fix(parser): scope enchanted-creature's-controller phase triggers (#5275)

[philluiz2323]

Summary

[[Super Intelligence]] — "Enchant creature\nAt the beginning of the upkeep of enchanted creature's controller, that player draws a card." — behaved like a Howling Mine, giving the extra card on every player's upkeep instead of only the enchanted creature's controller's upkeep.

Root cause: try_parse_phase_trigger scopes "enchanted player's <phase>" (player-enchant Auras) to AttachedTo, but had no handling for the creature-enchant "the <phase> of enchanted creature's controller" form. That left valid_target unset, and match_phase treats an unset player scope as "any active player" — so the trigger fired on every upkeep.

Fixes #5275

Fix

Two small, localized changes — no new engine variant:

1. Parser (try_parse_phase_trigger): recognize "enchanted creature's controller" / "enchanted permanent's controller" (ASCII + ’) in the phase text and set valid_target = TargetFilter::ParentTargetController, mirroring the existing "enchanted player's" → AttachedTo arm.
2. Matcher (player_matches_filter, trigger side): add a ParentTargetController arm that resolves to the controller of the permanent the source Aura is attached to and compares it to the active player.

Per CR 303.4e, the Aura's controller and the enchanted permanent's controller need not be the same, so this can't reuse the source-controller turn constraint (OnlyDuringYourTurn). ParentTargetController's documented resolution already covers "the AttachedTo host on source for Aura phase triggers," so it's the intended representation here; no trigger currently used it as valid_target, so the new matcher arm is additive.

CR references

• CR 303.4e — an Aura's controller is separate from the enchanted object's controller; the two need not be the same
• CR 109.4 — controller of an object (the enchanted permanent's current controller)
• CR 503.1 — the upkeep step

Verification

• cargo fmt --all — clean
• scripts/check-parser-combinators.sh — clean
• New parser unit tests in parser::oracle::tests:
  • super_intelligence_upkeep_scoped_to_enchanted_creature_controller — asserts phase == Upkeep, valid_target == ParentTargetController, and the card fully parses (no Unimplemented).
  • each_player_upkeep_phase_trigger_stays_unscoped — regression: a genuine "each player's upkeep" Howling-Mine trigger keeps valid_target == None (fires every turn).
• Full parser::oracle::tests suite green.

Scope note

The "enchanted player's <phase>" player-enchant path (AttachedTo) is unchanged; the new arm is else if, so player-enchant Auras are unaffected. The existing Aggression card ("the end step of enchanted creature's controller") now also gains correct turn-owner scoping as a member of the same class.

[gemini-code-assist]

Code Review

This pull request implements scoping for Aura phase triggers to the controller of the enchanted permanent or creature (e.g., "enchanted creature's controller") by introducing TargetFilter::ParentTargetController and parsing the corresponding Oracle phrases. However, the parser implementation in oracle_trigger.rs uses fragile substring checks (scan_contains) instead of idiomatic nom combinators, which violates the repository's strict architectural rule (R1) requiring combinators for parsing dispatch.

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[gemini-code-assist]

Avoid using fragile substring checks like scan_contains for parsing Oracle phrases, as this bypasses the robust nom-based parser and creates fragile matches. Instead, decompose compound phrases (such as "enchanted 's controller") into modular, reusable parsers for constituent parts and compose them using idiomatic combinator aggregates (like nested alt and tag sequences) to prevent combinatorial explosion and improve maintainability.

Suggested change

	else if scan_contains(phase_text, "enchanted creature's controller")
	|| scan_contains(phase_text, "enchanted creature\u{2019}s controller")
	|| scan_contains(phase_text, "enchanted permanent's controller")
	|| scan_contains(phase_text, "enchanted permanent\u{2019}s controller")
	let mut enchanted_controller = preceded(
	tag("enchanted "),
	terminated(card_type, alt((tag("'s controller"), tag("’s controller"))))
	);

References

1. Avoid verbatim string equality for parsing Oracle phrases as it bypasses the robust nom-based parser and creates fragile matches. Instead, decompose compound phrases into modular, reusable parsers for constituent parts and compose them using idiomatic combinator aggregates.

[matthewevans]

[MED] Parse the enchanted-permanent controller phrase with composed nom axes instead of literal phrase scans. Evidence: crates/engine/src/parser/oracle_trigger.rs:11590 adds four scan_contains checks for the creature/permanent and ASCII/curly-apostrophe variants. Why it matters: this is new Oracle parsing dispatch, and the project rule is to compose the grammar dimensions (enchanted + object kind + possessive controller) with nom combinators so future sibling forms do not require another cartesian list of literals. Suggested fix: add a small phase-trigger helper that parses enchanted {creature|permanent}{'s|’s} controller with tag/alt/preceded/terminated (or an existing possessive helper if one fits), then set ParentTargetController from that parsed result.

[github-actions]

Parse changes introduced by this PR · 27 card(s), 1 signature(s) (baseline: main 1c3d1e1a9dd3)

27 card(s) · trigger/Phase · field valid target: ∅ → parent target's controller

Examples: Aggression, Apathy, Dance of the Dead (+24 more)

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

[philluiz2323]

Thanks — addressed in f5e2c75. Replaced the four scan_contains literals with a single composed combinator parse_enchanted_controller_phrase that parses the grammar axes (tag("enchanted ") + alt((tag("creature"), tag("permanent"))) + alt((tag("'s"), tag("’s"))) + tag(" controller")), matched at any word boundary via scan_at_word_boundaries since the phrase trails the phase noun ("the upkeep of …"). A new object-kind sibling is now one alt() arm rather than another pair of literals. Behavior is unchanged; fmt and the parser-combinator gate pass and cargo check is clean.

[matthewevans]

Maintainer review: current head resolves the prior nom-combinator finding; parse diff is scoped to enchanted permanent controller phase triggers.