From 2c1faa1bf962ff958fd5101c27eaefc02b140ab4 Mon Sep 17 00:00:00 2001
From: mchodzikiewicz <33954140+mchodzikiewicz@users.noreply.github.com>
Date: Mon, 2 Mar 2020 13:32:56 +0100
Subject: [PATCH] Add optional::has_value() to fulfill C++17's API (#195)

---
 include/etl/optional.h |  9 +++++++++
 test/test_optional.cpp | 11 +++++++++++
 2 files changed, 20 insertions(+)

diff --git a/include/etl/optional.h b/include/etl/optional.h
index 958acf2f..b95cde16 100644
--- a/include/etl/optional.h
+++ b/include/etl/optional.h
@@ -351,6 +351,15 @@ namespace etl
       return valid;
     }
 
+    //***************************************************************************
+    // Check whether optional contains value
+    //***************************************************************************
+    ETL_CONSTEXPR bool has_value() const ETL_NOEXCEPT
+    {
+      return valid;
+    }
+
+
     //***************************************************************************
     /// Get a reference to the value.
     //***************************************************************************
diff --git a/test/test_optional.cpp b/test/test_optional.cpp
index 77b0b687..7e02c390 100644
--- a/test/test_optional.cpp
+++ b/test/test_optional.cpp
@@ -65,28 +65,39 @@ namespace
 
       CHECK(!bool(data1));
       CHECK(!bool(data2));
+      CHECK(!data1.has_value());
+      CHECK(!data2.has_value());
+
 
       data1 = Data("Hello");
       CHECK(bool(data1));
+      CHECK(data1.has_value());
       CHECK_EQUAL(Data("Hello"), data1);
 
       data1 = data2;
       CHECK(!bool(data1));
       CHECK(!bool(data2));
+      CHECK(!data1.has_value());
+      CHECK(!data2.has_value());
 
       data1 = Data("World");
       data2 = data1;
       CHECK(bool(data1));
       CHECK(bool(data2));
+      CHECK(data1.has_value());
+      CHECK(data2.has_value());
 
       etl::optional<Data> data3(data1);
       CHECK(bool(data3));
+      CHECK(data3.has_value());
       CHECK_EQUAL(data1, data3);
 
       etl::optional<Data> data4;
       data4 = Data("Hello");
       data4 = etl::nullopt;
       CHECK(!bool(data4));
+      CHECK(!data4.has_value());
+
     }
 
     //*************************************************************************