Parallel execution of mutations

Is there an existing issue for this?

• I have searched the existing issues

Product

Hot Chocolate

Describe the bug

Mutations in v13 are executed in paralled, whil GraphQL specification clearly states: https://graphql.org/learn/queries/#multiple-fields-in-mutations

While query fields are executed in parallel, mutation fields run in series, one after the other.

Steps to reproduce

Here is a minimal reproducible example.

GraphQL:

mutation {
  a: do
  b: do
}

Code:

var builder = WebApplication.CreateBuilder(args);
builder.Services.AddGraphQLServer()
    .AddQueryType<Queries>()
    .AddMutationType<Mutations>();
var app = builder.Build();

app.MapGraphQL();
app.Run();

public class Mutations
{
    private readonly ILogger<Mutations> _logger;

    public Mutations(ILogger<Mutations> logger)
    {
        _logger = logger;
    }

    public async Task<bool> Do()
    {
        _logger.LogWarning("BEGIN");
        await Task.Delay(100);
        _logger.LogError("/END");
        return true;
    }
}

public class Queries
{
    private readonly ILogger<Queries> _logger;

    public Queries(ILogger<Queries> logger)
    {
        _logger = logger;
    }

    public async Task<bool> Get()
    {
        _logger.LogWarning("Q");
        await Task.Delay(100);
        _logger.LogError("/Q");
        return true;
    }
}

Relevant log output

Expected output:
BEGIN
/END
BEGIN
/END

Actual output:

BEGIN
BEGIN
/END
/END

Additional Context?

No response

Version

13.0.0

[michaelstaib]

I can confirm the issue. Still looking for the cause and why our test did not catch it.

[michaelstaib]

The issue is fixed now … we will issue a fix tonight. Thanks for reporting.