single_relative_member_infos.patch

diff --git a/lib/selectors/user-selectors.js b/lib/selectors/user-selectors.js
index 1f5e9dfe97..280cf60de5 100644
--- a/lib/selectors/user-selectors.js
+++ b/lib/selectors/user-selectors.js
@@ -58,92 +58,63 @@ function userIDsToRelativeUserInfos(
   return relativeUserInfos;
 }
 
-function getMinimallyEncodedRelativeMemberInfos(
-  threadInfo: ?MinimallyEncodedRawThreadInfo,
-  currentUserID: ?string,
-  userInfos: UserInfos,
-): $ReadOnlyArray<MinimallyEncodedRelativeMemberInfo> {
-  const relativeMemberInfos = [];
-  if (!threadInfo) {
-    return relativeMemberInfos;
-  }
-  const memberInfos = threadInfo.members;
-  for (const memberInfo of memberInfos) {
-    if (!memberInfo.role) {
-      continue;
-    }
-    const username = userInfos[memberInfo.id]
-      ? userInfos[memberInfo.id].username
-      : null;
-    if (memberInfo.id === currentUserID) {
-      relativeMemberInfos.unshift({
-        ...memberInfo,
-        username,
-        isViewer: true,
-      });
-    } else {
-      relativeMemberInfos.push({
-        ...memberInfo,
-        username,
-        isViewer: false,
-      });
-    }
-  }
-  return relativeMemberInfos;
-}
+type ExtractArrayParam = <T>(arr: $ReadOnlyArray<T>) => T;
 
-function getLegacyRelativeMemberInfos(
-  threadInfo: ?LegacyRawThreadInfo,
+function getRelativeMemberInfos<
+  TI: MinimallyEncodedRawThreadInfo | LegacyRawThreadInfo,
+>(
+  threadInfo: ?TI,
   currentUserID: ?string,
   userInfos: UserInfos,
-): $ReadOnlyArray<LegacyRelativeMemberInfo> {
-  const relativeMemberInfos = [];
+): $ReadOnlyArray<$ReadOnly<{
+  ...$Call<
+    ExtractArrayParam,
+    $PropertyType<TI, 'members'>,
+  >,
+  +username: ?string,
+  +isViewer: boolean,
+}>> {
+  const relativeMemberInfos: Array<$ReadOnly<{
+    ...$Call<
+      ExtractArrayParam,
+      $PropertyType<TI, 'members'>,
+    >,
+    +username: ?string,
+    +isViewer: boolean,
+  }>> = [];
   if (!threadInfo) {
     return relativeMemberInfos;
   }
   const memberInfos = threadInfo.members;
-  for (const memberInfo of memberInfos) {
+  for (const memberInfoInput of memberInfos) {
+    const memberInfo: $Call<
+      ExtractArrayParam,
+      $PropertyType<TI, 'members'>,
+    > = memberInfoInput;
     if (!memberInfo.role) {
       continue;
     }
-    const username = userInfos[memberInfo.id]
+    const username: ?string = userInfos[memberInfo.id]
       ? userInfos[memberInfo.id].username
       : null;
-    if (memberInfo.id === currentUserID) {
-      relativeMemberInfos.unshift({
-        ...memberInfo,
-        username,
-        isViewer: true,
-      });
-    } else {
-      relativeMemberInfos.push({
-        ...memberInfo,
-        username,
-        isViewer: false,
-      });
-    }
+    const isViewer: boolean = memberInfo.id === currentUserID;
+    const relativeMemberInfo: $ReadOnly<{
+      ...$Call<
+        ExtractArrayParam,
+        $PropertyType<TI, 'members'>,
+      >,
+      +username: ?string,
+      +isViewer: boolean,
+    }> = {
+      ...memberInfo,
+      username,
+      isViewer,
+    };
+    relativeMemberInfos.unshift(relativeMemberInfo);
   }
   return relativeMemberInfos;
 }
 
-function getRelativeMemberInfos(
-  threadInfo: ?MinimallyEncodedRawThreadInfo | LegacyRawThreadInfo,
-  currentUserID: ?string,
-  userInfos: UserInfos,
-): $ReadOnlyArray<
-  MinimallyEncodedRelativeMemberInfo | LegacyRelativeMemberInfo,
-> {
-  if (threadInfo?.minimallyEncoded) {
-    return getMinimallyEncodedRelativeMemberInfos(
-      threadInfo,
-      currentUserID,
-      userInfos,
-    );
-  } else {
-    return getLegacyRelativeMemberInfos(threadInfo, currentUserID, userInfos);
-  }
-}
-
 const emptyArray: $ReadOnlyArray<RelativeMemberInfo> = [];
 
 // Includes current user at the start
@@ -298,8 +269,6 @@ const savedEmojiAvatarSelectorForCurrentUser: (
 export {
   userIDsToRelativeUserInfos,
   getRelativeMemberInfos,
-  getMinimallyEncodedRelativeMemberInfos,
-  getLegacyRelativeMemberInfos,
   relativeMemberInfoSelectorForMembersOfThread,
   userInfoSelectorForPotentialMembers,
   userSearchIndexForPotentialMembers,
diff --git a/lib/shared/thread-utils.js b/lib/shared/thread-utils.js
index 4793571e62..df2a3e0a37 100644
--- a/lib/shared/thread-utils.js
+++ b/lib/shared/thread-utils.js
@@ -48,8 +48,7 @@ import {
   threadInfosSelectorForThreadType,
 } from '../selectors/thread-selectors.js';
 import {
-  getLegacyRelativeMemberInfos,
-  getMinimallyEncodedRelativeMemberInfos,
+  getRelativeMemberInfos,
   usersWithPersonalThreadSelector,
 } from '../selectors/user-selectors.js';
 import type { CalendarQuery } from '../types/entry-types.js';
@@ -910,11 +909,9 @@ function threadInfoFromRawThreadInfo(
       parentThreadID: rawThreadInfo.parentThreadID,
       containingThreadID: rawThreadInfo.containingThreadID,
       community: rawThreadInfo.community,
-      members: getMinimallyEncodedRelativeMemberInfos(
-        rawThreadInfo,
-        viewerID,
-        userInfos,
-      ),
+      members: getRelativeMemberInfos<
+        MinimallyEncodedRawThreadInfo,
+      >(rawThreadInfo, viewerID, userInfos),
       roles: rawThreadInfo.roles,
       currentUser: getMinimallyEncodedCurrentUser(
         rawThreadInfo,
@@ -935,7 +932,9 @@ function threadInfoFromRawThreadInfo(
       parentThreadID: rawThreadInfo.parentThreadID,
       containingThreadID: rawThreadInfo.containingThreadID,
       community: rawThreadInfo.community,
-      members: getLegacyRelativeMemberInfos(rawThreadInfo, viewerID, userInfos),
+      members: getRelativeMemberInfos<
+        LegacyRawThreadInfo,
+      >(rawThreadInfo, viewerID, userInfos),
       roles: rawThreadInfo.roles,
       currentUser: getCurrentUser(rawThreadInfo, viewerID, userInfos),
       repliesCount: rawThreadInfo.repliesCount,