From adaf511221e26305167936e6ebb22f50aa900439 Mon Sep 17 00:00:00 2001
From: Danil Chapovalov <danilchap@webrtc.org>
Date: Mon, 9 May 2022 16:01:25 +0200
Subject: [PATCH] Extend UnitBase multiplication to support size_t

Bug: None
Change-Id: I8dcb85cdb2819df54d4cb0cae59b77d7d629123a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/260941
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36828}
---
 api/units/time_delta_unittest.cc | 28 ++++++++++++++++++++--------
 rtc_base/units/unit_base.h       |  8 ++++++++
 2 files changed, 28 insertions(+), 8 deletions(-)

diff --git a/api/units/time_delta_unittest.cc b/api/units/time_delta_unittest.cc
index 3483d641bd..51a7aa233a 100644
--- a/api/units/time_delta_unittest.cc
+++ b/api/units/time_delta_unittest.cc
@@ -187,14 +187,6 @@ TEST(TimeDeltaTest, MathOperations) {
   EXPECT_EQ((delta_a + delta_b).ms(), kValueA + kValueB);
   EXPECT_EQ((delta_a - delta_b).ms(), kValueA - kValueB);
 
-  const int32_t kInt32Value = 123;
-  const double kFloatValue = 123.0;
-  EXPECT_EQ((TimeDelta::Micros(kValueA) * kValueB).us(), kValueA * kValueB);
-  EXPECT_EQ((TimeDelta::Micros(kValueA) * kInt32Value).us(),
-            kValueA * kInt32Value);
-  EXPECT_EQ((TimeDelta::Micros(kValueA) * kFloatValue).us(),
-            kValueA * kFloatValue);
-
   EXPECT_EQ((delta_b / 10).ms(), kValueB / 10);
   EXPECT_EQ(delta_b / delta_a, static_cast<double>(kValueB) / kValueA);
 
@@ -208,6 +200,26 @@ TEST(TimeDeltaTest, MathOperations) {
   EXPECT_EQ(mutable_delta, TimeDelta::Millis(kValueA));
 }
 
+TEST(TimeDeltaTest, MultiplyByScalar) {
+  const TimeDelta kValue = TimeDelta::Micros(267);
+  const int64_t kInt64 = 450;
+  const int32_t kInt32 = 123;
+  const size_t kUnsignedInt = 125;
+  const double kFloat = 123.0;
+
+  EXPECT_EQ((kValue * kInt64).us(), kValue.us() * kInt64);
+  EXPECT_EQ(kValue * kInt64, kInt64 * kValue);
+
+  EXPECT_EQ((kValue * kInt32).us(), kValue.us() * kInt32);
+  EXPECT_EQ(kValue * kInt32, kInt32 * kValue);
+
+  EXPECT_EQ((kValue * kUnsignedInt).us(), kValue.us() * int64_t{kUnsignedInt});
+  EXPECT_EQ(kValue * kUnsignedInt, kUnsignedInt * kValue);
+
+  EXPECT_DOUBLE_EQ((kValue * kFloat).us(), kValue.us() * kFloat);
+  EXPECT_EQ(kValue * kFloat, kFloat * kValue);
+}
+
 TEST(TimeDeltaTest, InfinityOperations) {
   const int64_t kValue = 267;
   const TimeDelta finite = TimeDelta::Millis(kValue);
diff --git a/rtc_base/units/unit_base.h b/rtc_base/units/unit_base.h
index 57cdd8c8b6..0cd6a61215 100644
--- a/rtc_base/units/unit_base.h
+++ b/rtc_base/units/unit_base.h
@@ -281,6 +281,9 @@ class RelativeUnit : public UnitBase<Unit_T> {
   constexpr Unit_T operator*(int32_t scalar) const {
     return UnitBase<Unit_T>::FromValue(this->ToValue() * scalar);
   }
+  constexpr Unit_T operator*(size_t scalar) const {
+    return UnitBase<Unit_T>::FromValue(this->ToValue() * scalar);
+  }
 
  protected:
   using UnitBase<Unit_T>::UnitBase;
@@ -298,6 +301,11 @@ template <class Unit_T>
 inline constexpr Unit_T operator*(int32_t scalar, RelativeUnit<Unit_T> other) {
   return other * scalar;
 }
+template <class Unit_T>
+inline constexpr Unit_T operator*(size_t scalar, RelativeUnit<Unit_T> other) {
+  return other * scalar;
+}
+
 template <class Unit_T>
 inline constexpr Unit_T operator-(RelativeUnit<Unit_T> other) {
   if (other.IsPlusInfinity())