FEATURE: Plugins can overwrite and add support for new icons

app/assets/javascripts/discourse-common/lib/icon-library.js.es6

@@ -0,0 +1,68 @@
+import { h } from 'virtual-dom';
+let _renderers = [];
+
+export function renderIcon(renderType, id, params) {
+  for (let i=0; i<_renderers.length; i++) {
+    let renderer = _renderers[i];
+    let rendererForType = renderer[renderType];
+
+    if (rendererForType) {
+      let result = rendererForType(id, params || {});
+      if (result) {
+        return result;
+      }
+    }
+  }
+}
+
+export function iconHTML(id, params) {
+  return renderIcon('string', id, params);
+}
+
+export function iconNode(id, params) {
+  return renderIcon('node', id, params);
+}
+
+export function registerIconRenderer(renderer) {
+  _renderers.unshift(renderer);
+}
+
+// Support for font awesome icons
+function faClasses(id, params) {
+  let classNames = `fa fa-${id}`;
+  if (params) {
+    if (params.modifier) { classNames += " fa-" + params.modifier; }
+    if (params['class']) { classNames += ' ' + params['class']; }
+  }
+  return classNames;
+}
+
+// default resolver is font awesome
+registerIconRenderer({
+  name: 'font-awesome',
+
+  string(id, params) {
+    let html = `<i class='${faClasses(id, params)}'`;
+    if (params.title) { html += ` title='${I18n.t(params.title)}'`; }
+    if (params.label) { html += " aria-hidden='true'"; }
+    html += "></i>";
+    if (params.label) {
+      html += "<span class='sr-only'>" + I18n.t(params.label) + "</span>";
+    }
+    return html;
+  },
+
+  node(id, params) {
+    const properties = {
+      className: faClasses(id, params),
+      attributes: { "aria-hidden": true }
+    };
+
+    if (params.title) { properties.attributes.title = params.title; }
+    if (params.label) {
+      return h('i', properties, h('span.sr-only', I18n.t(params.label)));
+    } else {
+      return h('i', properties);
+    }
+  }
+});