zulip/static/js/templates.js

110 lines
3.3 KiB
JavaScript

const util = require("./util");
// Below, we register Zulip-specific extensions to the handlebars API.
//
// IMPORTANT: When adding a new handlebars helper, update the
// knownHelpers array in the webpack config so that webpack knows your
// helper is registered at runtime and don't try to require them when
// bundling.
// We don't want to wait for DOM ready to register the Handlebars helpers
// below. There's no need to, as they do not access the DOM.
// Furthermore, waiting for DOM ready would introduce race conditions with
// other DOM-ready callbacks that attempt to render templates.
Handlebars.registerHelper("plural", (condition, one, other) => (condition === 1 ? one : other));
Handlebars.registerHelper({
eq(a, b) {
return a === b;
},
and(...args) {
args.pop(); // Handlebars options
if (args.length === 0) {
return true;
}
const last = args.pop();
for (const arg of args) {
if (!arg || Handlebars.Utils.isEmpty(arg)) {
return arg;
}
}
return last;
},
or(...args) {
args.pop(); // Handlebars options
if (args.length === 0) {
return false;
}
const last = args.pop();
for (const arg of args) {
if (arg && !Handlebars.Utils.isEmpty(arg)) {
return arg;
}
}
return last;
},
not(a) {
return !a || Handlebars.Utils.isEmpty(a);
},
});
// Note that this i18n caching strategy does not allow us to support
// live-updating the UI language without reloading the Zulip browser
// window. That constraint would be very hard to change in any case,
// though, because of how Zulip renders some strings using the backend
// Jinja2 templating engine, so we don't consider this important.
const t_cache = new Map();
Handlebars.registerHelper("t", (i18n_key) => {
// Marks a string for translation.
// Example usage:
// {{t "some English text"}}
const cache_result = t_cache.get(i18n_key);
if (cache_result !== undefined) {
return cache_result;
}
const result = i18n.t(i18n_key);
const safe_result = new Handlebars.SafeString(result);
t_cache.set(i18n_key, safe_result);
return safe_result;
});
Handlebars.registerHelper("tr", (context, options) => {
// Marks a block for translation.
// Example usage 1:
// {{#tr context}}
// <p>some English text</p>
// {{/tr}}
//
// Example usage 2:
// {{#tr context}}
// <p>This __variable__ will get value from context</p>
// {{/tr}}
//
// Notes:
// 1. `context` is very important. It can be `this` or an
// object or key of the current context.
// 2. Use `__` instead of `{{` and `}}` to declare expressions
const result = i18n.t(
options
.fn(context)
.trim()
.split("\n")
.map((s) => s.trim())
.join(" "),
context,
);
return new Handlebars.SafeString(result);
});
Handlebars.registerHelper(
"rendered_markdown",
(content) => new Handlebars.SafeString(util.clean_user_content_links(content)),
);
Handlebars.registerHelper("numberFormat", (number) => number.toLocaleString());
window.templates = exports;