Give unsigned int schemas explicit minimum value

schemars/src/json_schema_impls/primitives.rs

@@ -42,12 +42,6 @@ simple_impl!(i32 => Integer, "int32");
 simple_impl!(i64 => Integer, "int64");
 simple_impl!(i128 => Integer, "int128");
 simple_impl!(isize => Integer, "int");
-simple_impl!(u8 => Integer, "uint8");
-simple_impl!(u16 => Integer, "uint16");
-simple_impl!(u32 => Integer, "uint32");
-simple_impl!(u64 => Integer, "uint64");
-simple_impl!(u128 => Integer, "uint128");
-simple_impl!(usize => Integer, "uint");
 simple_impl!(() => Null);
 
 simple_impl!(Path => String);
@@ -61,6 +55,35 @@ simple_impl!(SocketAddr => String);
 simple_impl!(SocketAddrV4 => String);
 simple_impl!(SocketAddrV6 => String);
 
+macro_rules! unsigned_impl {
+    ($type:ty => $instance_type:ident, $format:expr) => {
+        impl JsonSchema for $type {
+            no_ref_schema!();
+
+            fn schema_name() -> String {
+                $format.to_owned()
+            }
+
+            fn json_schema(_: &mut SchemaGenerator) -> Schema {
+                let mut schema = SchemaObject {
+                    instance_type: Some(InstanceType::$instance_type.into()),
+                    format: Some($format.to_owned()),
+                    ..Default::default()
+                };
+                schema.number().minimum = Some(0.0);
+                schema.into()
+            }
+        }
+    };
+}
+
+unsigned_impl!(u8 => Integer, "uint8");
+unsigned_impl!(u16 => Integer, "uint16");
+unsigned_impl!(u32 => Integer, "uint32");
+unsigned_impl!(u64 => Integer, "uint64");
+unsigned_impl!(u128 => Integer, "uint128");
+unsigned_impl!(usize => Integer, "uint");
+
 impl JsonSchema for char {
     no_ref_schema!();
 

schemars/tests/expected/duration_and_systemtime.json

@@ -24,11 +24,13 @@
       "properties": {
         "nanos": {
           "type": "integer",
-          "format": "uint32"
+          "format": "uint32",
+          "minimum": 0.0
         },
         "secs": {
           "type": "integer",
-          "format": "uint64"
+          "format": "uint64",
+          "minimum": 0.0
         }
       }
     },
@@ -41,11 +43,13 @@
       "properties": {
         "nanos_since_epoch": {
           "type": "integer",
-          "format": "uint32"
+          "format": "uint32",
+          "minimum": 0.0
         },
         "secs_since_epoch": {
           "type": "integer",
-          "format": "uint64"
+          "format": "uint64",
+          "minimum": 0.0
         }
       }
     }

schemars/tests/expected/nonzero_ints.json

@@ -27,7 +27,8 @@
     },
     "unsigned": {
       "type": "integer",
-      "format": "uint32"
+      "format": "uint32",
+      "minimum": 0.0
     }
   }
 }

schemars/tests/expected/os_strings.json

@@ -27,7 +27,8 @@
               "type": "array",
               "items": {
                 "type": "integer",
-                "format": "uint8"
+                "format": "uint8",
+                "minimum": 0.0
               }
             }
           }
@@ -42,7 +43,8 @@
               "type": "array",
               "items": {
                 "type": "integer",
-                "format": "uint16"
+                "format": "uint16",
+                "minimum": 0.0
               }
             }
           }

schemars/tests/expected/range.json

@@ -41,11 +41,13 @@
       "properties": {
         "end": {
           "type": "integer",
-          "format": "uint"
+          "format": "uint",
+          "minimum": 0.0
         },
         "start": {
           "type": "integer",
-          "format": "uint"
+          "format": "uint",
+          "minimum": 0.0
         }
       }
     }