arc_unpacker: fix unit tests on aarch64

diff --git a/tests/test_support/audio_support.cc b/tests/test_support/audio_support.cc

index c26022e9..5f50d035 100644

--- a/tests/test_support/audio_support.cc

+++ b/tests/test_support/audio_support.cc

@@ -16,6 +16,7 @@

 // along with arc_unpacker. If not, see <http://www.gnu.org/licenses/>.

 #include "test_support/audio_support.h"

+#include <cstdlib>

 #include "algo/format.h"

 #include "algo/range.h"

 #include "dec/microsoft/wav_audio_decoder.h"

@@ -44,13 +45,42 @@ res::Audio tests::get_test_audio()

 void tests::compare_audio(

     const res::Audio &actual, const res::Audio &expected)

 {

+    // Allow for minor variances in audio samples within the specified

+    // threshold. Floating point calculations in some audio decoders yields

+    // slightly differing results across different CPU architectures.

+    //

+    // Affected tests:

+    //   * tests/dec/cri/hca_audio_decoder_test.cc

+    //   * tests/dec/entis/mio_audio_decoder_test.cc

+    static constexpr int tolerance = 1;

+

     REQUIRE(actual.codec == expected.codec);

     REQUIRE(actual.channel_count == expected.channel_count);

     REQUIRE(actual.sample_rate == expected.sample_rate);

     REQUIRE(actual.bits_per_sample == expected.bits_per_sample);

     REQUIRE(actual.extra_codec_headers == expected.extra_codec_headers);

     REQUIRE(actual.samples.size() == expected.samples.size());

+

+#ifdef __x86_64__

     tests::compare_binary(actual.samples, expected.samples);

+#else

+    tests::compare_binary(

+      actual.samples,

+      expected.samples,

+      [](const bstr& bytes1, const bstr& bytes2) -> bool {

+        const auto samples1 = reinterpret_cast<const s16*>(bytes1.c_str());

+        const auto samples2 = reinterpret_cast<const s16*>(bytes2.c_str());

+        const auto n_samples = bytes1.size() / sizeof(*samples1);

+        // algo::range is a bit incomplete to work with std::all_of

+        for (const int i : algo::range(n_samples)) {

+          if (std::abs(samples1[i] - samples2[i]) > tolerance) {

+            return false;

+          }

+        }

+        return true;

+      }

+    );

+#endif

     REQUIRE(actual.loops.size() == expected.loops.size());

     for (const auto i : algo::range(expected.loops.size()))

diff --git a/tests/test_support/common.cc b/tests/test_support/common.cc

index b63ffa89..265ef7b1 100644

--- a/tests/test_support/common.cc

+++ b/tests/test_support/common.cc

@@ -40,3 +40,19 @@ void au::tests::compare_binary(const bstr &actual, const bstr &expected)

     INFO(actual_dump << " != " << expected_dump);

     REQUIRE(actual == expected);

 }

+

+void au::tests::compare_binary(

+    const bstr &actual,

+    const bstr &expected,

+    std::function<bool(const bstr &, const bstr &)> compare)

+{

+    const auto max_size = 10000;

+    auto actual_dump = algo::hex(actual);

+    auto expected_dump = algo::hex(expected);

+    if (actual_dump.size() > max_size)

+        actual_dump = actual_dump.substr(0, max_size) + "(...)";

+    if (expected_dump.size() > max_size)

+        expected_dump = expected_dump.substr(0, max_size) + "(...)";

+    INFO(actual_dump << " != " << expected_dump);

+    REQUIRE(compare(actual, expected));

+}

diff --git a/tests/test_support/common.h b/tests/test_support/common.h

index 7d8be579..ecd5dcf8 100644

--- a/tests/test_support/common.h

+++ b/tests/test_support/common.h

@@ -17,6 +17,7 @@

 #pragma once

+#include <functional>

 #include "io/path.h"

 #include "types.h"

@@ -27,4 +28,9 @@ namespace tests {

     void compare_binary(const bstr &actual, const bstr &expected);

+    void compare_binary(

+        const bstr &actual,

+        const bstr &expected,

+        std::function<bool(const bstr &, const bstr &)> compare);

+

 } }

  };

  patches = [

    ./fix-test-float-variance.patch

    (fetchpatch {

      name = "failing_tests.patch";

      url = "https://aur.archlinux.org/cgit/aur.git/plain/failing_tests.patch?h=arc_unpacker-git&id=bda1ad9f69e6802e703b2e6913d71a36d76cfef9";

    runHook postInstall

  '';

  # A few tests fail on aarch64-linux

  doCheck = !(stdenv.hostPlatform.isLinux && stdenv.hostPlatform.isAarch64);

  doCheck = true;

  meta = with lib; {

    description = "Tool to extract files from visual novel archives";

    maintainers = with maintainers; [ midchildan ];

    platforms = platforms.all;

    mainProgram = "arc_unpacker";

    # unit test failures

    broken = stdenv.hostPlatform.isDarwin && stdenv.hostPlatform.isAarch64;

  };

}