Merge pull request #1263 from cppalliance/inc_dec

Fix return value & type of post-fix increment/decrement

Author: mborland

include/boost/decimal/decimal128_t.hpp

@@ -2013,7 +2013,9 @@ constexpr auto decimal128_t::operator++() noexcept -> decimal128_t&
 
 constexpr auto decimal128_t::operator++(int) noexcept -> decimal128_t
 {
-    return ++(*this);
+    const auto temp {*this};
+    ++(*this);
+    return temp;
 }
 
 constexpr auto decimal128_t::operator--() noexcept -> decimal128_t&
@@ -2025,7 +2027,9 @@ constexpr auto decimal128_t::operator--() noexcept -> decimal128_t&
 
 constexpr auto decimal128_t::operator--(int) noexcept -> decimal128_t
 {
-    return --(*this);
+    const auto temp {*this};
+    --(*this);
+    return temp;
 }
 
 constexpr auto decimal128_t::operator+=(const decimal128_t rhs) noexcept -> decimal128_t&

include/boost/decimal/decimal32_t.hpp

@@ -1099,7 +1099,9 @@ constexpr auto decimal32_t::operator++() noexcept -> decimal32_t&
 
 constexpr auto decimal32_t::operator++(int) noexcept -> decimal32_t
 {
-    return ++(*this);
+    const auto temp {*this};
+    ++(*this);
+    return temp;
 }
 
 constexpr auto decimal32_t::operator+=(const decimal32_t rhs) noexcept -> decimal32_t&
@@ -1221,7 +1223,9 @@ constexpr auto decimal32_t::operator--() noexcept -> decimal32_t&
 
 constexpr auto decimal32_t::operator--(int) noexcept -> decimal32_t
 {
-    return --(*this);
+    const auto temp {*this};
+    --(*this);
+    return temp;
 }
 
 constexpr auto decimal32_t::operator-=(const decimal32_t rhs) noexcept -> decimal32_t&

include/boost/decimal/decimal64_t.hpp

@@ -1992,7 +1992,9 @@ constexpr auto decimal64_t::operator++() noexcept -> decimal64_t&
 
 constexpr auto decimal64_t::operator++(int) noexcept -> decimal64_t
 {
-    return ++(*this);
+    const auto temp {*this};
+    ++(*this);
+    return temp;
 }
 
 constexpr auto decimal64_t::operator--() noexcept -> decimal64_t&
@@ -2004,7 +2006,9 @@ constexpr auto decimal64_t::operator--() noexcept -> decimal64_t&
 
 constexpr auto decimal64_t::operator--(int) noexcept -> decimal64_t
 {
-    return --(*this);
+    const auto temp {*this};
+    --(*this);
+    return temp;
 }
 
 constexpr auto decimal64_t::operator+=(const decimal64_t rhs) noexcept -> decimal64_t&

include/boost/decimal/decimal_fast128_t.hpp

@@ -1472,7 +1472,9 @@ constexpr auto decimal_fast128_t::operator++() noexcept -> decimal_fast128_t&
 
 constexpr auto decimal_fast128_t::operator++(int) noexcept -> decimal_fast128_t
 {
-    return ++(*this);
+    const auto temp {*this};
+    ++(*this);
+    return temp;
 }
 
 constexpr auto decimal_fast128_t::operator--() noexcept -> decimal_fast128_t&
@@ -1484,7 +1486,9 @@ constexpr auto decimal_fast128_t::operator--() noexcept -> decimal_fast128_t&
 
 constexpr auto decimal_fast128_t::operator--(int) noexcept -> decimal_fast128_t
 {
-    return --(*this);
+    const auto temp {*this};
+    --(*this);
+    return temp;
 }
 
 constexpr decimal_fast128_t::operator bool() const noexcept

include/boost/decimal/decimal_fast32_t.hpp

@@ -420,9 +420,9 @@ BOOST_DECIMAL_EXPORT class decimal_fast32_t final
 
     // Increment and decrement
     constexpr auto operator++() noexcept -> decimal_fast32_t&;
-    constexpr auto operator++(int) noexcept -> decimal_fast32_t&;
+    constexpr auto operator++(int) noexcept -> decimal_fast32_t;
     constexpr auto operator--() noexcept -> decimal_fast32_t&;
-    constexpr auto operator--(int) noexcept -> decimal_fast32_t&;
+    constexpr auto operator--(int) noexcept -> decimal_fast32_t;
 
     // 3.2.2.4 Conversion to integral type
     explicit constexpr operator bool() const noexcept;
@@ -1430,9 +1430,11 @@ constexpr auto decimal_fast32_t::operator++() noexcept -> decimal_fast32_t&
     return *this;
 }
 
-constexpr auto decimal_fast32_t::operator++(int) noexcept -> decimal_fast32_t&
+constexpr auto decimal_fast32_t::operator++(int) noexcept -> decimal_fast32_t
 {
-    return ++(*this);
+    const auto temp {*this};
+    ++(*this);
+    return temp;
 }
 
 constexpr auto decimal_fast32_t::operator--() noexcept -> decimal_fast32_t&
@@ -1442,9 +1444,11 @@ constexpr auto decimal_fast32_t::operator--() noexcept -> decimal_fast32_t&
     return *this;
 }
 
-constexpr auto decimal_fast32_t::operator--(int) noexcept -> decimal_fast32_t&
+constexpr auto decimal_fast32_t::operator--(int) noexcept -> decimal_fast32_t
 {
-    return --(*this);
+    const auto temp {*this};
+    --(*this);
+    return temp;
 }
 
 constexpr decimal_fast32_t::operator bool() const noexcept

include/boost/decimal/decimal_fast64_t.hpp

@@ -482,9 +482,9 @@ BOOST_DECIMAL_EXPORT class decimal_fast64_t final
 
     // Increment and decrement
     constexpr auto operator++() noexcept -> decimal_fast64_t&;
-    constexpr auto operator++(int) noexcept -> decimal_fast64_t&;
+    constexpr auto operator++(int) noexcept -> decimal_fast64_t;
     constexpr auto operator--() noexcept -> decimal_fast64_t&;
-    constexpr auto operator--(int) noexcept -> decimal_fast64_t&;
+    constexpr auto operator--(int) noexcept -> decimal_fast64_t;
 
     // Cmath friend functions
     template <BOOST_DECIMAL_DECIMAL_FLOATING_TYPE T>
@@ -1573,9 +1573,11 @@ constexpr auto decimal_fast64_t::operator++() noexcept -> decimal_fast64_t&
     return *this;
 }
 
-constexpr auto decimal_fast64_t::operator++(int) noexcept -> decimal_fast64_t&
+constexpr auto decimal_fast64_t::operator++(int) noexcept -> decimal_fast64_t
 {
-    return ++(*this);
+    const auto temp {*this};
+    ++(*this);
+    return temp;
 }
 
 constexpr auto decimal_fast64_t::operator--() noexcept -> decimal_fast64_t&
@@ -1585,9 +1587,11 @@ constexpr auto decimal_fast64_t::operator--() noexcept -> decimal_fast64_t&
     return *this;
 }
 
-constexpr auto decimal_fast64_t::operator--(int) noexcept -> decimal_fast64_t&
+constexpr auto decimal_fast64_t::operator--(int) noexcept -> decimal_fast64_t
 {
-    return --(*this);
+    const auto temp {*this};
+    --(*this);
+    return temp;
 }
 
 // Effects: if x is finite, returns its quantum exponent.

test/test_decimal32_fast_basis.cpp

@@ -212,7 +212,7 @@ void test_addition()
 
     // Pre- and post- increment
     BOOST_TEST_EQ(mutable_one, one);
-    BOOST_TEST_EQ(mutable_one++, two);
+    BOOST_TEST_EQ(mutable_one++, one);
     BOOST_TEST_EQ(++mutable_one, three);
 
     // Different orders of magnitude
@@ -262,7 +262,7 @@ void test_subtraction()
 
     // Pre- and post- increment
     BOOST_TEST_EQ(mutable_three, three);
-    BOOST_TEST_EQ(mutable_three--, two);
+    BOOST_TEST_EQ(mutable_three--, three);
     BOOST_TEST_EQ(--mutable_three, one);
 
     // Different orders of magnitude

test/test_decimal64_fast_basis.cpp

@@ -192,7 +192,7 @@ void test_addition()
 
     // Pre- and post- increment
     BOOST_TEST_EQ(mutable_one, one);
-    BOOST_TEST_EQ(mutable_one++, two);
+    BOOST_TEST_EQ(mutable_one++, one);
     BOOST_TEST_EQ(++mutable_one, three);
 
     // Different orders of magnitude
@@ -236,7 +236,7 @@ void test_subtraction()
 
     // Pre- and post- increment
     BOOST_TEST_EQ(mutable_three, three);
-    BOOST_TEST_EQ(mutable_three--, two);
+    BOOST_TEST_EQ(mutable_three--, three);
     BOOST_TEST_EQ(--mutable_three, one);
 
     // Different orders of magnitude