feat(parser): support “enter tapped this turn” (Due Respect, Nahiri’s Lithoforming)

[codevector96]

Summary

Implements the previously-unsupported "enter tapped this turn" replacement, so Due Respect ("Permanents enter tapped this turn. Draw a card.") and Nahiri's Lithoforming ("… Lands you control enter tapped this turn.") stop dropping that clause to Effect::Unimplemented.

The clause is a turn-duration floating replacement: on resolution it installs a global replacement that makes a filtered set of permanents enter the battlefield tapped, expiring at cleanup. It reuses the existing external "[objects] enter tapped" building block (the same ReplacementDefinition{ event: ChangeZone, execute: SetTapState{Tap} } shape that Authority of the Consuls already uses) — this is just its turn-scoped, spell-installed variant. No new engine surface: one new private parser function lifts the clause into the existing Effect::AddTargetReplacement { target: None } installer with an EndOfTurn expiry; the resolver, floating-replacement scan, controller-anchoring, and cleanup pruning are all unchanged.

Model: claude-opus-4-8
Tier: Frontier
Thinking: high

Implementation method (required)

• Produced via the /engine-implementer pipeline (plan → review-plan → implement → review-impl → commit)

Anchored on

• crates/engine/src/parser/oracle_effect/mod.rs — try_parse_global_damage_modification_replacement: the sibling that wraps a parse_replacement_line def in Effect::AddTargetReplacement { target: None, expiry: EndOfTurn }; the new function mirrors its shape (different seam: the pre-peel "this turn" scan block, since the duration is trailing).
• crates/engine/src/parser/oracle_replacement.rs — parse_external_enters_tapped / build_external_entry_replacement: the existing ChangeZone + SetTapState{SelfRef, Tap} builder reused as the detector.
• The existing scan_contains_phrase(&original_lower, "this turn") arms (try_parse_play_from_exile, try_parse_additional_land_this_turn): the new arm copies their peel_ctx optional/condition handling and attach_unless_slots return.

Gate A

scripts/check-parser-combinators.sh passes on the staged diff (no violations). The new detection delegates entirely to strip_trailing_duration + parse_replacement_line (nom end-to-end) plus a typed matches! shape guard — no string-method dispatch, match-arm string literals, chained if let Ok = tag(...), verbatim-sentence equality, or hand-built Effect::Unimplemented.

CR references

• CR 614.1d — "[Objects] enter [the battlefield] …" replacement effects (the external enters-tapped class; distinct from the self form in 614.1c).
• CR 514.2 — "this turn" effects end during cleanup (the EndOfTurn expiry).
• CR 611.2a — a resolution-fixed continuous effect (AddTargetReplacement { target: None }, controller anchored at install).
• CR 109.4 — controller-relative object references ("Lands you control").

Verification

Built and tested with cargo (this contributor box has no Tilt):

tests/enters_tapped_this_turn.rs ... 5 passed; 0 failed
engine --lib parser::oracle_effect ... 2496 passed; 0 failed

• New tests (crates/engine/tests/enters_tapped_this_turn.rs, typed fixtures, real cast/resolve pipeline): parser SHAPE for both cards (with a zero-Unimplemented reach-guard); a permanent entering after Due Respect resolves enters tapped while one that entered before is unaffected; the replacement expires at cleanup (later-turn entries untapped); and the load-bearing Nahiri multi-authority test — P0's land enters tapped while P1's land and P0's non-land do not (proving the source_controller + "Lands you control" filter).
• Fail-closed: any duration other than end-of-turn, or any non-ChangeZone/SetTapState shape, returns None and the clause stays Unimplemented — coverage flips to supported only for what's genuinely handled.

[gemini-code-assist]

Code Review

This pull request adds a new integration test suite in crates/engine/tests/enters_tapped_this_turn.rs to verify the parser shape and runtime behavior of turn-duration floating replacement effects, specifically testing cards like Due Respect and Nahiri's Lithoforming. The tests cover parsing verification, replacement execution, cleanup-phase expiry, and controller-scoped filtering. There are no review comments, and I have no feedback to provide.

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[github-actions]

Parse changes introduced by this PR · 2 card(s), 3 signature(s) (baseline: main 3d347a3fc7cf)

2 card(s) · ability/AddTargetReplacement · added: AddTargetReplacement (destination=Battlefield, event=ChangeZone, expiry=EndOfTurn)

Examples: Due Respect, Nahiri's Lithoforming

1 card(s) · ability/lands · removed: lands (duration=until end of turn)

Examples: Nahiri's Lithoforming

1 card(s) · ability/permanents · removed: permanents (duration=until end of turn)

Examples: Due Respect

2 card(s) had Oracle-text changes (errata/reprint) — excluded as non-parser.

[matthewevans]

Maintainer review: parser change is narrowly scoped, reuses the existing external-entry replacement parser and AddTargetReplacement resolver, has current parse-diff evidence for only Due Respect and Nahiri’s Lithoforming, and CI is green.