Match vanilla's default CommandBehavior: no SingleResult/SingleRow - #196
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The one-row and query paths hardcoded SingleResult (and SingleRow for First/FirstOrDefault), where vanilla Dapper strips both by default - Settings.UseSingleResultOptimization/UseSingleRowOptimization are opt-in, and the default exists for a reason: with those flags SqlClient cancels the remainder of the batch on close, silently discarding trailing errors, and the combination measured ~10x slower on the async one-row path. Found by the Dapper test suite (QueryFirst_PerformanceAndCorrectness): 'select *; raiserror(...)' produced no exception under Dapper.AOT while vanilla threw SqlException side-by-side on the same connection, and QueryFirstAsync over a wide result burned minutes. With SequentialAccess-only (vanilla's effective default): both sync and async error cases throw as vanilla does, and async-full drops 568ms to 57ms in the repro. If opt-in knobs are ever wanted they belong in SingleFlags, as noted there.
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* Start the Dapper/Dapper.AOT parity accounting under notes/ The goal on record: enable Dapper.AOT in the Dapper test suite, announce types via attributes, and have it swallow everything - AOT-clean. - parity.md: the feature table, with impact/complexity per gap (several 'gaps' score zero because the concept doesn't exist under AOT, e.g. the ref-emit plan cache) - tokens.md: @ids expansion, {=literal}, ?foo? pseudo-positional, param filtering - type-vs-generic.md: the announced-types design space for Type-based APIs - test-suite-audit.md: the Dapper tests as acceptance corpus, sequenced * GetTypeDeserializer is valid API, not cache plumbing With announced types it's the same dispatch map (boxed materializer), and its generic strengthening already exists as GetRowParser<T>. The real hole is the write side: CreateParamInfoGenerator has no generic counterpart - recorded the GetParameterBinder<T> proposal, and the question of blessing CommandFactory<T>/RowFactory<T> as the supported surface. ReadChar and friends are plain AOT-safe statics, nothing to do. * Scope the accounting to the public API and observable behavior PublicAPI.Shipped.txt is the checklist; the contract is what reaches the provider and what comes back, never Dapper's internals. Cuts both ways: the dynamic row needs behavioral fidelity only (the type is internal), while the public infrastructure statics ARE in scope because extenders call them. * Record the decision: internals-asserting tests get adjusted, not maintained * New work item: warn (new DAP id) on use of the has-no-meaning APIs Plan-cache surface, CommandFlags.NoCache, possibly ConnectionStringComparer: supported-and-meaningless under AOT, which is a different statement to DAP001's unsupported-but-meaningful. Warning, not error - the code runs. * Measurement caveat: build-time DAP counts are an upper bound Some failure modes are silent until executed - handled means intercepted, not correct. Only the DB-backed test run catches silent divergence. * First harness baseline: 'handled 396 of 396' alongside 96 compile errors Two root-cause generator bugs (array-of-anonymous parameter emits the display string and wrecks the parse; inaccessible row types are emitted rather than refused), plus two scorecard honesty problems (the denominator excludes unattempted APIs; handled does not mean compiles) and a zero- analyzer-diagnostics anomaly to re-check once the compile is clean. * Generator audit: the capture model snapshots Roslyn nodes; fix first Both generators' cached SourceState hold IMethodSymbol/ITypeSymbol/ Location (MemberMap even holds an IOperation), and the pipeline combines the raw CompilationProvider into the source output - so it behaves as a full-recompute generator with a memory leak. Recorded as a sequencing gate ahead of the gap-closing features, with the fix shape that worked for protobuf-net (plain equatable model, span-based locations, separate diagnostics branch, shape-enforcing test). * Record the agreed plan: gap table, then generator model, then features The line that resolves the phase-1/2 tension: nothing that adds parse-time state lands before the model rework completes; refusals and scorecard fixes are allowed ahead of it, which is what lets phase 1 see. * Round 2 numbers, and log the modern-interceptor-syntax work item * Round 3: the suite compiles with AOT enabled (4 fix PRs + 2 severity downgrades) * Scoreboard: all three TFM legs compile; local SQL Server available * Work item: [UnsafeAccessor] may lift the accessibility refusals (net8+) * Round 4: the honest scorecard says 53%, not 100% * Harvest the skip breakdown; flag the DAP016 corpus-shape decision * Round 5: first behavioral run - 84 failures, every one compiled clean * Note that aot-harness is deliberately local-only * Phase 2 log: approach and increments * Phase 2 log: increment 1 done * Phase 2 log: 3a done * Phase 2 log: 3b done * Phase 2 log: 3c-i done; two cached symbols remain * Phase 2 log: result-side plan done; one symbol left * Phase 2 log: cached model fully plain; only increment 4 remains * Phase 2 log: complete - PRs #187 + #188 * Phase 2 log: caching tests landed * Phase 2 log: readonly-field quirk fixed (#190) * Round 6: DAP051 + restructure takes interception to 68.1% * Round 6b: 612/760 behavioral; failures track interception growth honestly * DynamicParameters design: delegate to the bag; needs one small Dapper API * Round 7: DynamicParameters at 73.5%; First-pipeline drain divergence found * Round 7b: 612/762; every failure class maps to a planned feature * Interceptor-syntax migration: soft-target requirement recorded * Tokens: runtime-SQL design - per-factory memoized role scan * Record the feature-detection rule (DAP052) in the design note * Round 8: CommandBehavior parity fix (PR #196) * Round 8b: 616/762, suite loop 17s * Round 9: list expansion lands (PR #197), 638/762 * Round 10: custom parameters + the two bugs they uncovered, 658/793 * Round 11: dynamic-record fidelity, 672/793 * Sync with main; point parity rows at their open PRs The table lands on main via #186; from here each feature PR flips its own cells, so the table and the merge history cannot drift apart. Rows with an open PR say so, and the flip to a settled status is that PR's job.
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The one-row and query paths hardcoded
SingleResult(plusSingleRowfor First/FirstOrDefault), where vanilla strips both by default —Settings.UseSingleResultOptimization/UseSingleRowOptimizationare opt-in, and the default exists for a reason: with those flags SqlClient cancels the remainder of the batch on close, silently discarding trailing errors.Found by the Dapper test suite's
QueryFirst_PerformanceAndCorrectness, then pinned with a side-by-side repro on one connection:QueryFirst("select *; raiserror(...)")SqlExceptionSqlExceptionQueryFirstover 100k rows(The suite's 500k-row variant burned ~4.5 minutes per provider before.)
Fix:
SequentialAccessonly, i.e. vanilla's effective default. If opt-in optimization knobs are ever wanted, they belong inSingleFlags— noted in the comment there. Runtime-library change only; full unit suite green on net10.0/net48, goldens untouched.