From fec607da20ca784b66f25f3ee4ad5ba6223d976c Mon Sep 17 00:00:00 2001
From: Alice Gaudon <alice@gaudon.pro>
Date: Fri, 11 Sep 2020 15:15:15 +0200
Subject: [PATCH] ModelQuery: add offset parameter to union()

---
 src/db/ModelQuery.ts | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/db/ModelQuery.ts b/src/db/ModelQuery.ts
index 7ac5da3..fad6252 100644
--- a/src/db/ModelQuery.ts
+++ b/src/db/ModelQuery.ts
@@ -124,7 +124,7 @@ export default class ModelQuery<M extends Model> implements WhereFieldConsumer<M
         return this;
     }
 
-    public union(query: ModelQuery<any>, sortBy: string, direction: SortDirection = 'ASC', raw: boolean = false, limit?: number): this {
+    public union(query: ModelQuery<any>, sortBy: string, direction: SortDirection = 'ASC', raw: boolean = false, limit?: number, offset?: number): this {
         if (this.type !== QueryType.SELECT) throw new Error('Union queries are only implemented with SELECT.');
 
         this._union = {
@@ -132,6 +132,7 @@ export default class ModelQuery<M extends Model> implements WhereFieldConsumer<M
             sortBy: raw ? sortBy : inputToFieldOrValue(sortBy),
             direction: direction,
             limit: limit,
+            offset: offset,
         };
         return this;
     }
@@ -207,7 +208,8 @@ export default class ModelQuery<M extends Model> implements WhereFieldConsumer<M
                 if (this._union) {
                     const unionOrderBy = this._union.sortBy ? ` ORDER BY ${this._union.sortBy} ${this._union.direction}` : '';
                     const unionLimit = typeof this._union.limit === 'number' ? ` LIMIT ${this._union.limit}` : '';
-                    query = `(${query}) UNION ${this._union.query.toString(false)}${unionOrderBy}${unionLimit}`;
+                    const unionOffset = typeof this._union.offset === 'number' ? ` OFFSET ${this._union.offset}` : '';
+                    query = `(${query}) UNION ${this._union.query.toString(false)}${unionOrderBy}${unionLimit}${unionOffset}`;
                 }
                 break;
             case QueryType.UPDATE:
@@ -448,7 +450,7 @@ class WhereFieldValueGroup {
     }
 }
 
-interface WhereFieldConsumer<M extends Model> {
+export interface WhereFieldConsumer<M extends Model> {
     where(field: string, value: string | Date | ModelQuery<any> | any, test?: WhereTest, operator?: WhereOperator): this;
 
     groupWhere(setter: (query: WhereFieldConsumer<M>) => void, operator?: WhereOperator): this;
@@ -463,4 +465,5 @@ type ModelQueryUnion = {
     sortBy: string,
     direction: SortDirection,
     limit?: number,
+    offset?: number,
 };