Add asymmetric equality tester to match a string against a regexp

- Also move the asymmetric testers into their own dir for easier
  locating.

[#58120558] Fix #243

src/core/asymmetric_equality/StringMatching.js

@@ -0,0 +1,16 @@
+getJasmineRequireObj().StringMatching = function(j$) {
+
+  function StringMatching(expected) {
+    if (!j$.isString_(expected) && !j$.isA_('RegExp', expected)) {
+      throw new Error('Expected is not a String or a RegExp');
+    }
+
+    this.regexp = new RegExp(expected);
+  }
+
+  StringMatching.prototype.asymmetricMatch = function(other) {
+    return this.regexp.test(other);
+  };
+
+  return StringMatching;
+};

src/core/base.js

@@ -53,6 +53,10 @@ getJasmineRequireObj().base = function(j$, jasmineGlobal) {
     return new j$.ObjectContaining(sample);
   };
 
+  j$.stringMatching = function(expected) {
+    return new j$.StringMatching(expected);
+  };
+
   j$.createSpy = function(name, originalFn) {
 
     var spyStrategy = new j$.SpyStrategy({

src/core/requireCore.js

@@ -36,6 +36,7 @@ getJasmineRequireObj = (function (jasmineGlobal) {
     j$.Spec = jRequire.Spec(j$);
     j$.SpyRegistry = jRequire.SpyRegistry(j$);
     j$.SpyStrategy = jRequire.SpyStrategy();
+    j$.StringMatching = jRequire.StringMatching(j$);
     j$.Suite = jRequire.Suite();
     j$.Timer = jRequire.Timer();
     j$.version = jRequire.version();