From 067cce1ac0fdda3888ac067939df24d173e4149b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?F=C3=A1bio=20Henriques?= <contact@fabiohenriques.dev>
Date: Thu, 26 Oct 2023 09:57:21 -0300
Subject: [PATCH 1/2] Address review comments

---
 src/libs/actions/PersonalDetails.ts | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/libs/actions/PersonalDetails.ts b/src/libs/actions/PersonalDetails.ts
index 6600945b8601..e2dbef071f9b 100644
--- a/src/libs/actions/PersonalDetails.ts
+++ b/src/libs/actions/PersonalDetails.ts
@@ -70,11 +70,17 @@ function getDisplayNameForTypingIndicator(userAccountIDOrLogin: string, defaultD
     // so Number(string) is NaN. Search for personalDetails by login to get the display name.
     if (Number.isNaN(accountID)) {
         const detailsByLogin = Object.entries(allPersonalDetails ?? {}).find(([, value]) => value?.login === userAccountIDOrLogin)?.[1];
-        return detailsByLogin?.displayName ?? userAccountIDOrLogin;
+
+        // It's possible for displayName to be empty string, so we must fallback to userAccountIDOrLogin.
+        // eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing
+        return detailsByLogin?.displayName || userAccountIDOrLogin;
     }
 
     const detailsByAccountID = allPersonalDetails?.[accountID];
-    return detailsByAccountID?.displayName ?? detailsByAccountID?.login ?? defaultDisplayName;
+
+    // It's possible for displayName to be empty string, so we must fallback to login or defaultDisplayName.
+    // eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing
+    return detailsByAccountID?.displayName || detailsByAccountID?.login || defaultDisplayName;
 }
 
 /**
@@ -83,7 +89,9 @@ function getDisplayNameForTypingIndicator(userAccountIDOrLogin: string, defaultD
  * so we return empty strings instead.
  */
 function extractFirstAndLastNameFromAvailableDetails({login, displayName, firstName, lastName}: PersonalDetails): FirstAndLastName {
-    if (firstName ?? lastName) {
+    // It's possible for firstName to be empty string, so we must consider lastName instead.
+    // eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing
+    if (firstName || lastName) {
         return {firstName: firstName ?? '', lastName: lastName ?? ''};
     }
     if (login && Str.removeSMSDomain(login) === displayName) {

From 58eb8f3e8d100cf88a3a866346b7a9f866e2a9fa Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?F=C3=A1bio=20Henriques?= <contact@fabiohenriques.dev>
Date: Fri, 27 Oct 2023 09:33:28 -0300
Subject: [PATCH 2/2] Improve comments

---
 src/libs/actions/PersonalDetails.ts | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/libs/actions/PersonalDetails.ts b/src/libs/actions/PersonalDetails.ts
index e2dbef071f9b..90a53a8de8df 100644
--- a/src/libs/actions/PersonalDetails.ts
+++ b/src/libs/actions/PersonalDetails.ts
@@ -55,6 +55,7 @@ function getDisplayName(login: string, personalDetail: Pick<PersonalDetails, 'fi
     const lastName = userDetails.lastName ?? '';
     const fullName = `${firstName} ${lastName}`.trim();
 
+    // It's possible for fullName to be empty string, so we must use "||" to fallback to userLogin.
     return fullName || userLogin;
 }
 
@@ -71,14 +72,14 @@ function getDisplayNameForTypingIndicator(userAccountIDOrLogin: string, defaultD
     if (Number.isNaN(accountID)) {
         const detailsByLogin = Object.entries(allPersonalDetails ?? {}).find(([, value]) => value?.login === userAccountIDOrLogin)?.[1];
 
-        // It's possible for displayName to be empty string, so we must fallback to userAccountIDOrLogin.
+        // It's possible for displayName to be empty string, so we must use "||" to fallback to userAccountIDOrLogin.
         // eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing
         return detailsByLogin?.displayName || userAccountIDOrLogin;
     }
 
     const detailsByAccountID = allPersonalDetails?.[accountID];
 
-    // It's possible for displayName to be empty string, so we must fallback to login or defaultDisplayName.
+    // It's possible for displayName to be empty string, so we must use "||" to fallback to login or defaultDisplayName.
     // eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing
     return detailsByAccountID?.displayName || detailsByAccountID?.login || defaultDisplayName;
 }
@@ -89,7 +90,7 @@ function getDisplayNameForTypingIndicator(userAccountIDOrLogin: string, defaultD
  * so we return empty strings instead.
  */
 function extractFirstAndLastNameFromAvailableDetails({login, displayName, firstName, lastName}: PersonalDetails): FirstAndLastName {
-    // It's possible for firstName to be empty string, so we must consider lastName instead.
+    // It's possible for firstName to be empty string, so we must use "||" to consider lastName instead.
     // eslint-disable-next-line @typescript-eslint/prefer-nullish-coalescing
     if (firstName || lastName) {
         return {firstName: firstName ?? '', lastName: lastName ?? ''};