From dc70a04100fd491151d3478a05ecf8baecfa894c Mon Sep 17 00:00:00 2001
From: Greg Ercolano <erco@seriss.com>
Date: Wed, 10 Jan 2024 21:32:02 -0800
Subject: [PATCH] Add Fl_String not-equal test

---
 src/Fl_String.H        |  1 +
 src/Fl_String.cxx      | 13 +++++++++++++
 test/unittest_core.cxx |  2 ++
 3 files changed, 16 insertions(+)

diff --git a/src/Fl_String.H b/src/Fl_String.H
index d10d75b6c..e7fbf49eb 100644
--- a/src/Fl_String.H
+++ b/src/Fl_String.H
@@ -135,6 +135,7 @@ public:
 FL_EXPORT Fl_String operator+(const Fl_String& lhs, const Fl_String& rhs);
 FL_EXPORT Fl_String operator+(const Fl_String& lhs, const char* rhs);
 FL_EXPORT bool operator==(const Fl_String & lhs, const Fl_String & rhs);
+FL_EXPORT bool operator!=(const Fl_String & lhs, const Fl_String & rhs);
 
 /**
 \}
diff --git a/src/Fl_String.cxx b/src/Fl_String.cxx
index 8fd8e5f51..60d50ef99 100644
--- a/src/Fl_String.cxx
+++ b/src/Fl_String.cxx
@@ -645,6 +645,19 @@ bool operator==(const Fl_String &lhs, const Fl_String &rhs) {
   return false;
 }
 
+/**
+ Compare two strings for inequality.
+ \param[in] lhs first string
+ \param[in] rhs second string
+ \return true if strings differ in size or content
+ */
+bool operator!=(const Fl_String &lhs, const Fl_String &rhs) {
+  if (lhs.size() != rhs.size()) return true;
+  int sz = lhs.size();  // same size for both
+  if (memcmp(lhs.data(), rhs.data(), sz) != 0) return true;
+  return false;
+}
+
 /**
 \}
 \endcond
diff --git a/test/unittest_core.cxx b/test/unittest_core.cxx
index 23e7ab953..bc91c8dd4 100644
--- a/test/unittest_core.cxx
+++ b/test/unittest_core.cxx
@@ -193,6 +193,8 @@ TEST(Fl_String, Non-Member Functions) {
   EXPECT_STREQ(result.c_str(), "x");
   EXPECT_TRUE(!(a == b));
   EXPECT_TRUE(a == a);
+  EXPECT_FALSE((a != a));              // neq -erco
+  EXPECT_TRUE((a != b));               // neq -erco
   EXPECT_TRUE(empty == empty);
   EXPECT_TRUE(a+b == "ab");
   EXPECT_TRUE(a+"b" == "a" + b);