Allow building the "c-bindings" program with Bazel

WORKSPACE

@@ -1,5 +1,10 @@
 workspace(name = "google_jsonnet_go")
 
+local_repository(
+    name = "cpp_jsonnet",
+    path = "./cpp-jsonnet",
+)
+
 load(
     "@bazel_tools//tools/build_defs/repo:http.bzl",
     "http_archive",

c-bindings/BUILD.bazel

@@ -9,11 +9,17 @@ go_library(
         "json.h",
         "libjsonnet.cpp",
     ],
+    cdeps = [
+        "@cpp_jsonnet//include:libjsonnet",
+    ],
     cgo = True,
-    copts = ["-std=c++11 -Wall"],
+    copts = ["-Wall -Icpp-jsonnet/include"],  # keep
+    cxxopts = ["-std=c++11"],
     importpath = "github.com/google/go-jsonnet/c-bindings",
     visibility = ["//visibility:private"],
-    deps = ["//:go_default_library"],
+    deps = [
+        "//:go_default_library",
+    ],
 )
 
 go_binary(

c-bindings/c-bindings.go

@@ -7,7 +7,7 @@ import (
 
 	"github.com/google/go-jsonnet"
 
-	// #cgo CXXFLAGS: -std=c++11 -Wall
+	// #cgo CXXFLAGS: -std=c++11 -Wall -I../cpp-jsonnet/include
 	// #include "internal.h"
 	"C"
 )

c-bindings/json.cpp

@@ -1,5 +1,5 @@
 extern "C" {
-    #include "../cpp-jsonnet/include/libjsonnet.h"
+    #include "libjsonnet.h"
 }
 
 #include "json.h"

c-bindings/json.h

@@ -22,8 +22,6 @@ limitations under the License.
 #include <vector>
 #include <map>
 
-#include "../cpp-jsonnet/include/libjsonnet.h"
-
 struct JsonnetJsonValue {
     enum Kind {
         ARRAY,

c-bindings/libjsonnet.cpp

@@ -2,7 +2,7 @@
 #include <stdlib.h>
 
 extern "C" {
-    #include "../cpp-jsonnet/include/libjsonnet.h"
+    #include "libjsonnet.h"
     #include "internal.h"
 }