✅ Weird ASP0016 behavior

Is there a semantic difference between these two pieces of code? the first one is fine, but the second one gives me

ASP0016

ASP0016

(which i don't think is correct? it's late and i'm kind of an asp noob so i might be mistaken...). the only difference is that the lambda for

atomLinks.Select

atomLinks.Select

has

async/await

async/await

in the first one, but not in the second.

Code 1, async/await, no warning

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            async (link) => await Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            async (link) => await Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

Code 2, no async/await, gives ASP0016

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            (link) => Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            (link) => Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

(weirdly, the warning also goes away if i eta-reduce the lambda into just the

Utils.GetFeedAsync

Utils.GetFeedAsync

method group/name)

(also:

Compiler version: '5.0.0-2.25472.11 (b48cd5e8)'. Language version: 13.0.

Compiler version: '5.0.0-2.25472.11 (b48cd5e8)'. Language version: 13.0.

just in case)

ASP0016: Do not return a value from RequestDelegate

Learn about analysis rule ASP0016: Do not return a value from RequestDelegate

✅ Weird ASP0016 behavior

Is there a semantic difference between these two pieces of code? the first one is fine, but the second one gives me

ASP0016

ASP0016

(which i don't think is correct? it's late and i'm kind of an asp noob so i might be mistaken...). the only difference is that the lambda for

atomLinks.Select

atomLinks.Select

has

async/await

async/await

in the first one, but not in the second.

Code 1, async/await, no warning

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            async (link) => await Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            async (link) => await Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

Code 2, no async/await, gives ASP0016

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            (link) => Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

app.MapGet("/molecule.xml", async context => {
    var atoms = await Task.WhenAll(
        atomLinks.Select(
            (link) => Utils.GetFeedAsync(link)
        )
    );
    var molecule = Utils.Aggregate(atoms);

    context.Response.ContentType = "application/atom+xml";
    using var bodyXmlWriter = XmlWriter.Create(context.Response.Body);
    molecule.SaveAsAtom10(bodyXmlWriter);
})

(weirdly, the warning also goes away if i eta-reduce the lambda into just the

Utils.GetFeedAsync

Utils.GetFeedAsync

method group/name)

(also:

Compiler version: '5.0.0-2.25472.11 (b48cd5e8)'. Language version: 13.0.

Compiler version: '5.0.0-2.25472.11 (b48cd5e8)'. Language version: 13.0.

just in case)

ASP0016: Do not return a value from RequestDelegate

Learn about analysis rule ASP0016: Do not return a value from RequestDelegate

✅ Weird ASP0016 behavior

✅ Weird ASP0016 behavior

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