perf!: Remove pop-from-empty guard

oboukli · Jan 18, 2025 · 423c5e1 · 423c5e1
1 parent 00b9fe0
commit 423c5e1
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Showing 4 changed files with 5 additions and 31 deletions.
diff --git a/include/forfun/container/forward_list.hpp b/include/forfun/container/forward_list.hpp
@@ -10,6 +10,7 @@
 #ifndef FORFUN_CONTAINER_FORWARD_LIST_HPP_
 #define FORFUN_CONTAINER_FORWARD_LIST_HPP_
 
+#include <cassert>
 #include <concepts>
 #include <utility>
 
@@ -59,12 +60,10 @@ class forward_list final {
         head_->next = aux;
     }
 
+    /// The behavior is undefined when popping the front of an empty container.
     auto pop_front() noexcept -> void
     {
-        if (head_ == nullptr)
-        {
-            return;
-        }
+        assert(head_ != nullptr);
 
         internal::forward_list_node<T>* const aux{head_};
         head_ = head_->next;

diff --git a/src/forfun/container/list.cpp b/src/forfun/container/list.cpp
@@ -54,16 +54,10 @@ auto list::push_back(list::value_type value) noexcept(false) -> void
     end_->previous_ = n;
 }
 
+/// The behavior is undefined when popping the back of an empty container.
 auto list::pop_back() noexcept -> void
 {
-    if (tail_ == end_) [[unlikely]]
-    {
-        assert(head_ == end_);
-        assert(size_ == size_type{});
-
-        return;
-    }
-
+    assert(tail_ != end_);
     assert(size_ > size_type{});
     assert(head_ != end_);
 

diff --git a/test/container/forward_list_test.cpp b/test/container/forward_list_test.cpp
@@ -91,15 +91,6 @@ TEST_CASE("Forward list", "[container][forward_list][dynamic_allocation]")
         REQUIRE_FALSE(forward_list.empty());
     }
 
-    SECTION("Pop back one element out of empty list")
-    {
-        forfun::experimental::container::forward_list<int> forward_list{};
-
-        forward_list.pop_front();
-
-        REQUIRE(forward_list.empty());
-    }
-
     SECTION("Pop back one element out of list of one element")
     {
         forfun::experimental::container::forward_list<int> forward_list{};

diff --git a/test/container/list_test.cpp b/test/container/list_test.cpp
@@ -151,16 +151,6 @@ TEST_CASE("Linked list", "[container][list][dynamic_allocation]")
         REQUIRE_FALSE(list.empty());
     }
 
-    SECTION("Pop back one element out of empty list")
-    {
-        forfun::experimental::container::list list{};
-
-        list.pop_back();
-
-        REQUIRE(list.empty());
-        REQUIRE(list.size() == std::size_t{0U});
-    }
-
     SECTION("Pop back one element out of list of one element")
     {
         forfun::experimental::container::list list{};