From 909b0fe0e79ce7d5ec78bc71d62b1b28b368b64d Mon Sep 17 00:00:00 2001
From: Valentin Shergin <shergin@fb.com>
Date: Thu, 12 Dec 2019 12:46:33 -0800
Subject: [PATCH] Fabric: `operator==` and `std::hash` for
 `AttributedStringBox`

Summary:
That will allow building a custom caching table for boxed stings to cache text measurements for them in TextLayoutManager.

Changelog: [Internal] Fabric-specific internal change.

Reviewed By: sammy-SC

Differential Revision: D18950428

fbshipit-source-id: 8ceef29543dc6ed540043e32d65f3295030ae90f
---
 .../attributedstring/AttributedStringBox.cpp  | 21 +++++++++++++++++++
 .../attributedstring/AttributedStringBox.h    | 18 ++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/ReactCommon/fabric/attributedstring/AttributedStringBox.cpp b/ReactCommon/fabric/attributedstring/AttributedStringBox.cpp
index d0846b7252d..5983a7fc754 100644
--- a/ReactCommon/fabric/attributedstring/AttributedStringBox.cpp
+++ b/ReactCommon/fabric/attributedstring/AttributedStringBox.cpp
@@ -40,5 +40,26 @@ std::shared_ptr<void> AttributedStringBox::getOpaquePointer() const {
   return opaquePointer_;
 }
 
+bool operator==(
+    AttributedStringBox const &lhs,
+    AttributedStringBox const &rhs) {
+  if (lhs.getMode() != rhs.getMode()) {
+    return false;
+  }
+
+  switch (lhs.getMode()) {
+    case facebook::react::AttributedStringBox::Mode::Value:
+      return lhs.getValue() == rhs.getValue();
+    case facebook::react::AttributedStringBox::Mode::OpaquePointer:
+      return lhs.getOpaquePointer() == rhs.getOpaquePointer();
+  }
+}
+
+bool operator!=(
+    AttributedStringBox const &lhs,
+    AttributedStringBox const &rhs) {
+  return !(lhs == rhs);
+}
+
 } // namespace react
 } // namespace facebook
diff --git a/ReactCommon/fabric/attributedstring/AttributedStringBox.h b/ReactCommon/fabric/attributedstring/AttributedStringBox.h
index ee8cf099223..8b7d4da1c59 100644
--- a/ReactCommon/fabric/attributedstring/AttributedStringBox.h
+++ b/ReactCommon/fabric/attributedstring/AttributedStringBox.h
@@ -58,5 +58,23 @@ class AttributedStringBox final {
   std::shared_ptr<void> opaquePointer_;
 };
 
+bool operator==(AttributedStringBox const &lhs, AttributedStringBox const &rhs);
+bool operator!=(AttributedStringBox const &lhs, AttributedStringBox const &rhs);
+
 } // namespace react
 } // namespace facebook
+
+template <>
+struct std::hash<facebook::react::AttributedStringBox> {
+  size_t operator()(
+      facebook::react::AttributedStringBox const &attributedStringBox) const {
+    switch (attributedStringBox.getMode()) {
+      case facebook::react::AttributedStringBox::Mode::Value:
+        return std::hash<facebook::react::AttributedString>()(
+            attributedStringBox.getValue());
+      case facebook::react::AttributedStringBox::Mode::OpaquePointer:
+        return std::hash<std::shared_ptr<void>>()(
+            attributedStringBox.getOpaquePointer());
+    }
+  }
+};