Add a simple test for importing headers

Author: patrickmscott

tests/core/go_library/BUILD.bazel

@@ -28,8 +28,10 @@ go_library(
     srcs = [
         "inc.go",
         "inc_asmhdr.s",
+        "inc_relative.s",
     ],
     importpath = "asm_header",
+    deps = ["//tests/core/headers"],
 )
 
 go_library(

tests/core/go_library/inc_relative.s

@@ -0,0 +1 @@
+#include "../headers/hdr.h"

tests/core/headers/BUILD.bazel

@@ -0,0 +1,11 @@
+load("@io_bazel_rules_go//go:def.bzl", "go_library")
+
+go_library(
+    name = "headers",
+    srcs = [
+        "hdr.go",
+        "hdr.h",
+    ],
+    importpath = "github.com/bazelbuild/rules_go/tests/core/headers",
+    visibility = ["//visibility:public"],
+)

tests/core/headers/hdr.go

@@ -0,0 +1 @@
+package headers