}
	}
	buffer.Write(hostsEntriesFromHostAliases(hostAliases))
	return buffer.Bytes()
}

func hostsEntriesFromHostAliases(hostAliases []v1.HostAlias) []byte {
	if len(hostAliases) == 0 {
		return []byte{}
	}

	var buffer bytes.Buffer
	buffer.WriteString("\n")
	buffer.WriteString("# Entries added by HostAliases.\n")
	// for each IP, write all aliases onto single line in hosts file

func TestNodeHostsFileContent(t *testing.T) {
	testCases := []struct {
		hostsFileName            string
		hostAliases              []v1.HostAlias
		rawHostsFileContent      string
		expectedHostsFileContent string
	}{
		{
			hostsFileName: "hosts_test_file1",
			hostAliases:   []v1.HostAlias{},
			rawHostsFileContent: `# hosts file for testing.
127.0.0.1	localhost
::1	localhost ip6-localhost ip6-loopback

        nameservers:
        - "8.8.8.8"
        options:
        - name: "ndots"
          value: "1"
{{- if $.VM.IstioHost }}
      # Override the istiod host to force traffic through east-west gateway.
      hostAliases:
      - ip: {{ $.VM.IstioIP }}
        hostnames:
        - {{ $.VM.IstioHost }}
{{- end }}
      # Disable service account mount, to mirror VM
      automountServiceAccountToken: false

            "operator": "operatorValue",
            "value": "valueValue",
            "effect": "effectValue",
            "tolerationSeconds": 5
          }
        ],
        "hostAliases": [
          {
            "ip": "ipValue",
            "hostnames": [
              "hostnamesValue"
            ]
          }
        ],
        "priorityClassName": "priorityClassNameValue",

          readOnly: true
          recursiveReadOnly: recursiveReadOnlyValue
          subPath: subPathValue
          subPathExpr: subPathExprValue
        workingDir: workingDirValue
      hostAliases:
      - hostnames:
        - hostnamesValue
        ip: ipValue
      hostIPC: true
      hostNetwork: true
      hostPID: true
      hostUsers: true
      hostname: hostnameValue

            "operator": "operatorValue",
            "value": "valueValue",
            "effect": "effectValue",
            "tolerationSeconds": 5
          }
        ],
        "hostAliases": [
          {
            "ip": "ipValue",
            "hostnames": [
              "hostnamesValue"
            ]
          }
        ],
        "priorityClassName": "priorityClassNameValue",

          readOnly: true
          recursiveReadOnly: recursiveReadOnlyValue
          subPath: subPathValue
          subPathExpr: subPathExprValue
        workingDir: workingDirValue
      hostAliases:
      - hostnames:
        - hostnamesValue
        ip: ipValue
      hostIPC: true
      hostNetwork: true
      hostPID: true
      hostUsers: true
      hostname: hostnameValue

            "operator": "operatorValue",
            "value": "valueValue",
            "effect": "effectValue",
            "tolerationSeconds": 5
          }
        ],
        "hostAliases": [
          {
            "ip": "ipValue",
            "hostnames": [
              "hostnamesValue"
            ]
          }
        ],
        "priorityClassName": "priorityClassNameValue",

            "operator": "operatorValue",
            "value": "valueValue",
            "effect": "effectValue",
            "tolerationSeconds": 5
          }
        ],
        "hostAliases": [
          {
            "ip": "ipValue",
            "hostnames": [
              "hostnamesValue"
            ]
          }
        ],
        "priorityClassName": "priorityClassNameValue",

          readOnly: true
          recursiveReadOnly: recursiveReadOnlyValue
          subPath: subPathValue
          subPathExpr: subPathExprValue
        workingDir: workingDirValue
      hostAliases:
      - hostnames:
        - hostnamesValue
        ip: ipValue
      hostIPC: true
      hostNetwork: true
      hostPID: true
      hostUsers: true
      hostname: hostnameValue