Add support for custom overload names to the WinMD generator - #2454
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Port custom overload name support from PR #2275 (CsWinRT 2.x) to the CsWinRT 3.0 WinMD generator (cswinrtwinmdgen). When an authored method carries [Windows.Foundation.Metadata.Overload("Name")], emit that name in the generated .winmd instead of an auto-generated sequential one. windows-rs consumers require explicit overload names because Rust has no method overloading. - Record author-specified overload names while emitting interface methods and honor them in AddOverloadAttributesForType; stop copying the [Overload] attribute verbatim so it is never duplicated. - Select the default overload (which keeps the original name) from the [DefaultOverload] attribute rather than metadata order, so an author-specified name is not dropped when the default is not declared first. - Auto-generated names skip any name already used by another method or an author-specified overload, avoiding collisions. - Emit [Overload] only on interfaces (authored and synthesized), matching the Windows Runtime metadata convention; runtime classes expose their ABI through interfaces (consistent with CsWinRT 2.x). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Add the ICustomOverloadNames interface and CustomOverloadNamesClass authoring types, and the CustomOverloadNames consumption test. The test validates that author-specified [Overload] names (LookupByIndex, LookupByFlag, TransformNumber) appear in the generated projection's ABI vtables, on both an authored interface and a class's synthesized interface. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
…lt selection
Extend the overload-name tests to cover behaviors beyond the original PR:
- Verify the auto-generated ABI name (Transform2) coexists with an author-
specified one (TransformNumber) in the same overload group.
- OverloadCollisionClass: an author-specified overload name matching the auto
pattern ("M2") forces the auto-generated name of the remaining overload to
skip it ("M3").
- DefaultOverloadNotFirstClass / IDefaultOverloadNotFirst: [DefaultOverload] on
a non-first overload keeps the original ABI name, while the author-specified
name ("GetByIndex") on the first overload is still honored.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
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The custom overload names change (#2454) took error ids 0011 and 0012 for 'WindowsSdkNotFound' and 'CannotReadWindowsSdkXml', so renumber the new by-reference array/span parameter errors to 0013 and 0014 and update the tests and the testing skill accordingly. Also update the new test project for the build changes on staging: drop 'LangVersion' (now centralized in 'src/Directory.Build.props') and drop the removed 'ARM' platform from the solution entry (#2472, #2489). Finally, fix the stale 'GlobalPropertiesToRemove' mention in the testing skill, which the project file replaced with 'UndefineProperties'. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 8ec1fee3-01c2-4213-baf0-bed82d056068
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The range was already stale at '0001'-'0010': the custom overload names change (#2454) added 0011 and 0012. This adds 0013 and 0014, so bump the documented range to '0001'-'0014'. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 8ec1fee3-01c2-4213-baf0-bed82d056068
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… tests (#2443) * Fix custom-modifier type erasure in the WinMD generator type mapping MapTypeSignatureToOutput had no handling for CustomModifierTypeSignature, so any modifier-wrapped type fell through to the 'System.Object' fallback and was silently erased. This affects 'in' parameters on abstract/virtual/interface/delegate members, where the C# compiler emits a 'modreq(InAttribute)' on the by-reference type. For example, a COM interop 'in Guid riid' was emitted as '[in] object' instead of '[in] Guid&'. Strip leading custom modifiers before dispatching on the underlying type. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Validate unsupported array/span parameter conventions in the WinMD generator Windows Runtime arrays use one of three conventions (ReadOnlySpan<T> for PassArray, Span<T> for FillArray, or 'out T[]' for ReceiveArray), and spans are always passed by value. The generator previously emitted invalid metadata for a few shapes: 'ref T[]'/'in T[]' became '[in] T[]&', and 'out Span<T>'/'out ReadOnlySpan<T>' became a ReceiveArray. Reject these with clear errors (CSWINRTWINMDGEN0011 for by-reference arrays, CSWINRTWINMDGEN0012 for by-reference spans), while preserving the deliberate COM interop 'ref'/'in' scalar behavior (e.g. 'ref Guid riid' -> '[in]') and the by-value array PassArray default. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add WinMD generator parameter-convention failure tests Add a WinMDGeneratorTest project that runs the actual cswinrtwinmdgen tool end-to-end: it compiles small C# inputs with Roslyn, invokes the generator as a subprocess, and asserts a non-zero exit code plus the expected CSWINRTWINMDGEN error. The project deliberately focuses on failure cases (unsupported 'ref'/'in' arrays and 'out' spans), which can be exercised here without failing the build; the supported '.winmd' shapes (PassArray/FillArray/ReceiveArray) are covered by the authoring tests. The generator exposes no internals to the test project. Registers the project in the solution. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add WinMD generator invocation and invalid-input failure tests Extend the WinMDGeneratorTest harness with a custom-response-file overload and a public CompileComponent helper, then add Test_InvalidInputs covering the generator's remaining end-to-end failure modes: a missing response file (CSWINRTWINMDGEN0001), a malformed or duplicate-argument response file (0002), a missing required or unparseable argument (0003), a missing or corrupt input assembly (0004), an unwritable output path (0006), and a missing debug-repro directory (0008). Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Move WinMD generator TypeSignature helpers into an extension file Move StripCustomModifiers (previously a private method in WinMDWriter.TypeMapping) and the span predicates into a new Extensions/TypeSignatureExtensions.cs, matching the existing TypeDefinitionExtensions pattern. Rename IsSpan/IsReadOnlySpan to IsTypeOfSpan/IsTypeOfReadOnlySpan as extension methods, consistent with the interop generator's IsTypeOf* extensions. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Add AssertSuccess/AssertFailure helpers to collapse WinMD generator tests Rename the test helper to WinMDGeneratorRunner and give it AssertSuccess/AssertFailure entry points that run the generator and make the exit-code and error-output assertions, so each test is a single call. The run mechanics (Run, RunTool, GetGeneratorPath, the failure-result assertion, cleanup) are private; only the assertion entry points and CompileComponent (used by the response-file factory scenarios) are public. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Take full response file content as a single string in WinMD generator tests Change the AssertFailure response-file factory from Func<string, IReadOnlyList<string>> to Func<string, string> so callers provide the entire '.rsp' content as one multiline raw interpolated string instead of a list of per-line expressions. The runner now writes the content verbatim with File.WriteAllText. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Document the WinMDGeneratorTest project in the testing skill Add a 'WinMD generator tests' section describing the new src/Tests/WinMDGeneratorTest project (end-to-end failure-case tests for cswinrtwinmdgen), add a routing-table row, and bump the primary test area count to 6. Also add a matching per-project verification step to the update-testing-instructions skill and renumber the subsequent steps. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Fix stale comment in WinMDGeneratorTest project file The tests run the generator tool end-to-end as a subprocess rather than exercising its managed logic in-process, so update the comment that justifies 'CsWinRTEnabled=false' to match. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Move new WinMD generator errors after the existing ones Define the by-reference array/span parameter errors (0011/0012) after the debug-repro errors (0008-0010) instead of in the middle, so the methods appear in ascending error-id order. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Build the WinMD generator framework-dependent in the test project (NETSDK1151) The generator's PublishAot build is self-contained, which a non self-contained executable cannot reference (NETSDK1151). Replace GlobalPropertiesToRemove for RuntimeIdentifier with UndefineProperties for BuildToolArch, PublishBuildTool, RuntimeIdentifier and SelfContained so the tool is built framework-dependent for the build host, matching the proven WinRT.Internal reference pattern. The output stays under net10.0 (no RID subfolder), so the tool path used by the tests is unchanged. Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> * Wrap long exception messages for readability Split long interpolated exception message strings into multi-line concatenated strings in src/WinRT.WinMD.Generator/Errors/WellKnownWinMDExceptions.cs (ByReferenceArrayParameterNotSupported and ByReferenceSpanParameterNotSupported) to improve readability and line-length compliance; no functional behavior changes. * Adapt the WinMD generator parameter validation to staging/3.0 The custom overload names change (#2454) took error ids 0011 and 0012 for 'WindowsSdkNotFound' and 'CannotReadWindowsSdkXml', so renumber the new by-reference array/span parameter errors to 0013 and 0014 and update the tests and the testing skill accordingly. Also update the new test project for the build changes on staging: drop 'LangVersion' (now centralized in 'src/Directory.Build.props') and drop the removed 'ARM' platform from the solution entry (#2472, #2489). Finally, fix the stale 'GlobalPropertiesToRemove' mention in the testing skill, which the project file replaced with 'UndefineProperties'. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 8ec1fee3-01c2-4213-baf0-bed82d056068 * Update the WinMD generator error id range in the instructions The range was already stale at '0001'-'0010': the custom overload names change (#2454) added 0011 and 0012. This adds 0013 and 0014, so bump the documented range to '0001'-'0014'. Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com> Copilot-Session: 8ec1fee3-01c2-4213-baf0-bed82d056068 --------- Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com> Copilot-Session: 8ec1fee3-01c2-4213-baf0-bed82d056068
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Summary
Honor an author-applied
[Windows.Foundation.Metadata.Overload("Name")]attribute when generating a component's.winmd, emitting that name instead of an auto-generated sequential one. This ports #2275 (which targeted CsWinRT 2.x) to the CsWinRT 3.0 WinMD generator.Motivation
Rust (windows-rs) and some other Windows Runtime consumers cannot represent overloaded methods, so they rely on the
[Overload]attribute to give each overload a distinct, ergonomic ABI name. Previously, author-specified names were ignored and the generator always auto-generated sequential suffixes (Method2,Method3, …). PR #2275 added support for honoring them in CsWinRT 2.x. CsWinRT 3.0 produces the.winmdwith a different, post-build tool (cswinrtwinmdgen, which analyzes the compiled.dllwith AsmResolver rather than running a Roslyn source generator), so the behavior had to be re-implemented there.Changes
Generator (
src/WinRT.WinMD.Generator/):Writers/WinMDWriter.Finalization.cs:AddOverloadAttributesForTypenow honors an author-specified[Overload("...")]name when present (otherwise it keeps auto-generating a sequential name). It also selects the default overload (the one that keeps the original ABI name) from the[DefaultOverload]attribute rather than from metadata order, so an author-specified name is not dropped when the default is not declared first, and auto-generated names skip any name already used by another member or overload to avoid collisions. Adds theRecordUserSpecifiedOverloadNameandHasDefaultOverloadAttributehelpers.Writers/WinMDWriter.Members.cs: records the author-specified overload name while emitting interface methods (authored and synthesized), so finalization can honor it.Writers/WinMDWriter.Attributes.cs:ShouldCopyAttributeno longer copies[Overload]verbatim; it is emitted exactly once by the overload phase as the single source of truth, preventing duplicates.Writers/WinMDWriter.cs: adds the_userSpecifiedOverloadNamesmap.[Overload]is emitted only on interfaces (authored and synthesized), not on runtime classes, matching the Windows Runtime metadata convention and CsWinRT 2.x (a runtime class exposes its ABI through interfaces).Tests:
src/Tests/AuthoringTest/Program.cs: theICustomOverloadNamesinterface andCustomOverloadNamesClassfrom PR Add support for custom overload names to CsWinMD #2275, plus types covering additional behaviors (OverloadCollisionClass,IDefaultOverloadNotFirst/DefaultOverloadNotFirstClass).src/Tests/AuthoringConsumptionTest/test.cpp: the portedCustomOverloadNamesconsumption test, plus new tests for an auto-generated name coexisting with an author-specified one, collision avoidance, and[DefaultOverload]on a non-first overload.src/Tests/AuthoringConsumptionTest/AuthoringConsumptionTest.exe.manifest:activatableClassentries for the newly activatable test classes (includingCustomOverloadNamesClass, whose entry the original PR omitted).