Decode operand in filter.js in operator-aware way

When decoding an operand, a + can be converted to a space
only if the operand is not an email address.

(imported from commit 08fc36a579bbe6409137c60c0fa9579fe3ab2c43)

static/js/filter.js

@@ -97,8 +97,11 @@ function encodeOperand(operand) {
                   .replace(/ /g,  '+');
 }
 
-function decodeOperand(encoded) {
-    return util.robust_uri_decode(encoded.replace(/\+/g, ' '));
+function decodeOperand(encoded, operator) {
+    if (operator !== 'pm-with' && operator !== 'sender') {
+        encoded = encoded.replace(/\+/g, ' ');
+    }
+    return util.robust_uri_decode(encoded);
 }
 
 // Parse a string into a list of operators (see below).
@@ -119,7 +122,7 @@ Filter.parse = function (str) {
             // Looks like an operator.
             // FIXME: Should we skip unknown operator names here?
             operator = parts.shift();
-            operators.push([operator, decodeOperand(parts.join(':'))]);
+            operators.push([operator, decodeOperand(parts.join(':'), operator)]);
         }
     });
     // NB: Callers of 'parse' can assume that the 'search' operator is last.

zerver/tests/frontend/node/filter.js

@@ -177,6 +177,18 @@ function get_predicate(operators) {
     string = 'stream:Foo topic:Bar yo';
     assert.deepEqual(Filter.unparse(operators), string);
 
+    string = 'pm-with:leo+test@zulip.com';
+    operators = [['pm-with', 'leo+test@zulip.com']];
+    assert.deepEqual(Filter.parse(string), operators);
+
+    string = 'sender:leo+test@zulip.com';
+    operators = [['sender', 'leo+test@zulip.com']];
+    assert.deepEqual(Filter.parse(string), operators);
+
+    string = 'stream:With+Space';
+    operators = [['stream', 'With Space']];
+    assert.deepEqual(Filter.parse(string), operators);
+
     operators = [['id', 50]];
     string = 'id:50';
     assert.deepEqual(Filter.unparse(operators), string);