Simplify Bazel

Please see #309 for context, but this sidesteps the bazel dependencies and cleans up the copts where they're not actually used.

BUILD.bazel

@@ -1,6 +1,3 @@
-load("@rules_cc//cc:defs.bzl", "cc_library")
-load("//bazel:copts.bzl", "COPTS")
-
 licenses(["notice"])
 
 exports_files(["LICENSE"])
@@ -10,6 +7,5 @@ package(default_visibility = ["//visibility:public"])
 cc_library(
     name = "magic_enum",
     hdrs = glob(["include/magic_enum/*.hpp"]),
-    copts = COPTS,
-    includes = ["include"],
+    includes = ["include/magic_enum"],
 )

MODULE.bazel

@@ -3,6 +3,3 @@ module(
     version = "0.9.4",
     compatibility_level = 0,
 )
-
-bazel_dep(name = "rules_cc", version = "0.0.8")
-bazel_dep(name = "bazel_skylib", version = "1.4.2")

test/BUILD.bazel

@@ -1,23 +1,25 @@
-load("@rules_cc//cc:defs.bzl", "cc_test")
-load("@magic_enum//bazel:copts.bzl", "COPTS")
-
-# bazel central registry has a catch2 module, but is newer than the one included
-# in this repository
-cc_library(
-    name = "catch2",
-    includes = ["3rdparty/Catch2/include"],
-    hdrs = ["3rdparty/Catch2/include/catch2/catch.hpp"],
-    copts = COPTS,
-)
-
 _TESTS = [
     "test",
     "test_flags",
 ]
 
+_MSVC_FLAGS = ["/std:c++17", "/permissive-"]
+_COPTS = select({
+    "//conditions:default": ["-std=c++17"],
+    "@rules_cc//cc/compiler:msvc-cl": _MSVC_FLAGS,
+    "@rules_cc//cc/compiler:clang-cl": _MSVC_FLAGS, 
+})
 [cc_test(
     name = test,
     srcs = ["{}.cpp".format(test)],
     deps = ["@magic_enum", ":catch2"],
-    copts = COPTS,
+    copts = _COPTS,
 ) for test in _TESTS]
+
+# bazel central registry has a catch2 module, but is newer than the one included
+# in this repository
+cc_library(
+    name = "catch2",
+    includes = ["3rdparty/Catch2/include"],
+    hdrs = ["3rdparty/Catch2/include/catch2/catch.hpp"],
+)

test/MODULE.bazel

@@ -1,6 +1,6 @@
 module(name = "magic_enum_tests")
 
 bazel_dep(name = "magic_enum")
-bazel_dep(name = "rules_cc", version = "0.0.8")
-
 local_path_override(module_name = "magic_enum", path = "..")
+
+bazel_dep(name = "rules_cc", version = "0.0.8")