#299 MappaDependencyInjectionAttribute

[sanelli]

Summary

• Add [MappaDependencyInjection] on a separate partial registrar class; the generator emits an IServiceCollection registration method for all same-assembly [Mappa] mappers.
• Configurable method name, extension vs instance, accessibility, service lifetime, InjectInterfaces (ClassOnly / InterfaceOnly / InterfaceAndClass), and IgnoreType.
• Diagnostics MP00070–MP00073 (non-partial, attribute conflict, no eligible interfaces, static mapper skipped); samples, AOT runner, and docs included.
• Version bumped to 10.2.0-alpha.48.

Test plan

• Generator integration tests (happy path + diagnostics including MP00073)
• Samples tests for RegisterMappaSamples
• AOT smoke runner for DI registrar
• .\Scripts\RunTestsAndReportCoverage.ps1 (line/branch slightly below step-1 baseline — see coverage note)

Coverage note

Final coverage vs issue baseline (98.4% / 90.6% / 100%): 98.3% / 90.3% / 100%. Remaining DI gaps are mostly defensive paths (GetDeclaredSymbol / null attribute data, inject-partial fallback) and shared AttributeDataExtensions helpers.

[github-actions]

Code coverage

Compared against the latest published coverage history from the code coverage gist.

Metric	Baseline	PR	Δ	Trend
Line	98.4%	98.3%	-0.1	▼
Branch	90.6%	90.3%	-0.3	▼
Method	100%	100%	0	=

No coverage metric dropped by more than 1 percentage point(s) versus baseline.

Benchmarks

AutoMapper is the BenchmarkDotNet ratio baseline. Absolute values are mean time in nanoseconds and allocated bytes. Ratio columns are competitor / Mappa as a percentage (n/a when either side is missing or Mappa is zero).

Benchmark	Automapper Mean (ns)	Automapper Allocated (B)	Mapster Mean (ns)	Mapster Allocated (B)	Mapperly Mean (ns)	Mapperly Allocated (B)	Mappa Mean (ns)	Mappa Allocated (B)	Automapper/Mappa Time	Automapper/Mappa Alloc	Mapperly/Mappa Time	Mapperly/Mappa Alloc	Mapster/Mappa Time	Mapster/Mappa Alloc
ArrayToListBenchmark	389150	592056.32	247810	648058.88	17020	128051.2	16930	128051.2	2298.6%	462.4%	100.5%	100%	1463.7%	506.1%
DictionaryBenchmark	399930	615014.4	282600	742277.12	31540	151019.52	39620	222218.24	1009.4%	276.8%	79.6%	68%	713.3%	334%
FastListToArrayBenchmark	387940	592025.6	242150	648028.16	16980	128020.48	19030	128020.48	2038.6%	462.4%	89.2%	100%	1272.5%	506.2%
IQueryableProjectionBenchmark	555700	67973.12	538000	67205.12	549900	69150.72	547900	69150.72	101.4%	98.3%	100.4%	100%	98.2%	97.2%
ListToArrayBenchmark	392020	592025.6	244740	648028.16	16890	128020.48	18050	128020.48	2171.9%	462.4%	93.6%	100%	1355.9%	506.2%
NestedDtoBenchmark	450010	742768.64	306160	789555.2	36060	149401.6	33090	157900.8	1360%	470.4%	109%	94.6%	925.2%	500%