add missing lib

lib/ArduinoJson/test/Polyfills/isInteger.cpp

@@ -0,0 +1,36 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#include <ArduinoJson/Polyfills/isInteger.hpp>
+#include <catch.hpp>
+
+using namespace ArduinoJson::Internals;
+
+TEST_CASE("isInteger()") {
+  SECTION("Null") {
+    REQUIRE_FALSE(isInteger(NULL));
+  }
+
+  SECTION("FloatNotInteger") {
+    REQUIRE_FALSE(isInteger("3.14"));
+    REQUIRE_FALSE(isInteger("-3.14"));
+    REQUIRE_FALSE(isInteger("+3.14"));
+  }
+
+  SECTION("Spaces") {
+    REQUIRE_FALSE(isInteger("42 "));
+    REQUIRE_FALSE(isInteger(" 42"));
+  }
+
+  SECTION("Valid") {
+    REQUIRE(isInteger("42"));
+    REQUIRE(isInteger("-42"));
+    REQUIRE(isInteger("+42"));
+  }
+
+  SECTION("ExtraSign") {
+    REQUIRE_FALSE(isInteger("--42"));
+    REQUIRE_FALSE(isInteger("++42"));
+  }
+}