{
   "comments":
   [ " This is a JSON Schema for 'canonical-data.json' files.     "
   , "                                                            "
   , " It enforces just a general structure for all exercises,    "
   , " without specifying how the test data should be organized   "
   , " for each type of test. We do this to keep generality and   "
   , " allow support for tests the do not fit well in the         "
   , " 'function (input) == output' structure, like property      "
   , " tests.                                                     "
   , "                                                            "
   , " The only thing enforced regarding how test data should be  "
   , " structured is the error encoding, because it was agreed    "
   , " and it doesn't restrict flexibility in a significant way.  "
   , "                                                            "
   , " Standardized property names may help when automatically    "
   , " deriving JSON parsers in some languages, so we followed    "
   , " a few conventions from the 'Google JSON Style Guide'.      "
   , "                                                            "
   , " Additionally, this schema strictly enforces letters, in    "
   , " lowerCamelCase, for naming the 'property' being tested. We "
   , " expect this regularity will allow an easier automatic      "
   , " generation of function's names in test generators,         "
   , " slightly reducing the amount of manually generated code.   "
   ],

   "$schema": "http://json-schema.org/draft-04/schema#",

   "self": { "vendor" : "io.exercism"
           , "name"   : "canonical-data"
           , "format" : "jsonschema"
           , "version": "1-0-0"
           },

   "$ref": "#/definitions/canonicalData",

   "definitions":{

      "canonicalData":
          { "description": "This is the top-level file structure"
          , "type"       : "object"
          , "required"   : ["exercise" , "version", "cases"]
          , "properties" :
                { "exercise" : { "$ref": "#/definitions/exercise"  }
                , "version"  : { "$ref": "#/definitions/version"   }
                , "comments" : { "$ref": "#/definitions/comments"  }
                , "cases"    : { "$ref": "#/definitions/testGroup" }
                }
          , "additionalProperties": false
          },

      "exercise":
          { "description": "Exercise's slug (kebab-case)"
          , "type"       : "string"
          , "pattern"    : "^[a-z]+(-[a-z]+)*$"
          },

      "version" :
          { "description" : "Semantic versioning: MAJOR.MINOR.PATCH"
          , "type"        : "string"
          , "pattern"     : "^(0|[1-9][0-9]*)(\\.(0|[1-9][0-9]*)){2}$"
          },

      "comments":
          { "description": "An array of strings to fake multi-line comments"
          , "type"       : "array"
          , "items"      : { "type": "string" }
          , "minItems"   : 1
          },

      "testGroup":
          { "description": "An array of labeled test items"
          , "type"       : "array"
          , "items"      : { "$ref": "#/definitions/labeledTestItem" }
          , "minItems"   : 1
          },

      "labeledTestItem":
          { "description": "A single test or group of tests with a description"
          , "oneOf": [ { "$ref": "#/definitions/labeledTest"      }
                     , { "$ref": "#/definitions/labeledTestGroup" }
                     ]
          },

      "labeledTest":
          { "description": "A single test with a description"
          , "type"       : "object"
          , "required"   : ["description", "property"]
          , "properties" :
                { "description": { "$ref": "#/definitions/description" }
                , "comments"   : { "$ref": "#/definitions/comments"    }
                , "property"   : { "$ref": "#/definitions/property"    }
                , "expected"   : { "$ref": "#/definitions/expected"    }
                }
          },

      "labeledTestGroup":
          { "description": "A group of tests with a description"
          , "type"       : "object"
          , "required"   : ["description", "cases"]
          , "properties" :
                { "description": { "$ref": "#/definitions/description" }
                , "comments"   : { "$ref": "#/definitions/comments"    }
                , "cases"      : { "$ref": "#/definitions/testGroup"   }
                }
          , "additionalProperties": false
          },

      "description":
          { "description": "A short, clear, one-line description"
          , "type"       : "string"
          },

      "property":
          { "description": "A letters-only, lowerCamelCase property name"
          , "type"       : "string"
          , "pattern"    : "^[a-z]+([A-Z][a-z]+)*[A-Z]?$"
          },

      "expected":
          { "description": "The expected return value of a test case"
          , "properties":
               { "error": { "$ref": "#/definitions/error" }
               }
          , "dependencies":
               { "error": { "maxProperties": 1 }
               }
          },

      "error":
          { "description": "A message describing an error condition"
          , "type"       : "string"
          }

    }

}