build: new doctest

labor01.sln

@@ -5,6 +5,8 @@ VisualStudioVersion = 17.7.34024.191
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "labor01", "labor01.vcxproj", "{BB0D0896-4CC7-4B1C-9B61-0D3FE77C22CA}"
 EndProject
+Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "unittest", "unittest.vcxproj", "{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|x64 = Debug|x64
@@ -21,6 +23,14 @@ Global
 		{BB0D0896-4CC7-4B1C-9B61-0D3FE77C22CA}.Release|x64.Build.0 = Release|x64
 		{BB0D0896-4CC7-4B1C-9B61-0D3FE77C22CA}.Release|x86.ActiveCfg = Release|Win32
 		{BB0D0896-4CC7-4B1C-9B61-0D3FE77C22CA}.Release|x86.Build.0 = Release|Win32
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Debug|x64.ActiveCfg = Debug|x64
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Debug|x64.Build.0 = Debug|x64
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Debug|x86.ActiveCfg = Debug|Win32
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Debug|x86.Build.0 = Debug|Win32
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Release|x64.ActiveCfg = Release|x64
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Release|x64.Build.0 = Release|x64
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Release|x86.ActiveCfg = Release|Win32
+		{9AD59A50-DBD4-43A6-9E29-FCE8AB4DCC54}.Release|x86.Build.0 = Release|Win32
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

unittest.cpp

@@ -0,0 +1,37 @@
+#define DOCTEST_CONFIG_NO_MULTITHREADING
+#define DOCTEST_CONFIG_IMPLEMENT_WITH_MAIN
+#include "doctest.h"
+#include "histogram_internal.h"
+
+TEST_CASE("distinct positive numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({ 1, 2 }, min, max);
+    CHECK(min == 1);
+    CHECK(max == 2);
+}
+
+TEST_CASE("negative numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({ -10, 10 }, min, max);
+    CHECK(min == -10);
+    CHECK(max == 10);
+}
+
+TEST_CASE("empty numbers") {
+    double min = 0;
+    double max = 0;
+    find_minmax({ }, min, max);
+    CHECK(min != 0);
+    CHECK(max != 0);
+}
+
+TEST_CASE("one number") {
+    double min = 0;
+    double max = 0;
+    find_minmax({ 2 }, min, max);
+    CHECK(min == 2);
+    CHECK(max == 2);
+}
+