added unit testing, and started implementing unit tests...phew

node_modules/@sinonjs/commons/lib/deprecated.js

@@ -0,0 +1,40 @@
+/* eslint-disable no-console */
+"use strict";
+
+// wrap returns a function that will invoke the supplied function and print a deprecation warning to the console each
+// time it is called.
+exports.wrap = function(func, msg) {
+    var wrapped = function() {
+        exports.printWarning(msg);
+        return func.apply(this, arguments);
+    };
+    if (func.prototype) {
+        wrapped.prototype = func.prototype;
+    }
+    return wrapped;
+};
+
+// defaultMsg returns a string which can be supplied to `wrap()` to notify the user that a particular part of the
+// sinon API has been deprecated.
+exports.defaultMsg = function(packageName, funcName) {
+    return (
+        packageName +
+        "." +
+        funcName +
+        " is deprecated and will be removed from the public API in a future version of " +
+        packageName +
+        "."
+    );
+};
+
+exports.printWarning = function(msg) {
+    // Watch out for IE7 and below! :(
+    /* istanbul ignore next */
+    if (typeof console !== "undefined") {
+        if (console.info) {
+            console.info(msg);
+        } else {
+            console.log(msg);
+        }
+    }
+};