fix(parser): cluster 41

crates/engine/src/parser/oracle_classifier.rs

@@ -1,8 +1,8 @@
 use crate::parser::oracle_nom::error::OracleError;
 use nom::branch::alt;
 use nom::bytes::complete::tag;
-use nom::combinator::verify;
-use nom::sequence::terminated;
+use nom::combinator::{opt, verify};
+use nom::sequence::{preceded, terminated};
 use nom::Parser;
 
 use super::oracle_nom::primitives as nom_primitives;
@@ -464,10 +464,21 @@ fn is_static_compound_pattern(lower: &str) -> bool {
     {
         return false;
     }
-    if alt((
-        tag::<_, _, OracleError<'_>>("you may play"),
-        tag("you may cast"),
-    ))
+    // CR 604.2 + CR 601.2a: head-anchor the "you may play"/"you may cast"
+    // permission lead, allowing an optional leading once-per-turn frequency
+    // phrase ("Once during each of your turns, " / "Once each turn, ") to be
+    // stripped first. This classifies the disjunctive once-per-turn play/cast-
+    // from-zone permission (The Eighth Doctor, Serra Paragon) as static so it
+    // routes ahead of the Priority 8 "would" replacement fallback — the granted
+    // rider's "would leave the battlefield" text would otherwise misclassify the
+    // whole line as a replacement. Class-level anchor, not a per-card branch.
+    if preceded(
+        opt(alt((
+            tag::<_, _, OracleError<'_>>("once during each of your turns, "),
+            tag("once each turn, "),
+        ))),
+        alt((tag("you may play"), tag("you may cast"))),
+    )
     .parse(lower)
     .is_ok()
         && (scan_contains(lower, "from your graveyard")

crates/engine/src/parser/oracle_static/restriction.rs

@@ -1448,6 +1448,26 @@ pub(crate) fn try_parse_graveyard_cast_permission(
         );
     }
 
+    // CR 305.1 + CR 601.2a + CR 700.6: Disjunctive once-per-turn permission —
+    // "Once during each of your turns, you may play a <land-filter> or cast a
+    // <spell-filter> from your graveyard." (The Eighth Doctor, Serra Paragon).
+    // `Play` mode covers both the land-play branch (CR 305.1) and the
+    // spell-cast branch (CR 601.2a); the two branch filters are merged so the
+    // permission's `affected` admits either class of card. Parsed before the
+    // single-verb dispatch below because the disjunctive lead shares the
+    // "once during each of your turns, you may" prefix with the cast-only form.
+    //
+    // The granted leave-battlefield rider ("If you do, it gains \"…exile…\"")
+    // that may follow is a CR 614.1a Moved replacement on the *resolved*
+    // permanent (origin Battlefield → Exile), NOT the stack-exit
+    // `graveyard_destination_replacement` (which is structurally unreachable for
+    // permanent spells). Attaching it requires a resolution-grant carrier on the
+    // permission — deferred per the plan's STOP gate — so it is left `None` here
+    // and the trailing rider text is tolerated rather than modeled.
+    if let Some(def) = try_parse_disjunctive_graveyard_cast_permission(text, lower) {
+        return Some(def);
+    }
+
     // Determine pattern and extract the rest after the prefix
     let (rest, frequency, play_mode) = if let Some(r) = nom_tag_lower(
         lower,
@@ -1518,6 +1538,125 @@ pub(crate) fn try_parse_graveyard_cast_permission(
     Some(def)
 }
 
+/// CR 305.1 + CR 601.2a + CR 700.6: Parse the disjunctive once-per-turn
+/// graveyard play/cast permission — "Once during each of your turns, you may
+/// play a <land-filter> or cast a <spell-filter> from your graveyard." — into a
+/// single `GraveyardCastPermission { frequency: OncePerTurn, play_mode: Play }`
+/// whose `affected` filter is the union of the two branch filters.
+///
+/// Two zone-placement variants are accepted (both observed in printed cards):
+/// - tail-zone: "play a <land> or cast a <spell> from your graveyard"
+///   (The Eighth Doctor — "from your graveyard" once, at the end).
+/// - per-branch-zone: "play a <land> from your graveyard or cast a <spell> from
+///   your graveyard" (Serra Paragon — "from your graveyard" on each branch).
+///
+/// The parser parses whatever filter each branch carries (it does NOT assume
+/// "historic"): Serra Paragon's spell branch carries "mana value 3 or less",
+/// proving the filter axis is general. When both branches resolve to the same
+/// filter (The Eighth Doctor: both "historic permanent"), the union collapses
+/// to that single filter; otherwise it emits `TargetFilter::Or`.
+///
+/// Any trailing rider ("If you do, it gains \"…\"") is tolerated and ignored —
+/// the granted leave-battlefield exile rider is a CR 614.1a Moved replacement on
+/// the resolved permanent that requires resolution-grant plumbing (deferred).
+fn try_parse_disjunctive_graveyard_cast_permission(
+    text: &str,
+    lower: &str,
+) -> Option<StaticDefinition> {
+    // CR 601.2a: Frequency prefix. Only the once-per-turn lead is a real printed
+    // shape for this disjunctive form today; accept both the canonical wording
+    // and the shorter "once each turn" synonym via the file-wide `or_else` chain.
+    let rest = nom_tag_lower(
+        lower,
+        lower,
+        "once during each of your turns, you may play ",
+    )
+    .or_else(|| nom_tag_lower(lower, lower, "once each turn, you may play "))?;
+
+    // CR 305.1 + CR 601.2a: The disjunction connector " or cast " splits the
+    // land-play branch from the spell-cast branch. `split_once_on` is the
+    // structural "everything up to delimiter" combinator.
+    let (land_branch, spell_branch) = nom_primitives::split_once_on(rest, " or cast ")
+        .ok()
+        .map(|(_, pair)| pair)?;
+
+    // The spell branch must end with the source-zone anchor. Strip a per-branch
+    // " from your graveyard" if present (Serra form); otherwise the tail-zone
+    // anchor (Eighth form) lives on the spell branch alone.
+    let spell_branch = strip_graveyard_zone_anchor(spell_branch)?;
+
+    // The land branch optionally carries its own zone anchor (Serra form); strip
+    // it when present so the bare filter phrase reaches the filter parser.
+    let land_branch = strip_graveyard_zone_anchor(land_branch).unwrap_or(land_branch);
+
+    let land_filter = parse_graveyard_branch_filter(land_branch)?;
+    let spell_filter = parse_graveyard_branch_filter(spell_branch)?;
+
+    // CR 700.6: a land is itself a permanent, so when both branches resolve to
+    // the same typed filter (historic land ⊆ historic permanent), collapse the
+    // union to that single filter rather than emitting a redundant `Or`.
+    let affected = if land_filter == spell_filter {
+        land_filter
+    } else {
+        TargetFilter::Or {
+            filters: vec![land_filter, spell_filter],
+        }
+    };
+
+    Some(
+        StaticDefinition::new(StaticMode::GraveyardCastPermission {
+            frequency: CastFrequency::OncePerTurn,
+            // CR 305.1: `Play` covers both the land-play and spell-cast branches.
+            play_mode: CardPlayMode::Play,
+            // Stack-exit redirect is wrong for the granted leave-battlefield
+            // rider (see doc comment); leave it unset.
+            graveyard_destination_replacement: None,
+        })
+        .affected(affected)
+        .description(text.to_string()),
+    )
+}
+
+/// Strip the trailing " from your graveyard" source-zone anchor (plus any
+/// leading whitespace) from a branch phrase, returning the bare filter text.
+/// Returns `None` when the anchor is absent.
+fn strip_graveyard_zone_anchor(branch: &str) -> Option<&str> {
+    nom_primitives::split_once_on(branch, " from your graveyard")
+        .ok()
+        .map(|(_, (before, _))| before.trim())
+}
+
+/// Strip the leading article and trailing " spell"/" spells" from a single
+/// disjunctive-permission branch, then resolve it through
+/// `parse_graveyard_permission_filter`. Mirrors the cleanup the single-verb
+/// graveyard parser performs, so both paths share one filter grammar. Returns
+/// `None` if the branch does not resolve to a usable typed filter.
+fn parse_graveyard_branch_filter(branch: &str) -> Option<TargetFilter> {
+    let branch = branch.trim();
+    // Strip the leading article ("a "/"an ").
+    let branch = nom_tag_lower(branch, branch, "a ")
+        .or_else(|| nom_tag_lower(branch, branch, "an "))
+        .unwrap_or(branch);
+
+    // Drop " spell"/" spells" so `parse_type_phrase` sees the bare type word;
+    // "land"/"lands" is already a valid type phrase and needs no stripping.
+    let cleaned: Cow<str> = if nom_primitives::scan_contains(branch, "spells") {
+        Cow::Owned(branch.replacen(" spells", "", 1))
+    } else if nom_primitives::scan_contains(branch, "spell") {
+        Cow::Owned(branch.replacen(" spell", "", 1))
+    } else {
+        Cow::Borrowed(branch)
+    };
+
+    let (filter, _self_ref) = parse_graveyard_permission_filter(&cleaned);
+    // Reject the unparseable fallbacks so a branch we cannot model declines the
+    // whole disjunctive parse rather than silently admitting everything.
+    match &filter {
+        TargetFilter::Typed(tf) if !tf.type_filters.is_empty() => Some(filter),
+        _ => None,
+    }
+}
+
 /// CR 122.2 + CR 113.6b: Parse the counter-persistence static — "Counters
 /// remain on ~ as it moves to any zone other than [zone list]." Overrides the
 /// default CR 122.2 rule that counters cease to exist on a zone change, except

crates/engine/src/parser/oracle_static/tests.rs

@@ -7540,6 +7540,144 @@ fn graveyard_cast_permission_muldrotha_legacy_and() {
     ));
 }
 
+/// CR 305.1 + CR 601.2a + CR 700.6: The Eighth Doctor's disjunctive permission
+/// — "Once during each of your turns, you may play a historic land or cast a
+/// historic permanent spell from your graveyard." — lowers to a single
+/// `GraveyardCastPermission { frequency: OncePerTurn, play_mode: Play,
+/// graveyard_destination_replacement: None }`. The two branches resolve to
+/// distinct typed filters (historic land vs. historic permanent), so the merged
+/// `affected` is a `TargetFilter::Or` over both — each branch carries the
+/// `Historic` property (CR 700.6). The trailing granted leave-battlefield rider
+/// is tolerated and does not block the permission.
+#[test]
+fn graveyard_cast_permission_disjunctive_eighth_doctor_tail_zone() {
+    let text = "Once during each of your turns, you may play a historic land or cast a historic permanent spell from your graveyard. If you do, it gains \"If ~ would leave the battlefield, exile it instead of putting it anywhere else.\"";
+    let def = parse_static_line(text).expect("should parse The Eighth Doctor disjunctive line");
+    assert!(
+        matches!(
+            def.mode,
+            StaticMode::GraveyardCastPermission {
+                frequency: CastFrequency::OncePerTurn,
+                play_mode: CardPlayMode::Play,
+                graveyard_destination_replacement: None,
+            }
+        ),
+        "expected OncePerTurn + Play + no stack-exit redirect, got {:?}",
+        def.mode
+    );
+    let filter = def.affected.expect("should have affected filter");
+    let TargetFilter::Or { filters } = filter else {
+        panic!("expected Or over the historic land / historic permanent branches, got {filter:?}");
+    };
+    assert_eq!(
+        filters.len(),
+        2,
+        "expected two branch filters, got {filters:?}"
+    );
+    // Land branch: historic land.
+    assert!(
+        matches!(
+            &filters[0],
+            TargetFilter::Typed(tf)
+                if tf.type_filters.contains(&TypeFilter::Land)
+                    && tf.properties.contains(&FilterProp::Historic)
+        ),
+        "expected first branch to be a historic Land filter, got {:?}",
+        filters[0]
+    );
+    // Spell branch: historic permanent.
+    assert!(
+        matches!(
+            &filters[1],
+            TargetFilter::Typed(tf)
+                if tf.type_filters.contains(&TypeFilter::Permanent)
+                    && tf.properties.contains(&FilterProp::Historic)
+        ),
+        "expected second branch to be a historic Permanent filter, got {:?}",
+        filters[1]
+    );
+}
+
+/// CR 305.1 + CR 601.2a: Serra Paragon's per-branch-zone form — "play a land
+/// from your graveyard or cast a permanent spell with mana value 3 or less from
+/// your graveyard" — proves the disjunctive parser's filter axis is general: the
+/// two branches differ (bare land vs. permanent with a mana-value bound), so the
+/// merged `affected` is a `TargetFilter::Or` over both branch filters, NOT a
+/// hard-coded "historic" assumption. This tests the building block (any two
+/// graveyard branch filters), not the Doctor string.
+#[test]
+fn graveyard_cast_permission_disjunctive_serra_paragon_per_branch_zone() {
+    let text = "Once during each of your turns, you may play a land from your graveyard or cast a permanent spell with mana value 3 or less from your graveyard.";
+    let def = parse_static_line(text).expect("should parse Serra Paragon disjunctive line");
+    assert!(
+        matches!(
+            def.mode,
+            StaticMode::GraveyardCastPermission {
+                frequency: CastFrequency::OncePerTurn,
+                play_mode: CardPlayMode::Play,
+                graveyard_destination_replacement: None,
+            }
+        ),
+        "expected OncePerTurn + Play, got {:?}",
+        def.mode
+    );
+    let filter = def.affected.expect("should have affected filter");
+    let TargetFilter::Or { filters } = filter else {
+        panic!("expected divergent branches to produce Or, got {filter:?}");
+    };
+    assert_eq!(
+        filters.len(),
+        2,
+        "expected two branch filters, got {filters:?}"
+    );
+    // Land branch: bare Land filter (no properties).
+    assert!(
+        matches!(
+            &filters[0],
+            TargetFilter::Typed(tf)
+                if tf.type_filters.contains(&TypeFilter::Land) && tf.properties.is_empty()
+        ),
+        "expected first branch to be a bare Land filter, got {:?}",
+        filters[0]
+    );
+    // Spell branch: Permanent with a mana-value (Cmc) bound.
+    let TargetFilter::Typed(spell_tf) = &filters[1] else {
+        panic!("expected second branch Typed, got {:?}", filters[1]);
+    };
+    assert!(
+        spell_tf.type_filters.contains(&TypeFilter::Permanent),
+        "expected Permanent type filter on spell branch, got {:?}",
+        spell_tf.type_filters
+    );
+    assert!(
+        spell_tf.properties.iter().any(|p| matches!(
+            p,
+            FilterProp::Cmc {
+                comparator: Comparator::LE,
+                ..
+            }
+        )),
+        "expected CmcLE bound on spell branch, got {:?}",
+        spell_tf.properties
+    );
+}
+
+/// CR 604.2 + CR 614.1a: the disjunctive once-per-turn permission line carries
+/// the granted rider's "would leave the battlefield" text, which would otherwise
+/// classify the whole line as a replacement (`would ` is the first replacement
+/// contains-pattern). The frequency-prefixed permission anchor must make
+/// `is_static_pattern` win so the line routes to static dispatch (Priority 7)
+/// ahead of the Priority 8 replacement gate. Guards the dispatch ordering for
+/// the whole once-per-turn play/cast-from-zone permission class.
+#[test]
+fn disjunctive_graveyard_permission_classifies_static_not_replacement() {
+    let lower = "once during each of your turns, you may play a historic land or cast a historic permanent spell from your graveyard. if you do, it gains \"if ~ would leave the battlefield, exile it instead of putting it anywhere else.\"";
+    assert!(
+        crate::parser::oracle_classifier::is_static_pattern(lower),
+        "disjunctive once-per-turn permission must classify as static"
+    );
+}
+
 // --- Alt-cost rider tests (Ninja Teen et al., CR 118.9 / CR 702.190a) ---
 
 #[test]