Add test to check that all feature flags are boolean (#3036)

go/lib/env/BUILD.bazel

@@ -1,4 +1,4 @@
-load("@io_bazel_rules_go//go:def.bzl", "go_library")
+load("@io_bazel_rules_go//go:def.bzl", "go_library", "go_test")
 
 go_library(
     name = "go_default_library",
@@ -30,3 +30,11 @@ go_library(
         "@com_github_uber_jaeger_client_go//config:go_default_library",
     ],
 )
+
+go_test(
+    name = "go_default_test",
+    srcs = ["features_test.go"],
+    data = glob(["testdata/**"]),
+    embed = [":go_default_library"],
+    deps = ["@com_github_stretchr_testify//assert:go_default_library"],
+)

go/lib/env/features_test.go

@@ -0,0 +1,29 @@
+// Copyright 2019 ETH Zurich, Anapaya Systems
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package env
+
+import (
+	"reflect"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAllFeatureFlagsShouldBeBoolean(t *testing.T) {
+	features := reflect.TypeOf(Features{})
+	for i := 0; i < features.NumField(); i++ {
+		assert.Equal(t, reflect.Bool, features.Field(i).Type.Kind())
+	}
+}