From 871629ffb362e6d002b0ed57a0aeb411b20a3a63 Mon Sep 17 00:00:00 2001
From: Martin Leitner-Ankerl <martin.ankerl@gmail.com>
Date: Mon, 11 Jul 2022 11:45:37 +0200
Subject: [PATCH] fix #8: erase() on empty map now works

---
 CMakeLists.txt                   | 2 +-
 include/ankerl/unordered_dense.h | 8 ++++++--
 meson.build                      | 2 +-
 test/unit/erase.cpp              | 6 ++++++
 4 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 236069f4..fd2eb37f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.12)
 project("unordered_dense"
-    VERSION 1.0.1
+    VERSION 1.0.2
     DESCRIPTION "A fast & densely stored hashmap and hashset based on robin-hood backward shift deletion"
     HOMEPAGE_URL "https://github.com/martinus/unordered_dense")
 
diff --git a/include/ankerl/unordered_dense.h b/include/ankerl/unordered_dense.h
index 52ec1765..7bc3f1cf 100644
--- a/include/ankerl/unordered_dense.h
+++ b/include/ankerl/unordered_dense.h
@@ -1,7 +1,7 @@
 ///////////////////////// ankerl::unordered_dense::{map, set} /////////////////////////
 
 // A fast & densely stored hashmap and hashset based on robin-hood backward shift deletion.
-// Version 1.0.1
+// Version 1.0.2
 // https://github.com/martinus/unordered_dense
 //
 // Licensed under the MIT License <http://opensource.org/licenses/MIT>.
@@ -32,7 +32,7 @@
 // see https://semver.org/spec/v2.0.0.html
 #define ANKERL_UNORDERED_DENSE_VERSION_MAJOR 1 // incompatible API changes
 #define ANKERL_UNORDERED_DENSE_VERSION_MINOR 0 // add functionality in a backwards compatible manner
-#define ANKERL_UNORDERED_DENSE_VERSION_PATCH 1 // backwards compatible bug fixes
+#define ANKERL_UNORDERED_DENSE_VERSION_PATCH 2 // backwards compatible bug fixes
 
 #include <algorithm>
 #include <array>
@@ -527,6 +527,10 @@ class table {
 
     template <typename K>
     auto do_erase_key(K&& key) -> size_t {
+        if (empty()) {
+            return 0;
+        }
+
         auto [dist_and_fingerprint, bucket] = next_while_less(key);
 
         while (dist_and_fingerprint == bucket->dist_and_fingerprint && !m_equal(key, get_key(m_values[bucket->value_idx]))) {
diff --git a/meson.build b/meson.build
index 9d3ebf71..3bb55346 100644
--- a/meson.build
+++ b/meson.build
@@ -18,7 +18,7 @@
 #
 
 project('unordered_dense', 'cpp',
-    version: '1.0.1',
+    version: '1.0.2',
     license: 'MIT',
     default_options : ['cpp_std=c++17', 'warning_level=3', 'werror=true'])
 
diff --git a/test/unit/erase.cpp b/test/unit/erase.cpp
index a93ce0f8..8be9806e 100644
--- a/test/unit/erase.cpp
+++ b/test/unit/erase.cpp
@@ -39,3 +39,9 @@ TEST_CASE("insert_erase_random") {
     us.erase(k);
     REQUIRE(is_eq(uds, us));
 }
+
+TEST_CASE("erase") {
+    auto map = ankerl::unordered_dense::map<int, int>();
+    REQUIRE(0 == map.erase(123));
+    REQUIRE(0 == map.count(0));
+}