Add preprocessor and unit_test modules

This change adds two Pigweed modules: pw_preprocessor and pw_unit_test.
The preprocessor module contains header files providing helpful macros
for the C preprocessor. The unit test module contains a starter
implementation of a unit testing framework for Pigweed.

Change-Id: I46e1a4cae1fd8ce36d7840a2e92f8013fb489cde

1 files changed, 66 insertions, 0 deletions

diff --git a/pw_preprocessor/util_test.cc b/pw_preprocessor/util_test.cc
new file mode 100644
index 000000000..0ce027f53
--- /dev/null
+++ b/pw_preprocessor/util_test.cc
@@ -0,0 +1,66 @@
+// Copyright 2019 The Pigweed Authors
+//
+// 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
+//
+//     https://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.
+
+#include "pw_preprocessor/util.h"
+
+#include <cstdint>
+
+#include "pw_unit_test/framework.h"
+
+namespace pw {
+namespace {
+
+TEST(Macros, ArraySize) {
+  uint32_t hello_there[123];
+  static_assert(PW_ARRAY_SIZE(hello_there) == 123);
+
+  char characters[500];
+  static_assert(PW_ARRAY_SIZE(characters) == 500);
+  static_assert(PW_ARRAY_SIZE("2345") == 5);
+
+  struct Object {
+    int a;
+    uint64_t array[2048];
+  };
+  Object objects[404];
+
+  static_assert(PW_ARRAY_SIZE(objects) == 404);
+  static_assert(PW_ARRAY_SIZE(Object::array) == 2048);
+  static_assert(PW_ARRAY_SIZE(objects[1].array) == 2048);
+}
+
+TEST(Macros, UnusedVariable) {
+  int this_is_not_used = 12;
+  PW_UNUSED(this_is_not_used);
+
+  volatile void* volatile wow;
+  wow = nullptr;
+  PW_UNUSED(wow);
+}
+
+#define HELLO hello
+#define WORLD WORLD_IMPL()
+#define WORLD_IMPL() WORLD !
+
+TEST(Macros, Stringify) {
+  EXPECT_STREQ("", PW_STRINGIFY());
+  EXPECT_STREQ("> _ <", PW_STRINGIFY(> _ <));
+  EXPECT_STREQ("hello WORLD !", PW_STRINGIFY(HELLO WORLD));
+  EXPECT_STREQ("hello, WORLD !", PW_STRINGIFY(HELLO, WORLD));
+  EXPECT_STREQ("a, b, c, hello, WORLD ! 2",
+               PW_STRINGIFY(a, b, c, HELLO, WORLD 2));
+}
+
+}  // namespace
+}  // namespace pw