fix($urlMatcherFactory): make optional params regex grouping optional

- Previously, the optional parameter's pattern itself was assumed to match 0-length strings
- That did not work if a regexp that was provided for a param required at least one character , ie, [A-Z0-9]{10,16}
- Now, we wrap the pattern group with a question mark if the parameter is optional (pattern)?

Closes #1576

Author: christopherthielen

src/urlMatcherFactory.js

@@ -98,13 +98,13 @@ function UrlMatcher(pattern, config, parentMatcher) {
     return params[id];
   }
 
-  function quoteRegExp(string, pattern, squash) {
+  function quoteRegExp(string, pattern, squash, optional) {
     var surroundPattern = ['',''], result = string.replace(/[\\\[\]\^$*+?.()|{}]/g, "\\$&");
     if (!pattern) return result;
     switch(squash) {
-      case false: surroundPattern = ['(', ')'];   break;
+      case false: surroundPattern = ['(', ')' + (optional ? "?" : "")]; break;
       case true:  surroundPattern = ['?(', ')?']; break;
-      default:    surroundPattern = ['(' + squash + "|", ')?'];  break;
+      default:    surroundPattern = ['(' + squash + "|", ')?']; break;
     }
     return result + surroundPattern[0] + pattern + surroundPattern[1];
   }
@@ -131,7 +131,7 @@ function UrlMatcher(pattern, config, parentMatcher) {
     if (p.segment.indexOf('?') >= 0) break; // we're into the search part
 
     param = addParameter(p.id, p.type, p.cfg, "path");
-    compiled += quoteRegExp(p.segment, param.type.pattern.source, param.squash);
+    compiled += quoteRegExp(p.segment, param.type.pattern.source, param.squash, param.isOptional);
     segments.push(p.segment);
     last = placeholder.lastIndex;
   }

test/urlMatcherFactorySpec.js

@@ -645,6 +645,14 @@ describe("urlMatcherFactory", function () {
         expect(m.exec('/users/bar/2')).toBeNull();
       });
 
+      it("should populate even if the regexp requires 1 or more chars", function() {
+        var m = new UrlMatcher('/record/{appId}/{recordId:[0-9a-fA-F]{10,24}}', {
+          params: { appId: null, recordId: null }
+        });
+        expect(m.exec("/record/546a3e4dd273c60780e35df3/"))
+          .toEqual({ appId: "546a3e4dd273c60780e35df3", recordId: null });
+      });
+
       it("should allow shorthand definitions", function() {
         var m = new UrlMatcher('/foo/:foo', {
           params: { foo: "bar" }