From 0b14d695392002c12e43a110ecc3a29dbfcb5f19 Mon Sep 17 00:00:00 2001
From: Mateusz Pusz <mateusz.pusz@gmail.com>
Date: Wed, 5 Feb 2025 12:08:32 +0100
Subject: [PATCH] feat: `quantity::one()` removed

Related to #408
---
 src/core/include/mp-units/framework/quantity.h |  6 ------
 src/core/include/mp-units/math.h               |  8 ++++----
 test/runtime/distribution_test.cpp             | 12 ++++++------
 test/static/quantity_test.cpp                  |  2 --
 4 files changed, 10 insertions(+), 18 deletions(-)

diff --git a/src/core/include/mp-units/framework/quantity.h b/src/core/include/mp-units/framework/quantity.h
index fe211ff4..9703bb77 100644
--- a/src/core/include/mp-units/framework/quantity.h
+++ b/src/core/include/mp-units/framework/quantity.h
@@ -148,12 +148,6 @@ public:
     return {representation_values<rep>::zero(), R};
   }
 
-  [[nodiscard]] static constexpr quantity one() noexcept
-    requires requires { representation_values<rep>::one(); }
-  {
-    return {representation_values<rep>::one(), R};
-  }
-
   [[nodiscard]] static constexpr quantity min() noexcept
     requires requires { representation_values<rep>::min(); }
   {
diff --git a/src/core/include/mp-units/math.h b/src/core/include/mp-units/math.h
index 420472db..fb458f9e 100644
--- a/src/core/include/mp-units/math.h
+++ b/src/core/include/mp-units/math.h
@@ -84,7 +84,7 @@ template<std::intmax_t Num, std::intmax_t Den = 1, auto R, typename Rep>
 
 {
   if constexpr (Num == 0) {
-    return quantity<pow<Num, Den>(R), Rep>::one();
+    return {representation_values<Rep>::one(), pow<0>(R)};
   } else if constexpr (Num == Den) {
     return q;
   } else {
@@ -341,7 +341,7 @@ template<Unit auto To, auto R, typename Rep>
 {
   const auto handle_signed_results = [&]<typename T>(const T& res) {
     if (res > q) {
-      return res - T::one();
+      return res - representation_values<Rep>::one() * T::reference;
     }
     return res;
   };
@@ -378,7 +378,7 @@ template<Unit auto To, auto R, typename Rep>
 {
   const auto handle_signed_results = [&]<typename T>(const T& res) {
     if (res < q) {
-      return res + T::one();
+      return res + representation_values<Rep>::one() * T::reference;
     }
     return res;
   };
@@ -424,7 +424,7 @@ template<Unit auto To, auto R, typename Rep>
     }
   } else {
     const auto res_low = mp_units::floor<To>(q);
-    const auto res_high = res_low + res_low.one();
+    const auto res_high = res_low + representation_values<Rep>::one() * res_low.reference;
     const auto diff0 = q - res_low;
     const auto diff1 = res_high - q;
     if (diff0 == diff1) {
diff --git a/test/runtime/distribution_test.cpp b/test/runtime/distribution_test.cpp
index 1ea3da1d..19b237a0 100644
--- a/test/runtime/distribution_test.cpp
+++ b/test/runtime/distribution_test.cpp
@@ -83,7 +83,7 @@ TEST_CASE("distributions", "[random][distribution]")
       auto dist = mp_units::uniform_real_distribution<q>();
 
       CHECK(dist.a() == q::zero());
-      CHECK(dist.b() == q::one());
+      CHECK(dist.b() == 1 * si::metre);
     }
 
     SECTION("parametrized")
@@ -111,7 +111,7 @@ TEST_CASE("distributions", "[random][distribution]")
       auto dist = mp_units::binomial_distribution<q>();
 
       CHECK(dist.p() == 0.5);
-      CHECK(dist.t() == q::one());
+      CHECK(dist.t() == 1 * si::metre);
     }
 
     SECTION("parametrized")
@@ -139,7 +139,7 @@ TEST_CASE("distributions", "[random][distribution]")
       auto dist = mp_units::negative_binomial_distribution<q>();
 
       CHECK(dist.p() == 0.5);
-      CHECK(dist.k() == q::one());
+      CHECK(dist.k() == 1 * si::metre);
     }
 
     SECTION("parametrized")
@@ -326,7 +326,7 @@ TEST_CASE("distributions", "[random][distribution]")
       auto dist = mp_units::normal_distribution<q>();
 
       CHECK(dist.mean() == q::zero());
-      CHECK(dist.stddev() == q::one());
+      CHECK(dist.stddev() == 1 * si::metre);
     }
 
     SECTION("parametrized")
@@ -354,7 +354,7 @@ TEST_CASE("distributions", "[random][distribution]")
       auto dist = mp_units::lognormal_distribution<q>();
 
       CHECK(dist.m() == q::zero());
-      CHECK(dist.s() == q::one());
+      CHECK(dist.s() == 1 * si::metre);
     }
 
     SECTION("parametrized")
@@ -407,7 +407,7 @@ TEST_CASE("distributions", "[random][distribution]")
       auto dist = mp_units::cauchy_distribution<q>();
 
       CHECK(dist.a() == q::zero());
-      CHECK(dist.b() == q::one());
+      CHECK(dist.b() == 1 * si::metre);
     }
 
     SECTION("parametrized")
diff --git a/test/static/quantity_test.cpp b/test/static/quantity_test.cpp
index 8e3f44e8..7ae481be 100644
--- a/test/static/quantity_test.cpp
+++ b/test/static/quantity_test.cpp
@@ -162,11 +162,9 @@ static_assert(is_same_v<decltype(quantity(vint, m))::rep, std::int16_t>);
 ////////////////////////////
 
 static_assert(quantity<isq::length[m], int>::zero().numerical_value_in(m) == 0);
-static_assert(quantity<isq::length[m], int>::one().numerical_value_in(m) == 1);
 static_assert(quantity<isq::length[m], int>::min().numerical_value_in(m) == std::numeric_limits<int>::lowest());
 static_assert(quantity<isq::length[m], int>::max().numerical_value_in(m) == std::numeric_limits<int>::max());
 static_assert(quantity<isq::length[m], double>::zero().numerical_value_in(m) == 0.0);
-static_assert(quantity<isq::length[m], double>::one().numerical_value_in(m) == 1.0);
 static_assert(quantity<isq::length[m], double>::min().numerical_value_in(m) == std::numeric_limits<double>::lowest());
 static_assert(quantity<isq::length[m], double>::max().numerical_value_in(m) == std::numeric_limits<double>::max());