intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 61 insertions, 0 deletions

diff --git a/library/cpp/iterator/ut/mapped_ut.cpp b/library/cpp/iterator/ut/mapped_ut.cpp
new file mode 100644
index 0000000000..440cd37945
--- /dev/null
+++ b/library/cpp/iterator/ut/mapped_ut.cpp
@@ -0,0 +1,61 @@
+#include <library/cpp/iterator/mapped.h>
+
+#include <library/cpp/testing/gtest/gtest.h>
+
+#include <util/generic/map.h>
+#include <util/generic/vector.h>
+
+using namespace testing;
+
+TEST(TIterator, TMappedIteratorTest) {
+    TVector<int> x = {1, 2, 3, 4, 5};
+    auto it = MakeMappedIterator(x.begin(), [](int x) { return x + 7; });
+
+    EXPECT_EQ(*it, 8);
+    EXPECT_EQ(it[2], 10);
+}
+
+TEST(TIterator, TMappedRangeTest) {
+    TVector<int> x = {1, 2, 3, 4, 5};
+
+    EXPECT_THAT(
+        MakeMappedRange(
+            x,
+            [](int x) { return x + 3; }
+        ),
+        ElementsAre(4, 5, 6, 7, 8)
+    );
+}
+
+//TODO: replace with dedicated IterateKeys / IterateValues methods
+TEST(TIterator, TMutableMappedRangeTest) {
+    TMap<int, int> points = {{1, 2}, {3, 4}};
+
+    EXPECT_THAT(
+        MakeMappedRange(
+            points.begin(), points.end(),
+            [](TMap<int, int>::value_type& kv) -> int& { return kv.second; }
+        ),
+        ElementsAre(2, 4)
+    );
+}
+
+TEST(TIterator, TOwningMappedMethodTest) {
+    auto range = MakeMappedRange(
+        TVector<std::pair<int, int>>{std::make_pair(1, 2), std::make_pair(3, 4)},
+        [](auto& point) -> int& {
+            return point.first;
+        }
+    );
+    EXPECT_EQ(range[0], 1);
+    range[0] += 1;
+    EXPECT_EQ(range[0], 2);
+    (*range.begin()) += 1;
+    EXPECT_EQ(range[0], 3);
+    for (int& y : range) {
+        y += 7;
+    }
+
+    EXPECT_EQ(*range.begin(), 10);
+    EXPECT_EQ(*(range.begin() + 1), 10);
+}