Fix non-nullable type with two options

If you have a type with exactly two options, neither of which is null,
then the null-checking logic incorrectly uses the last item in the list
as the type instead of interface{}.

e.g. `"type": ["string", "boolean"]` becomes `*bool` instead of `interface{}`

Author: jagregory

pkg/generator/schema_generator.go

@@ -603,7 +603,9 @@ func (g *schemaGenerator) generateTypeInline(
 
 				typeIndex = i
 			}
-		} else if len(t.Type) > 1 {
+		}
+
+		if len(t.Type) > 1 && !typeShouldBePointer {
 			g.warner("Property has multiple types; will be represented as interface{} with no validation")
 
 			return codegen.EmptyInterfaceType{}, nil

tests/data/validation/typeMultiple/typeMultiple.go

@@ -44,6 +44,12 @@
           "null"
         ]
       }
+    },
+    "onlyTwoOptions": {
+      "type": [
+        "number",
+        "boolean"
+      ]
     }
   }
 }