IF-THEN-ELSE Conditional with properties attribute (#358)

#357 example from https://json-schema.org/understanding-json-schema/reference/conditionals.html

Author: serebro

src/test/resources/draft7/if-then-else.json

@@ -184,5 +184,69 @@
         "valid": true
       }
     ]
+  },
+  {
+    "description": "conditions by properties",
+    "schema": {
+      "type": "object",
+      "properties": {
+        "street_address": {
+          "type": "string"
+        },
+        "country": {
+          "enum": ["United States of America", "Canada"]
+        }
+      },
+      "if": {
+        "properties": { 
+          "country": { 
+            "const": "United States of America" 
+          } 
+        }
+      },
+      "then": {
+        "properties": { 
+          "postal_code": { 
+            "pattern": "[0-9]{5}(-[0-9]{4})?" 
+          } 
+        }
+      },
+      "else": {
+        "properties": { 
+          "postal_code": { 
+            "pattern": "[A-Z][0-9][A-Z] [0-9][A-Z][0-9]" 
+          } 
+        }
+      }
+    },
+    "tests": [
+      {
+        "description": "valid through then",
+        "data": {
+          "street_address": "1600 Pennsylvania Avenue NW",
+          "country": "United States of America",
+          "postal_code": "20500"
+        },
+        "valid": true
+      },
+      {
+        "description": "valid through else",
+        "data": {
+          "street_address": "24 Sussex Drive",
+          "country": "Canada",
+          "postal_code": "K1M 1M4"
+        },
+        "valid": true
+      },
+      {
+        "description": "invalid",
+        "data": {
+          "street_address": "24 Sussex Drive",
+          "country": "Canada",
+          "postal_code": "10000"
+        },
+        "valid": false
+      }
+    ]
   }
 ]