diff -r 96fa7fa6af4f -r 0f3c9662f9b5 test/test_string.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/test_string.cpp	Fri Sep 09 20:19:08 2022 +0200
@@ -0,0 +1,531 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 2021 Mike Becker, Olaf Wintermann All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *   1. Redistributions of source code must retain the above copyright
+ *      notice, this list of conditions and the following disclaimer.
+ *
+ *   2. Redistributions in binary form must reproduce the above copyright
+ *      notice, this list of conditions and the following disclaimer in the
+ *      documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "cx/string.h"
+#include "util_allocator.h"
+
+#include <gtest/gtest.h>
+
+TEST(String, construct) {
+    cxstring s1 = cx_str("1234");
+    cxstring s2 = cx_strn("abcd", 2);
+    cxmutstr s3 = cx_mutstr((char *) "1234");
+    cxmutstr s4 = cx_mutstrn((char *) "abcd", 2);
+
+    EXPECT_EQ(s1.length, 4);
+    EXPECT_EQ(s2.length, 2);
+    EXPECT_EQ(s3.length, 4);
+    EXPECT_EQ(s4.length, 2);
+}
+
+TEST(String, strfree) {
+    CxTestingAllocator alloc;
+    auto test = (char *) cxMalloc(&alloc, 16);
+    cxmutstr str = cx_mutstrn(test, 16);
+    ASSERT_EQ(str.ptr, test);
+    EXPECT_EQ(str.length, 16);
+    cx_strfree_a(&alloc, &str);
+    EXPECT_EQ(str.ptr, nullptr);
+    EXPECT_EQ(str.length, 0);
+    EXPECT_TRUE(alloc.verify());
+}
+
+TEST(String, strlen) {
+    cxstring s1 = CX_STR("1234");
+    cxstring s2 = CX_STR(".:.:.");
+    cxstring s3 = CX_STR("X");
+
+    size_t len0 = cx_strlen(0);
+    size_t len1 = cx_strlen(1, s1);
+    size_t len2 = cx_strlen(2, s1, s2);
+    size_t len3 = cx_strlen(3, s1, s2, s3);
+
+    EXPECT_EQ(len0, 0);
+    EXPECT_EQ(len1, 4);
+    EXPECT_EQ(len2, 9);
+    EXPECT_EQ(len3, 10);
+}
+
+
+TEST(String, strchr) {
+    cxstring str = CX_STR("I will find you - and I will kill you");
+
+    cxstring notfound = cx_strchr(str, 'x');
+    EXPECT_EQ(notfound.length, 0);
+
+    cxstring result = cx_strchr(str, 'w');
+    EXPECT_EQ(result.length, 35);
+    EXPECT_EQ(strcmp("will find you - and I will kill you", result.ptr), 0);
+}
+
+TEST(String, strrchr) {
+    cxstring str = CX_STR("I will find you - and I will kill you");
+
+    cxstring notfound = cx_strrchr(str, 'x');
+    EXPECT_EQ(notfound.length, 0);
+
+    cxstring result = cx_strrchr(str, 'w');
+    EXPECT_EQ(result.length, 13);
+    EXPECT_EQ(strcmp("will kill you", result.ptr), 0);
+}
+
+TEST(String, strstr) {
+    cxstring str = CX_STR("find the match in this string");
+    cxstring longstr = CX_STR(
+            "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijkl"
+            "mnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwx"
+            "yzabcdeababababnopqrstuvwxyzabcdefghijklmnopqrstuvwxyzabcdefghij"
+            "klmnopqrstuvwxyzaababababababababrstuvwxyzabcdefghijklmnopqrstuv"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "wxyz1234567890");
+    cxstring longstrpattern = CX_STR(
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+    );
+    cxstring longstrresult = CX_STR(
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "abababababababababababababababababababababababababababababababab"
+            "wxyz1234567890"
+    );
+
+    cxstring notfound = cx_strstr(str, cx_str("no match"));
+    EXPECT_EQ(notfound.length, 0);
+
+    cxstring result = cx_strstr(str, cx_str("match"));
+    EXPECT_EQ(result.length, 20);
+    EXPECT_EQ(strcmp("match in this string", result.ptr), 0);
+
+    result = cx_strstr(str, cx_str(""));
+    EXPECT_EQ(result.length, str.length);
+    EXPECT_EQ(strcmp(str.ptr, result.ptr), 0);
+
+    result = cx_strstr(longstr, longstrpattern);
+    EXPECT_EQ(result.length, longstrresult.length);
+    EXPECT_EQ(strcmp(result.ptr, longstrresult.ptr), 0);
+}
+
+TEST(String, strcmp) {
+    cxstring str = CX_STR("compare this");
+
+    EXPECT_EQ(cx_strcmp(CX_STR(""), CX_STR("")), 0);
+    EXPECT_GT(cx_strcmp(str, CX_STR("")), 0);
+    EXPECT_EQ(cx_strcmp(str, CX_STR("compare this")), 0);
+    EXPECT_NE(cx_strcmp(str, CX_STR("Compare This")), 0);
+    EXPECT_LT(cx_strcmp(str, CX_STR("compare tool")), 0);
+    EXPECT_GT(cx_strcmp(str, CX_STR("compare shit")), 0);
+    EXPECT_LT(cx_strcmp(str, CX_STR("compare this not")), 0);
+    EXPECT_GT(cx_strcmp(str, CX_STR("compare")), 0);
+}
+
+TEST(String, strcasecmp) {
+    cxstring str = CX_STR("compare this");
+
+    EXPECT_EQ(cx_strcasecmp(CX_STR(""), CX_STR("")), 0);
+    EXPECT_GT(cx_strcasecmp(str, CX_STR("")), 0);
+    EXPECT_EQ(cx_strcasecmp(str, CX_STR("compare this")), 0);
+    EXPECT_EQ(cx_strcasecmp(str, CX_STR("Compare This")), 0);
+    EXPECT_LT(cx_strcasecmp(str, CX_STR("compare tool")), 0);
+    EXPECT_GT(cx_strcasecmp(str, CX_STR("compare shit")), 0);
+    EXPECT_LT(cx_strcasecmp(str, CX_STR("compare this not")), 0);
+    EXPECT_GT(cx_strcasecmp(str, CX_STR("compare")), 0);
+}
+
+
+TEST(String, strcat) {
+    cxstring s1 = CX_STR("12");
+    cxstring s2 = CX_STR("34");
+    cxstring s3 = CX_STR("56");
+    cxstring sn = {nullptr, 0};
+
+    CxTestingAllocator alloc;
+
+    cxmutstr t1 = cx_strcat_a(&alloc, 2, s1, s2);
+    EXPECT_EQ(cx_strcmp(cx_strcast(t1), CX_STR("1234")), 0);
+    cx_strfree_a(&alloc, &t1);
+
+    cxmutstr t2 = cx_strcat_a(&alloc, 3, s1, s2, s3);
+    EXPECT_EQ(cx_strcmp(cx_strcast(t2), CX_STR("123456")), 0);
+    cx_strfree_a(&alloc, &t2);
+
+    cxmutstr t3 = cx_strcat_a(&alloc, 6, s1, sn, s2, sn, s3, sn);
+    EXPECT_EQ(cx_strcmp(cx_strcast(t3), CX_STR("123456")), 0);
+    cx_strfree_a(&alloc, &t3);
+
+    cxmutstr t4 = cx_strcat_a(&alloc, 2, sn, sn);
+    EXPECT_EQ(cx_strcmp(cx_strcast(t4), CX_STR("")), 0);
+    cx_strfree_a(&alloc, &t4);
+
+    EXPECT_TRUE(alloc.verify());
+}
+
+TEST(String, strsplit) {
+
+    cxstring test = cx_str("this,is,a,csv,string");
+    size_t capa = 8;
+    cxstring list[8];
+    size_t n;
+
+    /* special case: empty string */
+    n = cx_strsplit(test, cx_str(""), capa, list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+
+    /* no delimiter occurrence */
+    n = cx_strsplit(test, cx_str("z"), capa, list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+
+    /* partially matching delimiter */
+    n = cx_strsplit(test, cx_str("is,not"), capa, list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+
+    /* matching single-char delimiter */
+    n = cx_strsplit(test, cx_str(","), capa, list);
+    ASSERT_EQ(n, 5);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("this")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("is")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("a")), 0);
+    EXPECT_EQ(cx_strcmp(list[3], cx_str("csv")), 0);
+    EXPECT_EQ(cx_strcmp(list[4], cx_str("string")), 0);
+
+    /* matching multi-char delimiter */
+    n = cx_strsplit(test, cx_str("is"), capa, list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("th")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str(",")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str(",a,csv,string")), 0);
+
+    /* bounded list using single-char delimiter */
+    n = cx_strsplit(test, cx_str(","), 3, list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("this")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("is")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("a,csv,string")), 0);
+
+    /* bounded list using multi-char delimiter */
+    n = cx_strsplit(test, cx_str("is"), 2, list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("th")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str(",is,a,csv,string")), 0);
+
+    /* start with delimiter */
+    n = cx_strsplit(test, cx_str("this"), capa, list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str(",is,a,csv,string")), 0);
+
+    /* end with delimiter */
+    n = cx_strsplit(test, cx_str("string"), capa, list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("this,is,a,csv,")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("")), 0);
+
+
+    /* end with delimiter exceed bound */
+    n = cx_strsplit(cx_str("a,b,c,"), cx_str(","), 3, list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("a")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("b")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("c,")), 0);
+
+    /* exact match */
+    n = cx_strsplit(test, cx_str("this,is,a,csv,string"), capa, list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("")), 0);
+
+    /* string to be split is only substring */
+    n = cx_strsplit(test, cx_str("this,is,a,csv,string,with,extension"), capa, list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+
+    /* subsequent encounter of delimiter (the string between is empty) */
+    n = cx_strsplit(test, cx_str("is,"), capa, list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("th")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("a,csv,string")), 0);
+}
+
+TEST(String, strsplit_a) {
+    CxTestingAllocator alloc;
+
+    cxstring test = cx_str("this,is,a,csv,string");
+    size_t capa = 8;
+    cxstring *list;
+    size_t n;
+
+    /* special case: empty string */
+    n = cx_strsplit_a(&alloc, test, cx_str(""), capa, &list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+    cxFree(&alloc, list);
+
+    /* no delimiter occurrence */
+    n = cx_strsplit_a(&alloc, test, cx_str("z"), capa, &list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+    cxFree(&alloc, list);
+
+    /* partially matching delimiter */
+    n = cx_strsplit_a(&alloc, test, cx_str("is,not"), capa, &list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+    cxFree(&alloc, list);
+
+    /* matching single-char delimiter */
+    n = cx_strsplit_a(&alloc, test, cx_str(","), capa, &list);
+    ASSERT_EQ(n, 5);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("this")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("is")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("a")), 0);
+    EXPECT_EQ(cx_strcmp(list[3], cx_str("csv")), 0);
+    EXPECT_EQ(cx_strcmp(list[4], cx_str("string")), 0);
+    cxFree(&alloc, list);
+
+    /* matching multi-char delimiter */
+    n = cx_strsplit_a(&alloc, test, cx_str("is"), capa, &list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("th")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str(",")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str(",a,csv,string")), 0);
+    cxFree(&alloc, list);
+
+    /* bounded list using single-char delimiter */
+    n = cx_strsplit_a(&alloc, test, cx_str(","), 3, &list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("this")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("is")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("a,csv,string")), 0);
+    cxFree(&alloc, list);
+
+    /* bounded list using multi-char delimiter */
+    n = cx_strsplit_a(&alloc, test, cx_str("is"), 2, &list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("th")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str(",is,a,csv,string")), 0);
+    cxFree(&alloc, list);
+
+    /* start with delimiter */
+    n = cx_strsplit_a(&alloc, test, cx_str("this"), capa, &list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str(",is,a,csv,string")), 0);
+    cxFree(&alloc, list);
+
+    /* end with delimiter */
+    n = cx_strsplit_a(&alloc, test, cx_str("string"), capa, &list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("this,is,a,csv,")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("")), 0);
+    cxFree(&alloc, list);
+
+    /* end with delimiter exceed bound */
+    n = cx_strsplit_a(&alloc, cx_str("a,b,c,"), cx_str(","), 3, &list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("a")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("b")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("c,")), 0);
+    cxFree(&alloc, list);
+
+    /* exact match */
+    n = cx_strsplit_a(&alloc, test, cx_str("this,is,a,csv,string"), capa, &list);
+    ASSERT_EQ(n, 2);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("")), 0);
+    cxFree(&alloc, list);
+
+    /* string to be split is only substring */
+    n = cx_strsplit_a(&alloc, test, cx_str("this,is,a,csv,string,with,extension"), capa, &list);
+    ASSERT_EQ(n, 1);
+    EXPECT_EQ(cx_strcmp(list[0], test), 0);
+    cxFree(&alloc, list);
+
+    /* subsequent encounter of delimiter (the string between is empty) */
+    n = cx_strsplit_a(&alloc, test, cx_str("is,"), capa, &list);
+    ASSERT_EQ(n, 3);
+    EXPECT_EQ(cx_strcmp(list[0], cx_str("th")), 0);
+    EXPECT_EQ(cx_strcmp(list[1], cx_str("")), 0);
+    EXPECT_EQ(cx_strcmp(list[2], cx_str("a,csv,string")), 0);
+    cxFree(&alloc, list);
+
+    EXPECT_TRUE(alloc.verify());
+}
+
+TEST(String, strtrim) {
+    cxstring t1 = cx_strtrim(cx_str("  ein test  \t "));
+    cxstring t2 = cx_strtrim(cx_str("abc"));
+    cxstring t3 = cx_strtrim(cx_str(" 123"));
+    cxstring t4 = cx_strtrim(cx_str("xyz "));
+    cxstring t5 = cx_strtrim(cx_str("   "));
+    cxstring empty = cx_strtrim(cx_str(""));
+
+    EXPECT_EQ(cx_strcmp(t1, cx_str("ein test")), 0);
+    EXPECT_EQ(cx_strcmp(t2, cx_str("abc")), 0);
+    EXPECT_EQ(cx_strcmp(t3, cx_str("123")), 0);
+    EXPECT_EQ(cx_strcmp(t4, cx_str("xyz")), 0);
+    EXPECT_EQ(cx_strcmp(t5, cx_str("")), 0);
+    EXPECT_EQ(cx_strcmp(empty, cx_str("")), 0);
+}
+
+TEST(String, strprefix) {
+    cxstring str = CX_STR("test my prefix and my suffix");
+    cxstring empty = CX_STR("");
+    EXPECT_FALSE(cx_strprefix(empty, cx_str("pref")));
+    EXPECT_TRUE(cx_strprefix(str, empty));
+    EXPECT_TRUE(cx_strprefix(empty, empty));
+    EXPECT_TRUE(cx_strprefix(str, cx_str("test ")));
+    EXPECT_FALSE(cx_strprefix(str, cx_str("8-) fsck ")));
+}
+
+TEST(String, strsuffix) {
+    cxstring str = CX_STR("test my prefix and my suffix");
+    cxstring empty = CX_STR("");
+    EXPECT_FALSE(cx_strsuffix(empty, cx_str("suf")));
+    EXPECT_TRUE(cx_strsuffix(str, empty));
+    EXPECT_TRUE(cx_strsuffix(empty, empty));
+    EXPECT_TRUE(cx_strsuffix(str, cx_str("fix")));
+    EXPECT_FALSE(cx_strsuffix(str, cx_str("fox")));
+}
+
+TEST(String, strcaseprefix) {
+    cxstring str = CX_STR("test my prefix and my suffix");
+    cxstring empty = CX_STR("");
+    EXPECT_FALSE(cx_strcaseprefix(empty, cx_str("pREf")));
+    EXPECT_TRUE(cx_strcaseprefix(str, empty));
+    EXPECT_TRUE(cx_strcaseprefix(empty, empty));
+    EXPECT_TRUE(cx_strcaseprefix(str, cx_str("TEST ")));
+    EXPECT_FALSE(cx_strcaseprefix(str, cx_str("8-) fsck ")));
+}
+
+TEST(String, strcasesuffix) {
+    cxstring str = CX_STR("test my prefix and my suffix");
+    cxstring empty = CX_STR("");
+    EXPECT_FALSE(cx_strcasesuffix(empty, cx_str("sUf")));
+    EXPECT_TRUE(cx_strcasesuffix(str, empty));
+    EXPECT_TRUE(cx_strcasesuffix(empty, empty));
+    EXPECT_TRUE(cx_strcasesuffix(str, cx_str("FIX")));
+    EXPECT_FALSE(cx_strcasesuffix(str, cx_str("fox")));
+}
+
+TEST(String, strreplace) {
+    cxstring str = CX_STR("test ababab string aba");
+    cxstring longstr = CX_STR(
+            "xyaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaacd");
+    cxstring notrail = CX_STR("test abab");
+    cxstring empty = CX_STR("");
+    cxstring astr = CX_STR("aaaaaaaaaa");
+    cxstring csstr = CX_STR("test AB ab TEST xyz");
+
+    cxmutstr repl = cx_strreplace(str, cx_str("abab"), cx_str("muchlonger"));
+    cxstring expected = CX_STR("test muchlongerab string aba");
+
+    cxmutstr repln = cx_strreplacen(str, cx_str("ab"), cx_str("c"), 2);
+    cxstring expectedn = CX_STR("test ccab string aba");
+
+    cxmutstr longrepl = cx_strreplace(longstr, cx_str("a"), cx_str("z"));
+    cxstring longexpect = CX_STR(
+            "xyzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzcd");
+
+    cxmutstr replnotrail = cx_strreplace(notrail, cx_str("ab"), cx_str("z"));
+    cxstring notrailexpect = CX_STR("test zz");
+
+    cxmutstr repleq = cx_strreplace(str, str, cx_str("hello"));
+    cxstring eqexpect = CX_STR("hello");
+
+    cxmutstr replempty1 = cx_strreplace(empty, cx_str("ab"), cx_str("c")); // expect: empty
+    cxmutstr replempty2 = cx_strreplace(str, cx_str("abab"), empty);
+    cxstring emptyexpect2 = CX_STR("test ab string aba");
+
+    cxmutstr replpre = cx_strreplace(str, cx_str("test "), cx_str("TEST "));
+    cxstring preexpected = CX_STR("TEST ababab string aba");
+
+    cxmutstr replan1 = cx_strreplacen(astr, cx_str("a"), cx_str("x"), 1);
+    cxstring an1expected = CX_STR("xaaaaaaaaa");
+
+    cxmutstr replan4 = cx_strreplacen(astr, cx_str("a"), cx_str("x"), 4);
+    cxstring an4expected = CX_STR("xxxxaaaaaa");
+
+    cxmutstr replan9 = cx_strreplacen(astr, cx_str("a"), cx_str("x"), 9);
+    cxstring an9expected = CX_STR("xxxxxxxxxa");
+
+    cxmutstr replan10 = cx_strreplacen(astr, cx_str("a"), cx_str("x"), 10);
+    cxstring an10expected = CX_STR("xxxxxxxxxx");
+
+    cxmutstr replcs1 = cx_strreplace(csstr, cx_str("AB"), cx_str("*"));
+    cxstring cs1expected = CX_STR("test * ab TEST xyz");
+
+    cxmutstr replcs2 = cx_strreplace(csstr, cx_str("test"), cx_str("TEST"));
+    cxstring cs2expected = CX_STR("TEST AB ab TEST xyz");
+
+
+    EXPECT_NE(repl.ptr, str.ptr);
+    EXPECT_EQ(cx_strcmp(cx_strcast(repl), expected), 0);
+    EXPECT_NE(repln.ptr, str.ptr);
+    EXPECT_EQ(cx_strcmp(cx_strcast(repln), expectedn), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(longrepl), longexpect), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replnotrail), notrailexpect), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(repleq), eqexpect), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replempty1), empty), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replempty2), emptyexpect2), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replpre), preexpected), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replan1), an1expected), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replan4), an4expected), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replan9), an9expected), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replan10), an10expected), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replcs1), cs1expected), 0);
+    EXPECT_EQ(cx_strcmp(cx_strcast(replcs2), cs2expected), 0);
+
+    cx_strfree(&repl);
+    cx_strfree(&repln);
+    cx_strfree(&longrepl);
+    cx_strfree(&replnotrail);
+    cx_strfree(&repleq);
+    cx_strfree(&replempty1);
+    cx_strfree(&replempty2);
+    cx_strfree(&replpre);
+    cx_strfree(&replan1);
+    cx_strfree(&replan4);
+    cx_strfree(&replan9);
+    cx_strfree(&replan10);
+    cx_strfree(&replcs1);
+    cx_strfree(&replcs2);
+}