Couldn't infer type parameter 'N extends Built<N, NB>'.

[Jorgezz]

error: Couldn't infer type parameter 'N extends Built<N, NB>'.

Tried to infer 'AppState' for 'N extends Built<N, NB>' which doesn't work:
Type parameter 'N extends Built<N, NB>' declared to extend 'Built<AppState, NB extends Builder<N, NB>>'.
The type 'AppState' was inferred from:
Parameter 'nested' declared as 'NestedReducerBuilder<AppState, AppStateBuilder, N, NB>'
but argument is 'NestedReducerBuilder<AppState, AppStateBuilder, AppState, AppStateBuilder>'.

Consider passing explicit type argument(s) to the generic.

(could_not_infer at [xxx] lib/engine/app_reducers.dart:35)

code:
final appReducerBuilder = ReducerBuilder<AppState, AppStateBuilder>()
..combineNested(aReducerBuilder) etc...

final debugReducerBuilder = NestedReducerBuilder<AppState, AppStateBuilder,
DebugState, DebugStateBuilder>((s) => s.debugState, (b) => b.debugState)
..add(DebugActionsNames.toggleShowPerformanceOverlayAction,
_toggleShowPerformanceOverlay)
..add(DebugActionsNames.toggleStaggeredTileUseFit,
_toggleStaggeredTileUseExtent)
..add(DebugActionsNames.toggleApiEnvironment, _toggleTestEnvironment)
..add(DebugActionsNames.toggleMotiveDetectorDebug, _toggleMotionDetectorDebug);

[davidmarne]

this appears to be a bug that got introduced to the analyzer in dart 2.5
there was an issue created here: dart-lang/sdk#38365