Make positions possibly negatives (#5690)

Closes https://github.com/twentyhq/twenty/issues/5427

packages/twenty-server/src/engine/api/graphql/workspace-query-runner/factories/__tests__/record-position.factory.spec.ts

@@ -48,11 +48,11 @@ describe('RecordPositionFactory', () => {
 
       expect(result).toEqual(value);
     });
-    it('should return the existing position / 2 when value is first', async () => {
+    it('should return the existing position -1 when value is first', async () => {
       const value = 'first';
       const result = await factory.create(value, objectMetadata, workspaceId);
 
-      expect(result).toEqual(0.5);
+      expect(result).toEqual(0);
     });
     it('should return the existing position + 1 when value is last', async () => {
       const value = 'last';

packages/twenty-server/src/engine/api/graphql/workspace-query-runner/factories/record-position.factory.ts

@@ -1,5 +1,7 @@
 import { Injectable } from '@nestjs/common';
 
+import { isDefined } from 'class-validator';
+
 import { WorkspaceDataSourceService } from 'src/engine/workspace-datasource/workspace-datasource.service';
 import {
   RecordPositionQueryFactory,
@@ -32,6 +34,8 @@ export class RecordPositionFactory {
       dataSourceSchema,
     );
 
+    // If the value was 'first', the first record will be the one with the lowest position
+    // If the value was 'last', the first record will be the one with the highest position
     const records = await this.workspaceDataSourceService.executeRawQuery(
       query,
       [],
@@ -39,10 +43,16 @@ export class RecordPositionFactory {
       undefined,
     );
 
-    return (
-      (value === 'first'
-        ? records[0]?.position / 2
-        : records[0]?.position + 1) || 1
-    );
+    if (
+      !isDefined(records) ||
+      records.length === 0 ||
+      !isDefined(records[0]?.position)
+    ) {
+      return 1;
+    }
+
+    return value === 'first'
+      ? records[0].position - 1
+      : records[0].position + 1;
   }
 }

packages/twenty-server/src/engine/api/graphql/workspace-schema-builder/graphql-types/scalars/position.scalar.ts

@@ -6,7 +6,7 @@ const isValidStringPosition = (value: string): boolean =>
   typeof value === 'string' && (value === 'first' || value === 'last');
 
 const isValidNumberPosition = (value: number): boolean =>
-  typeof value === 'number' && value >= 0;
+  typeof value === 'number';
 
 const checkPosition = (value: any): PositionType => {
   if (isValidNumberPosition(value) || isValidStringPosition(value)) {