From 2b58494690aefb16e88e30f5ce01de5ed9ef5459 Mon Sep 17 00:00:00 2001
From: Brendan Asselstine <mail.asselstine@gmail.com>
Date: Tue, 15 Aug 2023 20:59:53 -0700
Subject: [PATCH] Only emit events when amounts non-zero

---
 src/TwabController.sol | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/src/TwabController.sol b/src/TwabController.sol
index 613b634..dd91d1c 100644
--- a/src/TwabController.sol
+++ b/src/TwabController.sol
@@ -657,7 +657,9 @@ contract TwabController {
     ) = TwabLib.increaseBalances(PERIOD_LENGTH, PERIOD_OFFSET, _account, _amount, _delegateAmount);
 
     // Always emit the balance change event
-    emit IncreasedBalance(_vault, _user, _amount, _delegateAmount);
+    if (_amount != 0 || _delegateAmount != 0) {
+      emit IncreasedBalance(_vault, _user, _amount, _delegateAmount);
+    }
 
     // Conditionally emit the observation recorded event
     if (_isObservationRecorded) {
@@ -700,7 +702,9 @@ contract TwabController {
       );
 
     // Always emit the balance change event
-    emit DecreasedBalance(_vault, _user, _amount, _delegateAmount);
+    if (_amount != 0 || _delegateAmount != 0) {
+      emit DecreasedBalance(_vault, _user, _amount, _delegateAmount);
+    }
 
     // Conditionally emit the observation recorded event
     if (_isObservationRecorded) {
@@ -742,7 +746,9 @@ contract TwabController {
       );
 
     // Always emit the balance change event
-    emit DecreasedTotalSupply(_vault, _amount, _delegateAmount);
+    if (_amount != 0 || _delegateAmount != 0) {
+      emit DecreasedTotalSupply(_vault, _amount, _delegateAmount);
+    }
 
     // Conditionally emit the observation recorded event
     if (_isObservationRecorded) {
@@ -776,7 +782,9 @@ contract TwabController {
     ) = TwabLib.increaseBalances(PERIOD_LENGTH, PERIOD_OFFSET, _account, _amount, _delegateAmount);
 
     // Always emit the balance change event
-    emit IncreasedTotalSupply(_vault, _amount, _delegateAmount);
+    if (_amount != 0 || _delegateAmount != 0) {
+      emit IncreasedTotalSupply(_vault, _amount, _delegateAmount);
+    }
 
     // Conditionally emit the observation recorded event
     if (_isObservationRecorded) {