Add type provider integration tests for CancellationToken-overloaded methods by Copilot · Pull Request #338 · fsprojects/SwaggerProvider

Copilot · 2026-03-23T20:18:06Z

The CancellationToken PR lacked integration tests that exercise the TP-generated CT overloads end-to-end against a real HTTP server.

Changes

v3/Swashbuckle.CancellationToken.Tests.fs — new test module with 4 [<Fact>] tests calling TP-generated methods with explicit CT arguments:
- CancellationToken.None on GET and POST operations
- Active CancellationTokenSource token (happy path)
- Pre-cancelled token → asserts OperationCanceledException
SwaggerProvider.ProviderTests.fsproj — includes the new file, ordered after Swashbuckle.ReturnControllers.Tests.fs (which defines the api instance these tests reuse)

// Explicit CancellationToken.None
let! result = api.GetApiReturnBoolean(CancellationToken.None)

// Active token
use cts = new CancellationTokenSource()
let! result = api.GetApiReturnInt32(cts.Token)

// Pre-cancelled → OperationCanceledException
use cts = new CancellationTokenSource()
cts.Cancel()
let! _ = api.GetApiReturnString(cts.Token)  // throws

✨ Let Copilot coding agent set things up for you — coding agent works faster and does higher quality work when set up for your repo.

Co-authored-by: sergey-tihon <1197905+sergey-tihon@users.noreply.github.com> Agent-Logs-Url: https://github.com/fsprojects/SwaggerProvider/sessions/8363d577-d359-47b3-ae35-5f9003978db0

Copilot · 2026-03-23T20:47:49Z

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

petstore.swagger.io
- Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet /usr/share/dotnet/sdk/10.0.102/FSharp/fsc.dll @/tmp/MSBuildTempiXPNHK/tmpa0d7dc1fc7d0470caabd2d412b9e0d9f.rsp git conf�� --local credential.helper (dns block)
- Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet /usr/share/dotnet/sdk/10.0.102/FSharp/fsc.dll @/tmp/MSBuildTempRgGS22/tmp88efa443e8d448f99de291eeff3ced7b.rsp git ogs.�� linuxagent-logcollector.slice (dns block)
- Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet /usr/share/dotnet/sdk/10.0.102/FSharp/fsc.dll @/tmp/MSBuildTempL58rKC/tmp5f8b101f8b714b81aff5ebcb17be25ae.rsp bash --no�� --noprofile (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

Configure Actions setup steps to set up my environment, which run before the firewall is enabled
Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

sergey-tihon · 2026-03-23T20:55:17Z

@copilot ci still failing

… invalid IL for structs Co-authored-by: sergey-tihon <1197905+sergey-tihon@users.noreply.github.com> Agent-Logs-Url: https://github.com/fsprojects/SwaggerProvider/sessions/cd02aac9-3f51-40c9-af2f-11d1eda31d77

Copilot · 2026-03-23T21:08:02Z

@copilot ci still failing

Fixed in e74b3e2. Root cause: Expr.Coerce(expr, typeof<CancellationToken>) generates a castclass IL instruction which is only valid for reference types — CancellationToken is a struct, so the JIT rejected it with InvalidProgramException.

Fix: extract the CT argument by position (always the last parameter in the overload) and use Expr.Cast<Threading.CancellationToken>(ctArg) which is a typed wrapper with no IL cast instruction. Also replaced the fragile sVar.Name = "cancellationToken" check that could collide with OpenAPI spec parameters of the same name.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

petstore.swagger.io
- Triggering command: /usr/share/dotnet/dotnet /usr/share/dotnet/dotnet /usr/share/dotnet/sdk/10.0.102/FSharp/fsc.dll @/tmp/MSBuildTemppJyfcF/tmpf860966a85c0444d9d34ff83f7d6577f.rsp (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

Configure Actions setup steps to set up my environment, which run before the firewall is enabled
Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)

Copilot

Pull request overview

Adds end-to-end integration coverage for type-provider-generated CancellationToken overloads against the existing Swashbuckle test server, and updates the v3 operation invocation compiler to reliably extract the CT argument.

Changes:

Add new v3 integration tests that call TP-generated methods with explicit CancellationToken arguments (including pre-cancelled token behavior).
Register the new test module in the provider test project with correct compile ordering.
Adjust v3 OperationCompiler to extract CancellationToken by argument position (last argument) instead of by name.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
tests/SwaggerProvider.ProviderTests/v3/Swashbuckle.CancellationToken.Tests.fs	New integration tests exercising CT overloads (GET/POST, active token, pre-cancelled token).
tests/SwaggerProvider.ProviderTests/SwaggerProvider.ProviderTests.fsproj	Includes the new test file after `Swashbuckle.ReturnControllers.Tests.fs` to reuse `api`.
src/SwaggerProvider.DesignTime/v3/OperationCompiler.fs	Changes CT extraction in provided method invoke code to be position-based and avoid prior name/cast issues.

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

Copilot · 2026-03-23T21:30:57Z

src/SwaggerProvider.DesignTime/v3/OperationCompiler.fs

+                        // When the CancellationToken overload is generated, CancellationToken is always appended last.
+                        // Extract it by position to avoid name-collision issues and invalid Expr.Coerce
+                        // on a struct type (which generates an invalid castclass IL instruction).
+                        let apiArgs, ct =
+                            let allArgs = List.tail args // skip `this`
+
+                            if includeCancellationToken then
+                                match List.rev allArgs with
+                                | ctArg :: revApiArgs -> List.rev revApiArgs, Expr.Cast<Threading.CancellationToken>(ctArg)
+                                | [] -> failwith "Expected CancellationToken argument but argument list was empty"
+                            else
+                                allArgs, <@ Threading.CancellationToken.None @>


The PR title/description focuses on adding integration tests, but this hunk also changes type provider code generation behavior (CancellationToken argument extraction). Please update the PR description/title to reflect the compiler change (or split into a separate PR) so reviewers don’t miss the functional impact.

Copilot · 2026-03-23T21:30:57Z

src/SwaggerProvider.DesignTime/v3/OperationCompiler.fs

+                            if includeCancellationToken then
+                                match List.rev allArgs with
+                                | ctArg :: revApiArgs -> List.rev revApiArgs, Expr.Cast<Threading.CancellationToken>(ctArg)
+                                | [] -> failwith "Expected CancellationToken argument but argument list was empty"


This failwith message is likely only hit when TP invocation arguments are unexpected, but it would be much easier to diagnose if it included the operation/method name (e.g., providedMethodName) and the received argument count. Consider switching to failwithf with that context.

Suggested change

| [] -> failwith "Expected CancellationToken argument but argument list was empty"

| [] ->

failwithf

"Method '%s' expected a CancellationToken argument as the last parameter but received %d argument(s)."

providedMethodName

allArgs.Length

Initial plan

d53831c

Copilot AI assigned Copilot and sergey-tihon Mar 23, 2026

Copilot AI mentioned this pull request Mar 23, 2026

[Repo Assist] feat: add CancellationToken support to OpenApiClientProvider generated methods (closes #212) #336

Open

Copilot started work on behalf of sergey-tihon March 23, 2026 20:18 View session

feat: add type provider integration tests for CancellationToken support

4d6cc06

Co-authored-by: sergey-tihon <1197905+sergey-tihon@users.noreply.github.com> Agent-Logs-Url: https://github.com/fsprojects/SwaggerProvider/sessions/8363d577-d359-47b3-ae35-5f9003978db0

Copilot AI changed the title ~~[WIP] Add CancellationToken support to OpenApiClientProvider generated methods~~ Add type provider integration tests for CancellationToken-overloaded methods Mar 23, 2026

Copilot AI requested a review from sergey-tihon March 23, 2026 20:47

Copilot finished work on behalf of sergey-tihon March 23, 2026 20:47

Copilot started work on behalf of sergey-tihon March 23, 2026 20:55 View session

fix: use Expr.Cast (not Expr.Coerce) for CancellationToken to prevent…

e74b3e2

… invalid IL for structs Co-authored-by: sergey-tihon <1197905+sergey-tihon@users.noreply.github.com> Agent-Logs-Url: https://github.com/fsprojects/SwaggerProvider/sessions/cd02aac9-3f51-40c9-af2f-11d1eda31d77

Copilot finished work on behalf of sergey-tihon March 23, 2026 21:08

sergey-tihon marked this pull request as ready for review March 23, 2026 21:27

Copilot AI review requested due to automatic review settings March 23, 2026 21:27

Copilot started reviewing on behalf of sergey-tihon March 23, 2026 21:27 View session

Copilot AI reviewed Mar 23, 2026

View reviewed changes

sergey-tihon merged commit b2f0d80 into repo-assist/feat-cancellationtoken-issue-212-2026-03-23-448c1cde90ec7d95 Mar 23, 2026
18 checks passed

sergey-tihon deleted the copilot/sub-pr-336 branch March 23, 2026 22:12

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Add type provider integration tests for CancellationToken-overloaded methods#338

Add type provider integration tests for CancellationToken-overloaded methods#338
sergey-tihon merged 3 commits intorepo-assist/feat-cancellationtoken-issue-212-2026-03-23-448c1cde90ec7d95from
copilot/sub-pr-336

Copilot AI commented Mar 23, 2026 •

edited

Loading

Uh oh!

Copilot AI commented Mar 23, 2026

I tried to connect to the following addresses, but was blocked by firewall rules:

Uh oh!

sergey-tihon commented Mar 23, 2026

Uh oh!

Copilot AI commented Mar 23, 2026 •

edited

Loading

I tried to connect to the following addresses, but was blocked by firewall rules:

Uh oh!

Copilot AI left a comment

Uh oh!

Copilot AI Mar 23, 2026

Uh oh!

Copilot AI Mar 23, 2026

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

-                                | [] -> failwith "Expected CancellationToken argument but argument list was empty"
+                                | [] ->
+                                    failwithf
+                                        "Method '%s' expected a CancellationToken argument as the last parameter but received %d argument(s)."
+                                        providedMethodName
+                                        allArgs.Length

Conversation

Copilot AI commented Mar 23, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Changes

Uh oh!

Copilot AI commented Mar 23, 2026

I tried to connect to the following addresses, but was blocked by firewall rules:

Uh oh!

sergey-tihon commented Mar 23, 2026

Uh oh!

Copilot AI commented Mar 23, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

I tried to connect to the following addresses, but was blocked by firewall rules:

Uh oh!

Copilot AI left a comment

Choose a reason for hiding this comment

Pull request overview

Reviewed changes

Uh oh!

Copilot AI Mar 23, 2026

Choose a reason for hiding this comment

Uh oh!

Copilot AI Mar 23, 2026

Choose a reason for hiding this comment

Uh oh!

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

3 participants

Copilot AI commented Mar 23, 2026 •

edited

Loading

Copilot AI commented Mar 23, 2026 •

edited

Loading