Fix #157

lib/ext/contain.js

@@ -138,7 +138,7 @@ export default function(should, Assertion) {
     this.params = { operator: "to contain " + i(other) };
 
     var obj = this.obj;
-    if (typeof obj == "string") {
+    if (typeof obj === "string" && typeof other === "string") {
       // expect other to be string
       this.is.equal(String(other));
     } else if (isIterable(obj) && isIterable(other)) {

test/ext/contain.test.js

@@ -54,6 +54,7 @@ describe("contain*", function() {
     [1, 2, 3].should.containDeep([3, 2]);
 
     ["code-for-days", "code"].should.containDeep(["code", "code-for-days"]);
+    ({ a: "hello" }.should.not.containDeep({ a: ["hello"] }));
     ["code-for-days", "code-fast"].should.containDeep(["code-fast", "code-for-days"]);
 
     err(function() {