Typescript: Start fixing strictFunctionTypes errors

app/soapbox/reducers/accounts.ts

@@ -1,6 +1,7 @@
 import {
   Map as ImmutableMap,
   List as ImmutableList,
+  OrderedSet as ImmutableOrderedSet,
   fromJS,
 } from 'immutable';
 import { AnyAction } from 'redux';
@@ -82,8 +83,8 @@ const addTags = (
 ): State => {
   return state.withMutations(state => {
     accountIds.forEach(id => {
-      state.updateIn([id, 'pleroma', 'tags'], ImmutableList(), (v: ImmutableList<string>) =>
-        v.toOrderedSet().union(tags).toList(),
+      state.updateIn([id, 'pleroma', 'tags'], ImmutableList(), v =>
+        ImmutableOrderedSet(fromJS(v)).union(tags).toList(),
       );
     });
   });
@@ -96,8 +97,8 @@ const removeTags = (
 ): State => {
   return state.withMutations(state => {
     accountIds.forEach(id => {
-      state.updateIn([id, 'pleroma', 'tags'], ImmutableList(), (v: ImmutableList<string>) =>
-        v.toOrderedSet().subtract(tags).toList(),
+      state.updateIn([id, 'pleroma', 'tags'], ImmutableList(), v =>
+        ImmutableOrderedSet(fromJS(v)).subtract(tags).toList(),
       );
     });
   });

app/soapbox/reducers/statuses.ts

@@ -136,7 +136,9 @@ const deleteStatus = (state: State, id: string, references: Array<string>) => {
 
 const importPendingStatus = (state: State, { in_reply_to_id }: APIEntity) => {
   if (in_reply_to_id) {
-    return state.updateIn([in_reply_to_id, 'replies_count'], 0, (count: number) => count + 1);
+    return state.updateIn([in_reply_to_id, 'replies_count'], 0, count => {
+      return typeof count === 'number' ? count + 1 : 0;
+    });
   } else {
     return state;
   }
@@ -144,7 +146,9 @@ const importPendingStatus = (state: State, { in_reply_to_id }: APIEntity) => {
 
 const deletePendingStatus = (state: State, { in_reply_to_id }: APIEntity) => {
   if (in_reply_to_id) {
-    return state.updateIn([in_reply_to_id, 'replies_count'], 0, (count: number) => Math.max(0, count - 1));
+    return state.updateIn([in_reply_to_id, 'replies_count'], 0, count => {
+      return typeof count === 'number' ? Math.max(0, count - 1) : 0;
+    });
   } else {
     return state;
   }

tsconfig.json

@@ -5,7 +5,7 @@
     "alwaysStrict": true,
     "strictNullChecks": false,
     "strictBindCallApply": true,
-    "strictFunctionTypes": false,
+    "strictFunctionTypes": true,
     "strictPropertyInitialization": false,
     "noImplicitAny": true,
     "noImplicitThis": true,