From 719f71c5658d899051d08dc1362da4c61b14691c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Steffan=20S=C3=B8lvsten?= <soelvsten@cs.au.dk>
Date: Mon, 12 Feb 2024 17:57:09 +0100
Subject: [PATCH] Add truncation for quantify::transposition_growth

And also coverage for nested::fast_reduce
---
 src/adiar/exec_policy.h         | 15 +++++++++++++--
 test/adiar/test_exec_policy.cpp | 15 +++++++++++++--
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/src/adiar/exec_policy.h b/src/adiar/exec_policy.h
index ecdc10513..794d4dc55 100644
--- a/src/adiar/exec_policy.h
+++ b/src/adiar/exec_policy.h
@@ -126,12 +126,15 @@ namespace adiar
       //////////////////////////////////////////////////////////////////////////
       class transposition_growth
       {
+      private:
+        static constexpr float min_val = 0.0f;
+
       public:
         /// \brief Minimal value
         static constexpr transposition_growth
         min()
         {
-          return 0.0f;
+          return min_val;
         }
 
         /// \brief Maximal value
@@ -144,6 +147,14 @@ namespace adiar
       private:
         float _value;
 
+        /// \brief Convert into a `signed char`
+        static constexpr float
+        from_float(float f)
+        {
+          // Truncate `f` to be in the interval [0.0f, ...)
+          return f < min_val ? min_val : f;
+        }
+
       public:
         constexpr transposition_growth()
           : _value(1.5f)
@@ -151,7 +162,7 @@ namespace adiar
 
         /// \brief Wrap a `float`.
         constexpr transposition_growth(float value)
-          : _value(value)
+          : _value(from_float(value))
         {}
 
         /// \brief Reobtain the wrapped `float`
diff --git a/test/adiar/test_exec_policy.cpp b/test/adiar/test_exec_policy.cpp
index 7233495e1..ef5634ff0 100644
--- a/test/adiar/test_exec_policy.cpp
+++ b/test/adiar/test_exec_policy.cpp
@@ -16,14 +16,25 @@ go_bandit([]() {
           AssertThat(default__transposition_growth, Is().GreaterThanOrEqualTo(0.0f));
         });
 
-        it("'quantify::transposition max' defaults to a non-negative value", [&]() {
-          AssertThat(default__transposition_max, Is().GreaterThanOrEqualTo(0u));
+        it("'quantify::transposition growth' truncates negative values to '0.0f'", [&]() {
+          const exec_policy::quantify::transposition_growth res(-0.5f);
+          AssertThat(static_cast<float>(res), Is().GreaterThanOrEqualTo(0.0f));
         });
 
         it("'nested::fast reduce epsilon' defaults to a value in [-1,1]", [&]() {
           AssertThat(default__fast_reduce, Is().GreaterThanOrEqualTo(-1.0f));
           AssertThat(default__fast_reduce, Is().LessThanOrEqualTo(1.0f));
         });
+
+        it("'nested::fast reduce epsilon' truncates negative values to '-1.0f'", [&]() {
+          const exec_policy::nested::fast_reduce res(-42.0f);
+          AssertThat(static_cast<float>(res), Is().EqualTo(-1.0f));
+        });
+
+        it("'nested::fast reduce epsilon' truncates positive value to '1.0f'", [&]() {
+          const exec_policy::nested::fast_reduce res(2.0f);
+          AssertThat(static_cast<float>(res), Is().EqualTo(1.0f));
+        });
       });
 
       describe("exec_policy(const __ &)", [&]() {