Input-field @condition rewrap drops the enum leaf extraction

A @condition on an input field is resolved like any other condition and then rewrapped, so that the generated call reads its parameter values out of the enclosing argument’s map rather than off a top-level argument. ConditionResolver.rewrapForNested performs that rewrap by replacing each value parameter’s extraction with a CallSiteExtraction.NestedInputField, and it builds one through the two-argument convenience constructor, whose javadoc states that it defaults the leaf to Direct. The parameter’s own leaf transform is therefore discarded.

For every parameter this has ever been exercised on that leaf was already Direct, so nothing changed. It is not Direct for one population. ServiceCatalog.legacyArgExtraction, the only producer of a condition parameter’s extraction, returns EnumValueOf when the parameter’s declared Java type is an enum class, which is the jOOQ-generated enum a @condition method naturally takes (static Condition byRating(Film table, MpaaRating rating)). Written on a field argument, that method receives the enum. Written on an input field, the same method receives the wire string cast to the enum type, which is a ClassCastException at request time rather than a build failure.

Two things make this worth stating rather than merely fixing in place. The rewrap has been repaired once before for a neighbouring loss: the same method used to drop each parameter’s own path descent, so a dotted binding cast the whole wrapper map to the leaf type, and the repair appended the path tail without revisiting the leaf. And the loss is silent by construction on both occasions, because the extraction is replaced rather than composed; a rewrap that carried the existing extraction in as the leaf could not lose one, and the three-argument constructor already refuses the one leaf shape that would not compose (another NestedInputField).

Scope worth settling at Spec: whether the fix is simply passing arg.extraction() as the leaf, and what a regression test looks like at which tier. The execution tier is where a wrong cast surfaces, and the fixture needs a jOOQ enum column reachable from an input-field @condition.