Package reusable cDAC usage graph analyzer

[max-charlamb]

Summary

• package the existing cDAC usage graph analyzer for reuse by other repositories
• replace the CoreCLR-specific analysis entry point with configurable project and registration inputs
• support contract registrations that return default-valued struct implementations
• update the runtime CLI and usage tests to use the configurable analysis options

Testing

• CdacUsageGraph.Tests (85 passed)
• Microsoft.Diagnostics.DataContractReader.Usage.Tests (4 passed)
• regenerated cDAC contract documentation (no changes)

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[Copilot]

Pull request overview

This PR packages the existing cDAC usage graph analyzer for reuse by making its analysis entrypoints configurable (contracts project path + registration type), updating the CLI and tests accordingly, and expanding registration discovery to cover default-valued struct registrations.

Changes:

• Replace the CoreCLR-rooted analysis entrypoint with UsageGraphAnalysisOptions (project path, registration type name, source root, optional output directory).
• Update the CLI pipeline and tests to use the configurable analysis options and project-loading APIs.
• Extend contract registration discovery to recognize default(T) returns in registration factories.

Reviewed changes

Copilot reviewed 14 out of 14 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/native/managed/cdac/tools/CdacUsageGraph/tests/CdacUsageGraph.Tests/UsageWalkerIntegrationTests.cs	Updates integration test to run analysis via configurable options and explicit contracts project path.
src/native/managed/cdac/tools/CdacUsageGraph/tests/CdacUsageGraph.Tests/DataTypeIndexTests.cs	Updates parser call sites and adds a test covering default-valued struct registration discovery.
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/UsageGraphAnalyzer.cs	Introduces UsageGraphAnalysisOptions and updates public analyzer entrypoint to accept options.
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Docs/DocGenerator.cs	Minor descriptor-key parsing tweak (LastIndexOf('.')).
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Docs/DocDescriptorOverrides.cs	Minor descriptor-key validation tweak (LastIndexOf('.')).
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Docs/DocDescriptorMeanings.cs	Minor descriptor-key validation tweak (LastIndexOf('.')).
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Discovery/ContractRegistrationParser.cs	Makes registration discovery configurable and adds handling for default(T) returns.
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Compilation/CdacCompilationLoader.cs	Replaces root-based loading with explicit LoadProject(projectPath).
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Commands.cs	Updates CLI wiring to construct and pass UsageGraphAnalysisOptions.
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/CdacUsageGraph.csproj	Renames assembly, switches to $(CDacTfm), enables packing, and updates Roslyn package version properties.
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/AnalysisPipeline.cs	Refactors pipeline to use UsageGraphAnalysisOptions, including output-dir handling.
src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/AnalysisOptions.cs	Removes old CLI-only AnalysisOptions record in favor of shared analysis options.
src/native/managed/cdac/tests/UsageTests/UsageGraphFixture.cs	Updates usage tests to use UsageGraphAnalysisOptions with explicit project + registration type.
src/native/managed/cdac/tests/UsageTests/Microsoft.Diagnostics.DataContractReader.Usage.Tests.csproj	Removes JsonSerializerIsReflectionEnabledByDefault override from the test project.

[Copilot]

Pull request overview

Copilot reviewed 16 out of 16 changed files in this pull request and generated no new comments.

Suppressed comments (1)

src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Discovery/ContractRegistrationParser.cs:97

• The default-value registration path treats any default(T) as a concrete implementation and then assumes it can obtain a parameterless constructor. For reference types, default(T) is null (not an instance) and InstanceConstructors.Single(...) can throw if there is no parameterless ctor, so this can either mis-record registrations or crash analysis.

Restrict this path to value-type implementations (structs) and avoid Single throwing on unexpected shapes.

                    foreach (IDefaultValueOperation defaultValue in inv.Descendants().OfType<IDefaultValueOperation>())
                    {
                        if (defaultValue.Type is INamedTypeSymbol impl &&
                            comparer.Equals(impl.ContainingAssembly, compilation.Assembly) &&
                            compilation.IsAssignableTo(impl, iface) &&

[Copilot]

Pull request overview

Copilot reviewed 40 out of 40 changed files in this pull request and generated no new comments.

Suppressed comments (2)

src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/UsageGraphAnalyzer.cs:17

• This introduces new public API surface (UsageGraphAnalyzer.Analyze(UsageGraphAnalysisOptions) and UsageGraphAnalysisOptions). Per repo process, new public APIs need a linked issue with the api-approved label; if this isn’t yet approved, keep the API internal until the approval is in place.
  src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Discovery/ContractRegistrationParser.cs:97
• default(T) registrations can yield IDefaultValueOperation where Type is the interface itself (e.g., default(ITest)), which would make impl.InstanceConstructors.Single(...) throw (interfaces have no instance constructors). The default-value path should be constrained to value-type implementations (or otherwise ensure a parameterless ctor exists) before adding a registration.

[Copilot]

Pull request overview

Copilot reviewed 17 out of 17 changed files in this pull request and generated no new comments.

Suppressed comments (2)

src/native/managed/cdac/tests/UsageTests/Microsoft.Diagnostics.DataContractReader.Usage.Tests.csproj:6

• This project is the only cDAC test project that no longer disables reflection-based System.Text.Json serialization by default. Other cDAC projects keep JsonSerializerIsReflectionEnabledByDefault set to false (e.g. src/native/managed/cdac/tests/DumpTests/Microsoft.Diagnostics.DataContractReader.DumpTests.csproj:8). Consider restoring it here to keep the same runtime behavior/coverage across the cDAC test suite.

  <PropertyGroup>
    <TargetFramework>$(NetCoreAppToolCurrent)</TargetFramework>
    <Nullable>enable</Nullable>
    <IsTestProject>true</IsTestProject>
    <AssemblyName>Microsoft.Diagnostics.DataContractReader.Usage.Tests</AssemblyName>

src/native/managed/cdac/tools/CdacUsageGraph/src/CdacUsageGraph/Discovery/ContractRegistrationParser.cs:97

• The default-value registration discovery treats any default(T) found under a Register<IFace> invocation as an implementation type and then unconditionally calls impl.InstanceConstructors.Single(...). This can (1) incorrectly treat reference-type default(T) (which is null) as a registration and (2) throw if the default is target-typed to an interface/abstract type (no instance constructors). Restrict this path to value-type implementations and only add a registration when a parameterless ctor symbol is available.

                    foreach (IDefaultValueOperation defaultValue in inv.Descendants().OfType<IDefaultValueOperation>())
                    {
                        if (defaultValue.Type is INamedTypeSymbol impl &&
                            comparer.Equals(impl.ContainingAssembly, compilation.Assembly) &&
                            compilation.IsAssignableTo(impl, iface) &&
                            compilation.IsAssignableTo(impl, iContract))
                        {
                            registrations.Add(new ContractRegistration(
                                new ContractVersion(new ContractInterface(iface.Name), version),
                                iface,
                                impl,
                                impl.InstanceConstructors.Single(
                                    candidate => candidate.Parameters.Length == 0)));
                        }