Fix silently empty coverage for shared-framework assemblies missing from compileLibraries - #2032
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Bertk merged 1 commit intoSep 22, 2026
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…rom compileLibraries TryWithCustomResolverOnDotNetCore in CecilAssemblyResolver only resolves assemblies by looking them up in DependencyContext.CompileLibraries (built from the instrumented module's *.deps.json). Starting with the .NET SDK 10.0.4xx feature band, transitively shared Microsoft.Extensions.* assemblies (e.g. Microsoft.Extensions.Logging, referenced only via a transitive FrameworkReference to Microsoft.AspNetCore.App, not directly on the instrumented project) are no longer enumerated in compileLibraries at all. When a method has a default parameter of such a shared-framework enum type, Cecil's resolver misses it and throws CecilAssemblyResolutionException while instrumenting -- and that failure silently drops the entire module out of the coverage report (coverage.cobertura.xml ends up with an empty <packages/>) even though `dotnet test` itself is green, with no diagnostic pointing at the real cause. NetCoreSharedFrameworkResolver already exists in the same file and can resolve these assemblies directly from the shared-framework directory via runtimeconfig.json, but it was only ever consulted as a constructor fallback, never re-tried when the compileLibraries lookup specifically misses by name. This change adds that fallback: on a compileLibraries miss, ask NetCoreSharedFrameworkResolver directly before giving up. Verified against a live repro matching the reporter's stack trace (CecilAssemblyResolutionException -> Mono.Cecil.MetadataBuilder.GetConstantType) on dotnet SDK 10.0.400/10.0.401 (the same feature band as the report). Added TestInstrument_NetstandardAwareAssemblyResolver_MissingFromCompileLibrariesFallsBackToSharedFramework, modeled on the neighboring _SiblingRuntimeConfigCanResolveSharedFrameworkAssembly test: a module with no adjacent .deps.json forces the compileLibraries lookup to miss, and the test asserts System.Text.Json still resolves via NetCoreSharedFrameworkResolver. 5/5 green on net10.0 (net8.0 leg not run in this environment: the SDK image only ships the 10.0.11 runtime, an environment gap, not a test issue). Fixes coverlet-coverage#2026 Signed-off-by: Eljees <3.14hell@gmail.com>
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Bertk
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Bertk
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What
TryWithCustomResolverOnDotNetCoreinCecilAssemblyResolveronly resolves assemblies bylooking them up in
DependencyContext.CompileLibraries(built from the instrumentedmodule's
*.deps.json). Starting with the .NET SDK 10.0.4xx feature band, transitivelyshared
Microsoft.Extensions.*assemblies (e.g.Microsoft.Extensions.Logging,referenced only via a transitive
FrameworkReferencetoMicrosoft.AspNetCore.App, notdirectly on the instrumented project) are no longer enumerated in
compileLibrariesatall.
When a method has a default parameter of such a shared-framework enum type, Cecil's
resolver misses it and throws
CecilAssemblyResolutionExceptionwhile instrumenting —and that failure silently drops the entire module out of the coverage report
(
coverage.cobertura.xmlends up with an empty<packages/>) even thoughdotnet testitself is green, with no diagnostic pointing at the real cause.
NetCoreSharedFrameworkResolveralready exists in the same file and can resolve theseassemblies directly from the shared-framework directory via
runtimeconfig.json, but itwas only ever consulted as a constructor fallback, never re-tried when the
compileLibrarieslookup specifically misses by name. This PR adds that fallback: on acompileLibrariesmiss, askNetCoreSharedFrameworkResolverdirectly before giving up.Testing
Verified against a live repro matching the reporter's stack trace
(
CecilAssemblyResolutionException→Mono.Cecil.MetadataBuilder.GetConstantType) ondotnet SDK 10.0.400/10.0.401 (the same feature band as the report).
Added
TestInstrument_NetstandardAwareAssemblyResolver_MissingFromCompileLibrariesFallsBackToSharedFramework,modeled on the neighboring
..._SiblingRuntimeConfigCanResolveSharedFrameworkAssemblytest: a module with no adjacent
.deps.jsonforces thecompileLibrarieslookup to miss,and the test asserts
System.Text.Jsonstill resolves viaNetCoreSharedFrameworkResolver.5/5 green on net10.0 (net8.0 leg not run in this environment — the SDK image only ships
the 10.0.11 runtime, an environment gap, not a test issue).
Fixes #2026