From 5e351cfd796eefecc8801442f1f8ead9b148c612 Mon Sep 17 00:00:00 2001
From: Chiraffollo <5937599+Chiraffollo@users.noreply.github.com>
Date: Thu, 18 Jul 2024 10:03:03 +0200
Subject: [PATCH] Fix issue #923 equality operator for class expected (#926)

* Add equality operators for class expected

* Add missing unequal operator

---------

Co-authored-by: Oliver Marx <omarx@de.pepperl-fuchs.com>
---
 include/etl/expected.h | 71 ++++++++++++++++++++++++++++++++++++++++--
 test/test_expected.cpp | 49 +++++++++++++++++++++++++++++
 2 files changed, 117 insertions(+), 3 deletions(-)

diff --git a/include/etl/expected.h b/include/etl/expected.h
index 0c3dd983e..708a8f861 100644
--- a/include/etl/expected.h
+++ b/include/etl/expected.h
@@ -940,11 +940,76 @@ namespace etl
 //*******************************************
 /// Equivalence operator.
 //*******************************************
-template <typename TError>
+template <typename TValue, typename TError, typename TValue2, typename TError2>
+ETL_CONSTEXPR14
+bool operator ==(const etl::expected<TValue, TError>& lhs, const etl::expected<TValue2, TError2>& rhs)
+{
+  if (lhs.has_value() != rhs.has_value())
+  {
+    return false;
+  }
+  if (lhs.has_value())
+  {
+    return lhs.value() == rhs.value();
+  }
+  return lhs.error() == rhs.error();
+}
+
+template <typename TValue, typename TError, typename TValue2>
+ETL_CONSTEXPR14
+bool operator ==(const etl::expected<TValue, TError>& lhs, const TValue2& rhs)
+{
+  if (!lhs.has_value())
+  {
+    return false;
+  }
+  return lhs.value() == rhs;
+}
+
+template <typename TValue, typename TError, typename TError2>
+ETL_CONSTEXPR14
+bool operator ==(const etl::expected<TValue, TError>& lhs, const etl::unexpected<TError2>& rhs)
+{
+  if (lhs.has_value())
+  {
+    return false;
+  }
+  return lhs.error() == rhs;
+}
+
+template <typename TError, typename TError2>
+ETL_CONSTEXPR14
+bool operator ==(const etl::unexpected<TError>& lhs, const etl::unexpected<TError2>& rhs)
+{
+  return lhs.error() == rhs.error();
+}
+
+template <typename TValue, typename TError, typename TValue2, typename TError2>
+ETL_CONSTEXPR14
+bool operator !=(const etl::expected<TValue, TError>& lhs, const etl::expected<TValue2, TError2>& rhs)
+{
+  return !(lhs == rhs);
+}
+
+template <typename TValue, typename TError, typename TValue2>
+ETL_CONSTEXPR14
+bool operator !=(const etl::expected<TValue, TError>& lhs, const TValue2& rhs)
+{
+  return !(lhs == rhs);
+}
+
+template <typename TValue, typename TError, typename TError2>
+ETL_CONSTEXPR14
+bool operator !=(const etl::expected<TValue, TError>& lhs, const etl::unexpected<TError2>& rhs)
+{
+  return !(lhs == rhs);
+}
+
+template <typename TError, typename TError2>
 ETL_CONSTEXPR14
-bool operator ==(const etl::unexpected<TError>& lhs, const etl::unexpected<TError>& rhs)
+bool operator !=(const etl::unexpected<TError>& lhs, const etl::unexpected<TError2>& rhs)
 {
-  return lhs.error_value == rhs.error_value;
+  return !(lhs == rhs);
 }
 
 //*******************************************
diff --git a/test/test_expected.cpp b/test/test_expected.cpp
index a199707a0..ce6b78482 100644
--- a/test/test_expected.cpp
+++ b/test/test_expected.cpp
@@ -629,5 +629,54 @@ namespace
       CHECK_TRUE(thrown);
       CHECK_TRUE(exception_what == thrown_what);
     }
+
+    //*************************************************************************
+    TEST(test_expected_equal_operator)
+    {
+      etl::expected<int, int> test_exp = 1;
+      etl::expected<int, int> test_exp_equal = 1;
+      etl::expected<int, int> test_exp_unequal = 2;
+      int test_val_equal = 1;
+      int test_val_unequal = 2;
+      etl::expected<int, int> test_unexp = etl::unexpected<int>(1);
+      etl::expected<int, int> test_unexp_equal = etl::unexpected<int>(1);
+      etl::expected<int, int> test_unexp_unequal = etl::unexpected<int>(2);
+
+      CHECK_TRUE(test_exp == test_exp_equal);
+      CHECK_FALSE(test_exp != test_exp_equal);
+
+      CHECK_FALSE(test_exp == test_exp_unequal);
+      CHECK_TRUE(test_exp != test_exp_unequal);
+
+      CHECK_TRUE(test_exp == test_val_equal);
+      CHECK_FALSE(test_exp != test_val_equal);
+
+      CHECK_FALSE(test_exp == test_val_unequal);
+      CHECK_TRUE(test_exp != test_val_unequal);
+
+      CHECK_FALSE(test_exp == test_unexp);
+      CHECK_TRUE(test_exp != test_unexp);
+
+      CHECK_TRUE(test_unexp == test_unexp_equal);
+      CHECK_FALSE(test_unexp != test_unexp_equal);
+
+      CHECK_FALSE(test_unexp == test_unexp_unequal);
+      CHECK_TRUE(test_unexp != test_unexp_unequal);
+    }
+
+
+    //*************************************************************************
+    TEST(test_unexpected_equal_operator)
+    {
+      etl::unexpected<int> test_unexp = etl::unexpected<int>(1);
+      etl::unexpected<int> test_unexp_equal = etl::unexpected<int>(1);
+      etl::unexpected<int> test_unexp_unequal = etl::unexpected<int>(2);
+
+      CHECK_TRUE(test_unexp == test_unexp_equal);
+      CHECK_FALSE(test_unexp != test_unexp_equal);
+
+      CHECK_FALSE(test_unexp == test_unexp_unequal);
+      CHECK_TRUE(test_unexp != test_unexp_unequal);
+    }
   };
 }