Exclude skipped fields/variants from json schema

schemars/tests/expected/skip_enum_variants.json

@@ -0,0 +1,23 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "MyEnum",
+  "anyOf": [
+    {
+      "enum": [
+        "Included2"
+      ]
+    },
+    {
+      "type": "object",
+      "properties": {
+        "Included1": {
+          "type": "number",
+          "format": "float"
+        }
+      },
+      "required": [
+        "Included1"
+      ]
+    }
+  ]
+}

schemars/tests/expected/skip_struct_fields.json

@@ -0,0 +1,18 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "MyStruct",
+  "type": "object",
+  "properties": {
+    "included1": {
+      "type": "number",
+      "format": "float"
+    },
+    "included2": {
+      "type": "null"
+    }
+  },
+  "required": [
+    "included1",
+    "included2"
+  ]
+}

schemars/tests/expected/skip_tuple_fields.json

@@ -0,0 +1,16 @@
+{
+  "$schema": "http://json-schema.org/draft-07/schema#",
+  "title": "TupleStruct",
+  "type": "array",
+  "items": [
+    {
+      "type": "number",
+      "format": "float"
+    },
+    {
+      "type": "null"
+    }
+  ],
+  "maxItems": 2,
+  "minItems": 2
+}