(ShortNumber);