on apply error, from kubectl edit, we should indicate the suspect line number

[starpit]

this will require parsing out the low-level kubectl message. e.g. in the following error, the line prefixed with "-" is the one we would like to mark in monaco-editor. we could use monaco's line markers to do so.

Error: The Pod "kui-two-containers" is invalid: spec: Forbidden: pod updates may not change fields other than `spec.containers[*].image`, `spec.initContainers[*].image`, `spec.activeDeadlineSeconds` or `spec.tolerations` (only additions to existing tolerations)
  core.PodSpec{
  	Volumes:        []core.Volume{{Name: "default-token-7w5df", VolumeSource: core.VolumeSource{Secret: &core.SecretVolumeSource{SecretName: "default-token-7w5df", DefaultMode: &420}}}},
  	InitContainers: nil,
  	Containers: []core.Container{
  		{
  			Name:  "a",
  			Image: "jare/alpine-vim",
  			Command: []string{
  				"/bin/sh",
  				"-c",
- 				"while true; do echo a; sleep 2; done",
+ 				"while true; do echo a; sleep 1; done",
  			},
  			Args:       nil,
  			WorkingDir: "",
  			... // 16 identical fields
  		},
  		{Name: "b", Image: "jare/alpine-vim", Command: []string{"/bin/sh", "-c", "while true; do echo b; sleep 1; done"}, VolumeMounts: []core.VolumeMount{{Name: "default-token-7w5df", ReadOnly: true, MountPath: "/var/run/secrets/kubernetes.io/serviceaccount"}}, TerminationMessagePath: "/dev/termination-log", TerminationMessagePolicy: "File", ImagePullPolicy: "Always"},
  	},
  	RestartPolicy:                 "Always",
  	TerminationGracePeriodSeconds: &30,
  	... // 21 identical fields
  }

[starpit]

a candidate algorithm, if errMsg is the above example, as a string, and yaml is the source, as as a string:

1. const s = yaml.split(/\n/)
2. const m = errMsg.split(/\n/)
3. const x = x = m[m.findIndex(_ => /^-\s/.test(_))].replace(/^-\s/, '').trim().replace(/^"(.*)",?$/, '$1')
4. const idx = s.findIndex(_ => _.indexOf(x) >= 0)

x is the important part of the line of the error message that indicates the failure, and idx is the line index of s that contains that x

x is the ugly part, because of the way kubectl encodes things. we have to unwrap the leading “-”, then remove whatever whitespace it might add (because kubectl’s whitespace is not the same as in the original s), then kubectl adds quotation marks, and possibly a trailing comma

[starpit]

we may also want to link to the line numbers in the error alert. i.e. in a way that causes the monaco editor to scroll that line into view.