css2/test: Set up fuzz testing for the tokenizer

css2/BUILD

@@ -1,5 +1,6 @@
 load("@rules_cc//cc:defs.bzl", "cc_library", "cc_test")
-load("//bzl:copts.bzl", "HASTUR_COPTS")
+load("@rules_fuzzing//fuzzing:cc_defs.bzl", "cc_fuzz_test")
+load("//bzl:copts.bzl", "HASTUR_COPTS", "HASTUR_FUZZ_PLATFORMS")
 
 cc_library(
     name = "css2",
@@ -26,4 +27,17 @@ cc_library(
         ":css2",
         "//etest",
     ],
-) for src in glob(["*_test.cpp"])]
+) for src in glob(
+    include = ["*_test.cpp"],
+    exclude = ["*_fuzz_test.cpp"],
+)]
+
+[cc_fuzz_test(
+    name = src[:-4],
+    size = "small",
+    testonly = True,
+    srcs = [src],
+    copts = HASTUR_COPTS,
+    target_compatible_with = HASTUR_FUZZ_PLATFORMS,
+    deps = [":css2"],
+) for src in glob(["*_fuzz_test.cpp"])]

css2/tokenizer_fuzz_test.cpp

@@ -0,0 +1,21 @@
+// SPDX-FileCopyrightText: 2024 Robin Lindén <[email protected]>
+//
+// SPDX-License-Identifier: BSD-2-Clause
+
+#include "css2/tokenizer.h"
+
+#include <cstddef>
+#include <cstdint>
+#include <string_view>
+
+extern "C" int LLVMFuzzerTestOneInput(std::uint8_t const *data, std::size_t size);
+
+extern "C" int LLVMFuzzerTestOneInput(std::uint8_t const *data, std::size_t size) {
+    auto input = std::string_view{reinterpret_cast<char const *>(data), size};
+    css2::Tokenizer{input,
+            [](auto &&) {},
+            [](auto) {
+            }}
+            .run();
+    return 0;
+}