refactor: improve code quality (#8751)

* remove unnecessary if

`Array.prototype.some` already returns a boolean so an if to return
true or false is completely unnecessary in this case.

* perf: use count instead of find

When using `count` instead of `findOneBy`, the data is not
unnecessarily loaded.

* remove duplicate null check

The variable is checked for null in the lines above and the function
returns if so. Therefore, it can not be null at this point.

* simplify `getJsonSchema`

Because the assigned value is `null` and the used keys are only
shallow, use of `nestedProperty.set` seems inappropriate. Because the
value is not read, the initial for loop can be replaced by a `for..in`
loop.

Since all keys will be assigned `null`, the condition of the ternary
expression in the nested function will always be true. Therefore the
recursion case will never happen. With this the nested function can be
eliminated.

* remove duplicate condition

The code above already checks `dragging` and returns if it is truthy.
Checking it again later is therefore unnecessary.

To make this more obvious the `return` is removed in favour of using
an if...else construct.

* remove impossible "unknown" time

The `ago` variable will always be a number and all non-negative numbers
are already covered by other cases, the negative case is handled with
`future` so there is no case when `unkown` could be achieved.

4 files changed, 70 insertions, 69 deletions

diff --git a/packages/backend/src/models/repositories/note.ts b/packages/backend/src/models/repositories/note.ts
index 638d78f626..c0abbb4f93 100644
--- a/packages/backend/src/models/repositories/note.ts
+++ b/packages/backend/src/models/repositories/note.ts
@@ -144,13 +144,7 @@ export const NoteRepository = db.getRepository(Note).extend({
 				return true;
 			} else {
 				// 指定されているかどうか
-				const specified = note.visibleUserIds.some((id: any) => meId === id);
-
-				if (specified) {
-					return true;
-				} else {
-					return false;
-				}
+				return note.visibleUserIds.some((id: any) => meId === id);
 			}
 		}
 
@@ -169,9 +163,12 @@ export const NoteRepository = db.getRepository(Note).extend({
 			} else {
 				// フォロワーかどうか
 				const [following, user] = await Promise.all([
-					Followings.findOneBy({
-						followeeId: note.userId,
-						followerId: meId,
+					Followings.count({
+						where: {
+							followeeId: note.userId,
+							followerId: meId,
+						},
+						take: 1,
 					}),
 					Users.findOneByOrFail({ id: meId }),
 				]);
@@ -183,7 +180,7 @@ export const NoteRepository = db.getRepository(Note).extend({
 				in which case we can never know the following. Instead we have
 				to assume that the users are following each other.
 				*/
-				return following != null || (note.userHost != null && user.host != null);
+				return following > 0 || (note.userHost != null && user.host != null);
 			}
 		}
 
diff --git a/packages/backend/src/models/repositories/user.ts b/packages/backend/src/models/repositories/user.ts
index 541fbaf003..8a4e48efdd 100644
--- a/packages/backend/src/models/repositories/user.ts
+++ b/packages/backend/src/models/repositories/user.ts
@@ -61,47 +61,58 @@ export const UserRepository = db.getRepository(User).extend({
 	//#endregion
 
 	async getRelation(me: User['id'], target: User['id']) {
-		const [following1, following2, followReq1, followReq2, toBlocking, fromBlocked, mute] = await Promise.all([
-			Followings.findOneBy({
-				followerId: me,
-				followeeId: target,
-			}),
-			Followings.findOneBy({
-				followerId: target,
-				followeeId: me,
-			}),
-			FollowRequests.findOneBy({
-				followerId: me,
-				followeeId: target,
-			}),
-			FollowRequests.findOneBy({
-				followerId: target,
-				followeeId: me,
-			}),
-			Blockings.findOneBy({
-				blockerId: me,
-				blockeeId: target,
-			}),
-			Blockings.findOneBy({
-				blockerId: target,
-				blockeeId: me,
-			}),
-			Mutings.findOneBy({
-				muterId: me,
-				muteeId: target,
-			}),
-		]);
-
-		return {
+		return awaitAll({
 			id: target,
-			isFollowing: following1 != null,
-			hasPendingFollowRequestFromYou: followReq1 != null,
-			hasPendingFollowRequestToYou: followReq2 != null,
-			isFollowed: following2 != null,
-			isBlocking: toBlocking != null,
-			isBlocked: fromBlocked != null,
-			isMuted: mute != null,
-		};
+			isFollowing: Followings.count({
+				where: {
+					followerId: me,
+					followeeId: target,
+				},
+				take: 1,
+			}).then(n => n > 0),
+			isFollowed: Followings.count({
+				where: {
+					followerId: target,
+					followeeId: me,
+				},
+				take: 1,
+			}).then(n => n > 0),
+			hasPendingFollowRequestFromYou: FollowRequests.count({
+				where: {
+					followerId: me,
+					followeeId: target,
+				},
+				take: 1,
+			}).then(n => n > 0),
+			hasPendingFollowRequestToYou: FollowRequests.count({
+				where: {
+					followerId: target,
+					followeeId: me,
+				},
+				take: 1,
+			}).then(n => n > 0),
+			isBlocking: Blockings.count({
+				where: {
+					blockerId: me,
+					blockeeId: target,
+				},
+				take: 1,
+			}).then(n => n > 0),
+			isBlocked: Blockings.count({
+				where: {
+					blockerId: target,
+					blockeeId: me,
+				},
+				take: 1,
+			}).then(n => n > 0),
+			isMuted: Mutings.count({
+				where: {
+					muterId: me,
+					muteeId: target,
+				},
+				take: 1,
+			}).then(n => n > 0),
+		});
 	},
 
 	async getHasUnreadMessagingMessage(userId: User['id']): Promise<boolean> {
diff --git a/packages/backend/src/remote/activitypub/renderer/index.ts b/packages/backend/src/remote/activitypub/renderer/index.ts
index 5f69332266..f100b77ce5 100644
--- a/packages/backend/src/remote/activitypub/renderer/index.ts
+++ b/packages/backend/src/remote/activitypub/renderer/index.ts
@@ -8,7 +8,7 @@ import { User } from '@/models/entities/user.js';
 export const renderActivity = (x: any): IActivity | null => {
 	if (x == null) return null;
 
-	if (x !== null && typeof x === 'object' && x.id == null) {
+	if (typeof x === 'object' && x.id == null) {
 		x.id = `${config.url}/${uuid()}`;
 	}
 
diff --git a/packages/backend/src/services/chart/core.ts b/packages/backend/src/services/chart/core.ts
index cf69e2194d..2960bac8f7 100644
--- a/packages/backend/src/services/chart/core.ts
+++ b/packages/backend/src/services/chart/core.ts
@@ -91,27 +91,20 @@ type ToJsonSchema<S> = {
 };
 
 export function getJsonSchema<S extends Schema>(schema: S): ToJsonSchema<Unflatten<ChartResult<S>>> {
-	const object = {};
-	for (const [k, v] of Object.entries(schema)) {
-		nestedProperty.set(object, k, null);
-	}
+	const jsonSchema = {
+		type: 'object',
+		properties: {} as Record<string, unknown>,
+		required: [],
+	};
 
-	function f(obj: Record<string, null | Record<string, unknown>>) {
-		const jsonSchema = {
-			type: 'object',
-			properties: {} as Record<string, unknown>,
-			required: [],
+	for (const k in schema) {
+		jsonSchema.properties[k] = {
+			type: 'array',
+			items: { type: 'number' },
 		};
-		for (const [k, v] of Object.entries(obj)) {
-			jsonSchema.properties[k] = v === null ? {
-				type: 'array',
-				items: { type: 'number' },
-			} : f(v as Record<string, null | Record<string, unknown>>);
-		}
-		return jsonSchema;
 	}
 
-	return f(object) as ToJsonSchema<Unflatten<ChartResult<S>>>;
+	return jsonSchema as ToJsonSchema<Unflatten<ChartResult<S>>>;
 }
 
 /**