From e3c660b9b91630e7db46fe8341a490ed32c0df9d Mon Sep 17 00:00:00 2001
From: Maciej Holyszko <14310995+falkenhawk@users.noreply.github.com>
Date: Thu, 22 Dec 2022 16:27:33 +0100
Subject: [PATCH] fix: overwriting already existing query's context in
 `childQueryOf`

This is a fix for an edge case, where a query context could be already set in a `Model.query()` call or in a custom QueryBuilder's constructor.
In our case we are defining columns with a custom `@DefaultOrderBy(columns)` decorator, they are stored to query's context after query builder is instantiated, and eventually are read in `query.onBuild()` hook to apply sorting for a query, if none other was provided to it in the meantime.
But when coupled with fetching graphs, where both parent and children models have `@DefaultOrderBy` configured, child model's query context (eager query to fetch models for a relation) was being completely overwritten with parent's query context, and that, in our case, resulted in using invalid columns to be passed to `orderBy()`, resulting in a sql error.
---
 lib/queryBuilder/QueryBuilderOperationSupport.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/lib/queryBuilder/QueryBuilderOperationSupport.js b/lib/queryBuilder/QueryBuilderOperationSupport.js
index 4c7159bdf..090ec60be 100644
--- a/lib/queryBuilder/QueryBuilderOperationSupport.js
+++ b/lib/queryBuilder/QueryBuilderOperationSupport.js
@@ -153,6 +153,7 @@ class QueryBuilderOperationSupport {
 
   childQueryOf(query, { fork, isInternalQuery } = {}) {
     if (query) {
+      let currentCtx = this.context();
       let ctx = query.internalContext();
 
       if (fork) {
@@ -165,6 +166,7 @@ class QueryBuilderOperationSupport {
 
       this._parentQuery = query;
       this.internalContext(ctx);
+      this.context(currentCtx);
 
       // Use the parent's knex if there was no knex in `ctx`.
       if (this.unsafeKnex() === null) {