json!() macro recursion limit reached on larger objects with no nesting

[bgmerrell]

The code below (which I use for unit testing) fails with the error below. If I use serde_json::from_str() the same JSON as a string is parsed with no problems. Is this expected?

The error can be reproduced trivially here: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=c9b62d7c6508bf68f007336f91e2788a

error: recursion limit reached while expanding `json_internal!`
  --> src/main.rs:2:13
   |
2  |       let _ = serde_json::json!({
   |  _____________^
3  | |         "EnableFeature1": true,
4  | |         "EnforceOperationFoo": true,
5  | |         "EnforceOperationBar": true,
...  |
44 | |         "PropertyPathPrefix": "/etc/foo/bar/baz/company/SOMETHING/my-service"
45 | |     });
   | |______^
   |
   = help: consider increasing the recursion limit by adding a `#![recursion_limit = "256"]` attribute to your crate (`playground`)
   = note: this error originates in the macro `json_internal` which comes from the expansion of the macro `serde_json::json` (in Nightly builds, run with -Z macro-backtrace for more info)

fn main() {
    let _ = serde_json::json!({
        "EnableFeature1": true,
        "EnforceOperationFoo": true,
        "EnforceOperationBar": true,
        "EnableFeature2": true,
        "DoAThing": true,
        "DoAnotherThing": true,
        "DoSomethingElse": true,
        "DoYetAnotherThing": true,
        "BlockAThing": true,
        "StrictBlockingOfSomething": 12,
        "AllowedNamesOfOtherThings": 13,
        "PollingInterval": 60,
        "MyStatsURL": "http://foo.company.com/usage",
        "AppName": "My Service",
        "EnableRetryForDoingAThing": true,
        "RetryLimitForDoingAThing": 2,
        "MGqlRegistryEndpoint": "http://company.net/foo/bar/baz",
        "RegistryArchivedUrl": "http://foo.bar.k8s.glb.us.company.net/foo/bar",
        "RegistryProviderName": "MY-PROVIDER-NAME",
        "RegistryProviderEnvironment": "prod",
        "ConsumerId": "asdffdaew-dsa8-1245-n324-asdf893asdf893",
        "EnableRegionFeature1": false,
        "FetchDeltaUpdates": false,
        "FooRegistryEndpointTimeout": 60,
        "GatewayClassification": 42,
        "ProviderClassificationEnabled": true,
        "EnableSidecarRequestHook": false,
        "EnableSidecarResponseHook": true,
        "SidecarRoutingConfigIntervalSecs": 300,
        "SidecarKeepAliveSecs": 60,
        "EnableBlockingOfSomeThings": true,
        "DummyFeatureList": 14,
        "RedisClusterEnabled": false,
        "RedisClusterNodes": 15,
        "RedisReadFromReplicas": true,
        "RedisNumberOfRetries": 3,
        "RedisRetryFactor": 2,
        "RedisRetryExponent": 10,
        "RedisMaxRetryWait": 100,
         "RedisMinRetryWait": 10,
        "RedisEnableTlsMode": false,
        "PropertyPathPrefix": "/etc/foo/bar/baz/company/SOMETHING/my-service"
    });
}