Merge pull request #573 from totalgee/fix_erase_at_bounds

Fix  crash with out of bounds index (issue #572)

include/chaiscript/dispatchkit/bootstrap_stl.hpp

@@ -130,7 +130,7 @@ namespace chaiscript::bootstrap::standard_library {
       auto itr = container.begin();
       auto end = container.end();
 
-      if (pos < 0 || std::distance(itr, end) < (pos - 1)) {
+      if (pos < 0 || std::distance(itr, end) <= pos) {
         throw std::range_error("Cannot erase past end of range");
       }
 

unittests/vector_erase_at.chai

@@ -1,3 +1,24 @@
 auto x = [1, 2, 3]
 x.erase_at(1)
 assert_equal([1,3], x);
+
+try {
+  // We expect this to throw because of erasing an out of bounds index
+  x.erase_at(2)
+  assert_true(false)
+} catch (e) {
+  assert_true(true)
+}
+
+try {
+  // We expect this to throw because of erasing an out of bounds index
+  x.erase_at(-1)
+  assert_true(false)
+} catch (e) {
+  assert_true(true)
+}
+
+x.erase_at(0)
+assert_equal([3], x)
+x.erase_at(0)
+assert_equal([], x)

unittests/vector_insert_at.chai

@@ -1,3 +1,25 @@
 auto x = [1, 2, 3]
 x.insert_at(1, 6)
 assert_equal([1,6,2,3], x);
+
+try {
+  // We expect this to throw because of inserting an out of bounds index
+  x.insert_at(5, 55)
+  assert_true(false)
+} catch (e) {
+  assert_true(true)
+}
+
+// Inserting to the end should be allowed
+x.insert_at(4, 44)
+
+try {
+  // We expect this to throw because of inserting an out of bounds index
+  x.insert_at(-1, 111)
+  assert_true(false)
+} catch (e) {
+  assert_true(true)
+}
+
+x.insert_at(0, 100)
+assert_equal([100, 1, 6, 2, 3, 44], x)