From 6f9f80cc4805af949195c0bf605475588304022f Mon Sep 17 00:00:00 2001
From: Mike Farah <mikefarah@gmail.com>
Date: Thu, 14 Apr 2022 12:03:18 +1000
Subject: [PATCH] Fixes with operation bug #1174

---
 pkg/yqlib/operator_with.go      | 10 +++++++---
 pkg/yqlib/operator_with_test.go | 10 ++++++++++
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/pkg/yqlib/operator_with.go b/pkg/yqlib/operator_with.go
index 87726267..92da7348 100644
--- a/pkg/yqlib/operator_with.go
+++ b/pkg/yqlib/operator_with.go
@@ -20,9 +20,13 @@ func withOperator(d *dataTreeNavigator, context Context, expressionNode *Express
 
 	updateExp := expressionNode.RHS.RHS
 
-	_, err = d.GetMatchingNodes(updateContext, updateExp)
-	if err != nil {
-		return Context{}, err
+	for el := updateContext.MatchingNodes.Front(); el != nil; el = el.Next() {
+		candidate := el.Value.(*CandidateNode)
+		_, err = d.GetMatchingNodes(updateContext.SingleChildContext(candidate), updateExp)
+		if err != nil {
+			return Context{}, err
+		}
+
 	}
 
 	return context, nil
diff --git a/pkg/yqlib/operator_with_test.go b/pkg/yqlib/operator_with_test.go
index aad4d15c..04f184c2 100644
--- a/pkg/yqlib/operator_with_test.go
+++ b/pkg/yqlib/operator_with_test.go
@@ -28,6 +28,16 @@ var withOperatorScenarios = []expressionScenario{
 			"D0, P[], (doc)::myArray: [{a: apple, b: apple yum}, {a: banana, b: banana yum}]\n",
 		},
 	},
+	{
+		description:    "Update array elements relatively +=",
+		skipDoc:        true,
+		subdescription: "The second expression runs with each element of the array as it's contextual root. This allows you to make updates relative to the element.",
+		document:       `myArray: [{a: apple},{a: banana}]`,
+		expression:     `with(.myArray[]; .a += .a)`,
+		expected: []string{
+			"D0, P[], (doc)::myArray: [{a: appleapple}, {a: bananabanana}]\n",
+		},
+	},
 }
 
 func TestWithOperatorScenarios(t *testing.T) {