[Tests] add coverage for Object.prototype pollution

Author: ljharb

test/index.js

@@ -104,5 +104,26 @@ test('core modules', function (t) {
 		st.end();
 	});
 
+	t.test('Object.prototype pollution', function (st) {
+		var nonKey = 'not a core module';
+		st.teardown(function () {
+			delete Object.prototype.fs;
+			delete Object.prototype.path;
+			delete Object.prototype.http;
+			delete Object.prototype[nonKey];
+		});
+		Object.prototype.fs = false;
+		Object.prototype.path = '>= 999999999';
+		Object.prototype.http = data.http;
+		Object.prototype[nonKey] = true;
+
+		st.equal(isCore('fs'), true, 'fs is a core module even if Object.prototype lies');
+		st.equal(isCore('path'), true, 'path is a core module even if Object.prototype lies');
+		st.equal(isCore('http'), true, 'path is a core module even if Object.prototype matches data');
+		st.equal(isCore(nonKey), false, '"' + nonKey + '" is not a core module even if Object.prototype lies');
+
+		st.end();
+	});
+
 	t.end();
 });