Add basic sprintf implementation to JavaScript

2 files changed, 29 insertions, 0 deletions

diff --git a/app/assets/javascripts/locale/index.js b/app/assets/javascripts/locale/index.js
index 7ba676d6d20..29dcd64df87 100644
--- a/app/assets/javascripts/locale/index.js
+++ b/app/assets/javascripts/locale/index.js
@@ -1,5 +1,7 @@
 import Jed from 'jed';
 
+import sprintf from './sprintf';
+
 /**
   This is required to require all the translation folders in the current directory
   this saves us having to do this manually & keep up to date with new languages
@@ -67,4 +69,5 @@ export { lang };
 export { gettext as __ };
 export { ngettext as n__ };
 export { pgettext as s__ };
+export { sprintf };
 export default locale;
diff --git a/app/assets/javascripts/locale/sprintf.js b/app/assets/javascripts/locale/sprintf.js
new file mode 100644
index 00000000000..003cbe820d6
--- /dev/null
+++ b/app/assets/javascripts/locale/sprintf.js
@@ -0,0 +1,26 @@
+import _ from 'underscore';
+
+/**
+  Very limited implementation of sprintf supporting only named parameters.
+
+  @param input (translated) text with parameters (e.g. '%{num_users} users use us')
+  @param parameters object mapping parameter names to values (e.g. { num_users: 5 })
+  @param escapeParameters whether parameter values should be escaped (see http://underscorejs.org/#escape)
+  @returns {String} the text with parameters replaces (e.g. '5 users use us')
+
+  @see https://ruby-doc.org/core-2.3.3/Kernel.html#method-i-sprintf
+  @see https://gitlab.com/gitlab-org/gitlab-ce/issues/37992
+**/
+export default (input, parameters, escapeParameters = true) => {
+    let output = input;
+
+    if (parameters) {
+      Object.keys(parameters).forEach((parameterName) => {
+        const parameterValue = parameters[parameterName];
+        const escapedParameterValue = escapeParameters ? _.escape(parameterValue) : parameterValue;
+        output = output.replace(new RegExp(`%{${parameterName}}`, 'g'), escapedParameterValue);
+      });
+    }
+
+    return output;
+}