yq replace value keep rest intact - yaml

Question

I want just to replace a value in a multi .yaml file with yq and leaving the rest of the document intact. So the question is how do i replace the value of the image key only when the above key value contains name: node-red i have tried:
yq '.spec.template.spec.containers[] | select(.name = "node-red") | .image |= "test"' ./test.yaml`
with this yaml:
---
kind: Ingress
apiVersion: networking.k8s.io/v1
metadata:
name: node-red
spec:
ingressClassName: nginx-private
rules:
- host: node-red.k8s.lan
http:
paths:
- path: "/"
pathType: Prefix
backend:
service:
name: node-red
port:
number: 1880
---
kind: Deployment
apiVersion: apps/v1
metadata:
name: node-red
spec:
replicas: 1
selector:
matchLabels:
app: node-red
template:
metadata:
labels:
app: node-red
spec:
containers:
- name: node-red
image: "cir.domain.com/node-red:84"
the output is:
name: node-red
image: "test"
What I want is a yaml output with only a updated value in the image key like this:
---
kind: Ingress
apiVersion: networking.k8s.io/v1
metadata:
name: node-red
spec:
ingressClassName: nginx-private
rules:
- host: node-red.k8s.lan
http:
paths:
- path: "/"
pathType: Prefix
backend:
service:
name: node-red
port:
number: 1880
---
kind: Deployment
apiVersion: apps/v1
metadata:
name: node-red
spec:
replicas: 1
selector:
matchLabels:
app: node-red
template:
metadata:
labels:
app: node-red
spec:
containers:
- name: node-red
image: "test"

Answer 1

Keep the context by including the traversal and selection into the LHS of the assignment/update, ie. putting parentheses around all of it:
yq '(.spec.template.spec.containers[] | select(.name == "node-red") | .image) |= "test"'
In order to prevent the creation of elements previously not present in one of the documents, add filters using select accordingly, e.g.:
yq '(.spec | select(.template).template.spec.containers[] | select(.name == "node-red").image) |= "test"'
Note that in any case it should read == not = when checking for equality.