From 1edbfdef6588b0e81b4c545031ce0bb2e104534b Mon Sep 17 00:00:00 2001
From: Andreas Pehrson <apehrson@mozilla.com>
Date: Thu, 27 Aug 2026 07:57:19 +0000
Subject: [PATCH] Bug 2051711 - Add operator<=> to nsTStringRepr.
 r=xpcom-reviewers,webrtc-reviewers,bwc,emilio

Differential Revision: https://phabricator.services.mozilla.com/D309690
---
 .../gtest/peer_connection_unittest.cpp        |  4 +--
 xpcom/string/nsTStringRepr.h                  | 25 +++----------------
 xpcom/tests/gtest/TestStrings.cpp             | 19 ++++++++++++++
 3 files changed, 24 insertions(+), 24 deletions(-)

diff --git a/media/webrtc/signaling/gtest/peer_connection_unittest.cpp b/media/webrtc/signaling/gtest/peer_connection_unittest.cpp
index 5d30fc5762e2..ef5722938382 100644
--- a/media/webrtc/signaling/gtest/peer_connection_unittest.cpp
+++ b/media/webrtc/signaling/gtest/peer_connection_unittest.cpp
@@ -13,9 +13,7 @@ namespace mozilla {
 
 static std::strong_ordering RtpExtensionHeaderUriComparator(
     const PeerConnectionImpl::RtpExtensionHeader& aHeader, const char* aUri) {
-  // TODO bug 2051711: use nsCString::operator<=> directly.
-  return std::string_view(aHeader.extensionname.get()) <=>
-         std::string_view(aUri);
+  return aHeader.extensionname <=> nsDependentCString(aUri);
 }
 
 static const PeerConnectionImpl::RtpExtensionHeader* FindExtension(
diff --git a/xpcom/string/nsTStringRepr.h b/xpcom/string/nsTStringRepr.h
index fb1a822dc92f..8eb1d2ab0f1a 100644
--- a/xpcom/string/nsTStringRepr.h
+++ b/xpcom/string/nsTStringRepr.h
@@ -525,18 +525,6 @@ inline constexpr bool operator!=(const mozilla::detail::nsTStringRepr<T>& aLhs,
   return !aLhs.Equals(aRhs);
 }
 
-template <typename T>
-inline bool operator<(const mozilla::detail::nsTStringRepr<T>& aLhs,
-                      const mozilla::detail::nsTStringRepr<T>& aRhs) {
-  return Compare(aLhs, aRhs) < 0;
-}
-
-template <typename T>
-inline bool operator<=(const mozilla::detail::nsTStringRepr<T>& aLhs,
-                       const mozilla::detail::nsTStringRepr<T>& aRhs) {
-  return Compare(aLhs, aRhs) <= 0;
-}
-
 template <typename T>
 inline bool operator==(const mozilla::detail::nsTStringRepr<T>& aLhs,
                        const mozilla::detail::nsTStringRepr<T>& aRhs) {
@@ -550,15 +538,10 @@ inline bool operator==(const mozilla::detail::nsTStringRepr<T>& aLhs,
 }
 
 template <typename T>
-inline bool operator>=(const mozilla::detail::nsTStringRepr<T>& aLhs,
-                       const mozilla::detail::nsTStringRepr<T>& aRhs) {
-  return Compare(aLhs, aRhs) >= 0;
-}
-
-template <typename T>
-inline bool operator>(const mozilla::detail::nsTStringRepr<T>& aLhs,
-                      const mozilla::detail::nsTStringRepr<T>& aRhs) {
-  return Compare(aLhs, aRhs) > 0;
+inline std::strong_ordering operator<=>(
+    const mozilla::detail::nsTStringRepr<T>& aLhs,
+    const mozilla::detail::nsTStringRepr<T>& aRhs) {
+  return Compare(aLhs, aRhs) <=> 0;
 }
 
 template <typename Char>
diff --git a/xpcom/tests/gtest/TestStrings.cpp b/xpcom/tests/gtest/TestStrings.cpp
index 86d0baf7bbfc..05ea9909c0da 100644
--- a/xpcom/tests/gtest/TestStrings.cpp
+++ b/xpcom/tests/gtest/TestStrings.cpp
@@ -2415,6 +2415,25 @@ TEST_F(Strings, printf) {
 #undef verify_printf_strings
 #undef create_printf_strings
 
+TEST(String, SpaceshipCompare)
+{
+  nsAutoCString a("A");
+  nsCString b("B");
+  EXPECT_EQ(a <=> a, std::strong_ordering::equal);
+  EXPECT_EQ(a <=> b, std::strong_ordering::less);
+  EXPECT_EQ(b <=> a, std::strong_ordering::greater);
+  EXPECT_EQ(b <=> b, std::strong_ordering::equal);
+
+  nsLiteralCString ab = "AB"_ns;
+  EXPECT_EQ(a <=> ab, std::strong_ordering::less);
+  EXPECT_EQ(b <=> ab, std::strong_ordering::greater);
+
+  a.Append("B");
+  EXPECT_EQ(a <=> a, std::strong_ordering::equal);
+  EXPECT_EQ(a <=> b, std::strong_ordering::less);
+  EXPECT_EQ(a <=> ab, std::strong_ordering::equal);
+}
+
 // Note the five calls in the loop, so divide by 100k
 MOZ_GTEST_BENCH_F(Strings, PerfStripWhitespace, [this] {
   nsCString test1(mExample1Utf8);