From b29adaa53f2cf764898fe53bceea66756a067e29 Mon Sep 17 00:00:00 2001
From: Yohan Boniface <yb@enix.org>
Date: Sun, 8 Nov 2020 12:07:07 +0100
Subject: [PATCH] Minimal fallback handling in templating

eg. {var|defaultvalue}

cf #820
---
 umap/static/umap/js/umap.core.js | 4 ++--
 umap/static/umap/test/Util.js    | 4 ++++
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/umap/static/umap/js/umap.core.js b/umap/static/umap/js/umap.core.js
index 1f3f8cbf..0bbdb6ea 100644
--- a/umap/static/umap/js/umap.core.js
+++ b/umap/static/umap/js/umap.core.js
@@ -126,14 +126,14 @@ L.Util.usableOption = function (options, option) {
 
 L.Util.greedyTemplate = function (str, data, ignore) {
     // Don't throw error if some key is missing
-    return str.replace(/\{ *([\w_\:\.]+) *\}/g, function (str, key) {
+    return str.replace(/\{ *([\w_\:\.]+)(\|([^\}]+))? *\}/g, function (str, key, _, fallback) {
         var path = key.split('.'),
             leaf = path.length - 1, value = data;
         for (var i = 0; i < path.length; i++) {
             value = value[path[i]]
             if (value === undefined) {
                 if (ignore) value = str;
-                else value = '';
+                else value = fallback || '';
                 break;
             }
         }
diff --git a/umap/static/umap/test/Util.js b/umap/static/umap/test/Util.js
index 03004efc..fd6b5ebf 100644
--- a/umap/static/umap/test/Util.js
+++ b/umap/static/umap/test/Util.js
@@ -166,6 +166,10 @@ describe('L.Util', function () {
             assert.equal(L.Util.greedyTemplate('A phrase with a {fr.var.foo}.', {}), 'A phrase with a .');
         });
 
+        it('should handle fallback value if any', function () {
+            assert.equal(L.Util.greedyTemplate('A phrase with a {fr.var.foo|default}.', {}), 'A phrase with a default.');
+        });
+
     });
 
     describe('#TextColorFromBackgroundColor', function () {