This query demonstrates that null values are not reverse translated when they mapped with `null_value`

search-null-value-array-object-field

#!/bin/bash

# Clean
curl -XDELETE 'http://localhost:9200/null?pretty'

# Create index 
curl -XPOST 'http://localhost:9200/null?pretty'

# Create mapping
curl -XPOST 'http://localhost:9200/null/type/_mapping?pretty' -d '
{
   "type":{
      "properties":{
         "list":{
            "properties":{
               "x" : {"type" : "string", "null_value" : "-1"}
            }
         }
      }
    }
}'

# Echo mapping
curl -XGET 'http://localhost:9200/null/type/_mapping?pretty'

# Insert document with an array
curl -XPOST 'http://localhost:9200/null/type/?pretty&refresh' -d '
{
   "list":[
      {
         x: "1"
      },
      { 
         x: null 
      },
      {
         x: "2"
      }
   ] 
}'

# Should return a null
curl -XGET 'http://localhost:9200/null/type/_search?pretty' -d '
{
   "fields": ["list.x"],
   "query":{
        "match_all":{}
      }
   }
}'

# Returns the following, which incorrectly returns  [ "1", "2" ] when it should return  [ "1", null, "2" ]
#
#{
#  "hits" : {
#    "total" : 1,
#   "max_score" : 1.0,
#   "hits" : [ {
#     "_index" : "null",
#   "_type" : "type",
#     "_id" : "NzT6KhRURpGLR-kNQTR-Cw",
#   "_score" : 1.0,
#     "fields" : {
#       "list.x" : [ "1", "2" ]
#     }
#   } ]
# }
#}