code: добавлены тесты

unittest.cpp

@@ -0,0 +1,39 @@
+#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("Identical numbers") {
+    double min = 0, max = 0;
+    find_minmax({ 5, 5, 5 }, min, max);
+    CHECK(min == 5);
+    CHECK(max == 5);
+}
+TEST_CASE("Empty vector") {
+    double min = 42, max = 42;
+    find_minmax({}, min, max);
+    CHECK(min == 42);
+    CHECK(max == 42);
+}
+TEST_CASE("Single element") {
+    double min = 0, max = 0;
+    find_minmax({ 42 }, min, max);
+    CHECK(min == 42);
+    CHECK(max == 42);
+}
+
+TEST_CASE("Negative numbers") {
+    double min = 0, max = 0;
+    find_minmax({ -3, -1, -2 }, min, max);
+    CHECK(min == -3);
+    CHECK(max == -1);
+}
+