Copied code from issue into test.

Author: 5cript

tests/float_overlap_tests.hpp

@@ -0,0 +1,73 @@
+#pragma once
+
+#include "test_utility.hpp"
+#include "../draw.hpp"
+
+class OverlapFindTests
+    : public ::testing::Test
+{
+public:
+    using types = IntervalTypes <double>;
+protected:
+    IntervalTypes <double>::tree_type tree;
+};
+
+TEST_F(OverlapFindTests, FloatOverlapTest)
+{
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-1.483529864195180e+00, -1.296053859335657e+00));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-1.308996938995747e+00, -1.127801743538376e+00));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-1.134464013796314e+00, -9.562870818388700e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-9.599310885968813e-01, -7.834918877708545e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-7.853981633974484e-01, -6.090750919515169e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-6.108652381980154e-01, -4.348738075675338e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-4.363323129985824e-01, -2.608478200480425e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-2.617993877991495e-01, -8.693606119038631e-02));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(-8.726646259971654e-02, 8.726646259971654e-02));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(8.693606119038631e-02, 2.617993877991493e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(2.608478200480422e-01, 4.363323129985823e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(4.348738075675337e-01, 6.108652381980154e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(6.090750919515169e-01, 7.853981633974484e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(7.834918877708545e-01, 9.599310885968813e-01));
+    tree.insert(lib_interval_tree::make_safe_interval<double>(9.562870818388700e-01, 1.134464013796314e+00)); //
+    tree.insert(lib_interval_tree::make_safe_interval<double>(1.127801743538376e+00, 1.308996938995747e+00)); //
+    tree.insert(lib_interval_tree::make_safe_interval<double>(1.296053859335657e+00, 1.483529864195180e+00)); //
+
+    double lat0 = 1.040893537045970;
+    double lat1 = 1.570796326794897;
+
+    std::vector <lib_interval_tree::interval<double>> vecOverlapsA;
+    lib_interval_tree::interval <double> intSource({lat0, lat1});
+    for (auto itTargetInterval : tree) 
+    {
+        if (itTargetInterval.overlaps(intSource)) 
+        {
+            vecOverlapsA.push_back(itTargetInterval);
+        }
+    }
+
+    std::vector <lib_interval_tree::interval<double>> vecOverlapsB;
+    tree.overlap_find_all
+    (
+        {lat0, lat1},
+        [&vecOverlapsB](lib_interval_tree::interval_tree_t<double>::iterator ittarget)
+        {
+            vecOverlapsB.push_back(*ittarget); 
+            return true;
+        },
+        false
+    );
+
+    for (auto const& i : vecOverlapsA)
+    {
+        std::cout << i.low() << ", " << i.high() << "\n";
+    }
+    std::cout << "\n";
+    for (auto const& i : vecOverlapsB)
+    {
+        std::cout << i.low() << ", " << i.high() << "\n";
+    }
+
+    lib_interval_tree::drawTree("here.png", tree);
+    
+    ASSERT_EQ(vecOverlapsA, vecOverlapsB);
+}