From 10600dd29a4a5d7ea01f5311425837890127988e Mon Sep 17 00:00:00 2001
From: Mike Farah <mikefarah@gmail.com>
Date: Thu, 4 Feb 2021 12:48:07 +1100
Subject: [PATCH] Fixed delete bug

---
 pkg/yqlib/operator_delete.go      |  4 ++--
 pkg/yqlib/operator_delete_test.go | 16 ++++++++++++++++
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/pkg/yqlib/operator_delete.go b/pkg/yqlib/operator_delete.go
index abda4cd2..f28569a9 100644
--- a/pkg/yqlib/operator_delete.go
+++ b/pkg/yqlib/operator_delete.go
@@ -13,8 +13,8 @@ func deleteChildOperator(d *dataTreeNavigator, context Context, expressionNode *
 	if err != nil {
 		return Context{}, err
 	}
-
-	for el := nodesToDelete.MatchingNodes.Front(); el != nil; el = el.Next() {
+	//need to iterate backwards to ensure correct indices when deleting multiple
+	for el := nodesToDelete.MatchingNodes.Back(); el != nil; el = el.Prev() {
 		candidate := el.Value.(*CandidateNode)
 
 		deleteImmediateChildOp := &Operation{
diff --git a/pkg/yqlib/operator_delete_test.go b/pkg/yqlib/operator_delete_test.go
index f7fe831c..364f271e 100644
--- a/pkg/yqlib/operator_delete_test.go
+++ b/pkg/yqlib/operator_delete_test.go
@@ -37,6 +37,22 @@ var deleteOperatorScenarios = []expressionScenario{
 			"D0, P[], (doc)::[1, 3]\n",
 		},
 	},
+	{
+		skipDoc:    true,
+		document:   `a: [1,2,3]`,
+		expression: `del(.a[])`,
+		expected: []string{
+			"D0, P[], (doc)::a: []\n",
+		},
+	},
+	{
+		skipDoc:    true,
+		document:   `a: [10,x,10, 10, x, 10]`,
+		expression: `del(.a[] | select(. == 10))`,
+		expected: []string{
+			"D0, P[], (doc)::a: [x, x]\n",
+		},
+	},
 	{
 		description: "Delete nested entry in array",
 		document:    `[{a: cat, b: dog}]`,