Fix CancellationToken parameter ordering and name collision in v3 OperationCompiler

[Copilot]

Two bugs in the CT overload generation: CT was appended after optional parameters (invalid in .NET — required params must precede optional), and the CT parameter name was always cancellationToken with no collision check against generated OpenAPI parameter names.

Changes

• Parameter ordering: Split parameter building into two passes (required, then optional) with the used-name set threaded between them. CT is now inserted at ctArgIndex = requiredParamCount, giving the signature: (required...) → CT → (optional...).

• Name uniqueness: Collect all generated parameter names into a set before creating the CT param; fall back to cancellationToken1, cancellationToken2, etc. on collision.

• invokeCode extraction: CT is now extracted by List.item ctArgIndex allArgs (index captured during parameter building) rather than by peeling off the last argument, which broke under the new ordering.

Before / After signature example

// Before: CT appended last — after optional params
MyMethod(requiredA: string, ?optB: int, cancellationToken: CancellationToken)

// After: CT sits between required and optional
MyMethod(requiredA: string, cancellationToken: CancellationToken, ?optB: int)

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[sergey-tihon]

@copilot fix build

[Copilot]

@copilot fix build

Fixed in commit 6e5ba8a.

Root cause: dotnet build SwaggerProvider.sln triggers inner-build restores via Paket.Restore.targets that overwrite project.assets.json with only a single TFM (the last one processed — either netstandard2.0 or net10.0). When BuildTests then ran dotnet build SwaggerProvider.TestsAndDocs.sln, it hit NETSDK1005 because the assets file was missing the other TFM.

Fix: BuildTests now first runs dotnet restore SwaggerProvider.TestsAndDocs.sln (which correctly populates the assets file with both netstandard2.0 and net10.0), then builds with --no-restore to prevent the inner-build restore from corrupting the assets file again.

[sergey-tihon]

/repo-assist merge target branch into this one and actualize changes

[github-actions]

✅ Repo Assist completed successfully!

[sergey-tihon]

@copilot merge target repo-assist/feat-cancellationtoken-issue-212-2026-03-23-448c1cde90ec7d95 branch into this one, resolve conflicts and actualize changes

[Copilot]

@copilot merge target repo-assist/feat-cancellationtoken-issue-212-2026-03-23-448c1cde90ec7d95 branch into this one, resolve conflicts and actualize changes

Done in commit 4888df8. Merged repo-assist/feat-cancellationtoken-issue-212-2026-03-23-448c1cde90ec7d95 into this branch. The base branch had independently added CT name-uniqueness (via Seq.initInfinite), while this branch already had that plus the parameter ordering fix. Conflict in OperationCompiler.fs resolved by keeping our more complete implementation (two-pass buildProvidedParameters, ctArgIndex insertion between required and optional params).

[Copilot]

Pull request overview

This PR fixes v3 client-method generation in OperationCompiler so CancellationToken is emitted as a required parameter between required and optional OpenAPI parameters (valid .NET ordering), and ensures the generated CT parameter name cannot collide with OpenAPI parameter names. It also adjusts the build script to explicitly restore before building the test solution to avoid multi-TFM assets issues.

Changes:

• Reworked v3 parameter construction into required/optional passes and inserted CancellationToken at ctArgIndex = requiredParamCount.
• Added unique-name generation for the CT parameter (cancellationToken, cancellationToken1, …) based on already-generated parameter names.
• Updated invokeCode to extract CT by ctArgIndex rather than assuming it is the last argument; updated BuildTests to restore then build --no-restore.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
src/SwaggerProvider.DesignTime/v3/OperationCompiler.fs	Fixes CT parameter ordering and name-collision handling; updates invokeCode arg extraction accordingly.
build.fsx	Adds an explicit restore step before building the tests solution to stabilize multi-TFM restore/build behavior.

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[Copilot]

The CT ordering/name-collision fixes are not covered by tests. Consider adding a v3 unit test that compiles a minimal schema with both required and optional parameters and asserts (via reflection over the provided method) that the CancellationToken parameter is positioned after required params and before optional params, and another schema containing an OpenAPI parameter named cancellationToken to assert the generated CT parameter name is suffixed (e.g., cancellationToken1).