Resolve the subject class at the earliest delimiter

LeadingClass checked delimiters in a fixed order (":" first), so a tag or name
filter written before a pseudo-class — the conventional order, e.g.
"Part.Enemy:not(#Boss)" — cut at the ":" and widened the result to Instance[].
Cutting at every delimiter in turn keeps the prefix before the earliest one,
making the order irrelevant. The "[" check is dropped: filters are stripped
before LeadingClass runs.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01B24Kfw4PGCgm4NQDmUVEMN

Author: claude

include/selector.d.ts

@@ -76,20 +76,9 @@ declare namespace Selector {
 	// Only the final combinator segment can determine the subject type.
 	type LastSegment<S extends string> = S extends `${string}>${infer R}` ? LastSegment<R> : S;
 
-	type LeadingClass<S extends string> =
-		Trim<S> extends infer T extends string
-			? T extends `${infer C}:${string}`
-				? Trim<C>
-				: T extends `${infer C}.${string}`
-					? Trim<C>
-					: T extends `${infer C}#${string}`
-						? Trim<C>
-						: T extends `${infer C}[${string}`
-							? Trim<C>
-							: T extends `${infer C} ${string}`
-								? Trim<C>
-								: T
-			: never;
+	type CutAt<S extends string, D extends string> = S extends `${infer Prefix}${D}${string}` ? Prefix : S;
+
+	type LeadingClass<S extends string> = CutAt<CutAt<CutAt<CutAt<Trim<S>, ":">, ".">, "#">, " ">;
 
 	// Filters do not affect the subject class, but their values can contain selector separators.
 	type StripFiltersAndParens<S extends string> = S extends `${infer A}[${string}]${infer B}`

tests/selector.ts

@@ -49,6 +49,10 @@ const hasPseudo = game.QueryDescendants("Model:has(.Child)"); //=> Model[]
 const pseudoChild = game.QueryDescendants("Folder > Part:not(#Excluded)"); //=> Part[]
 const pseudoList = game.QueryDescendants("Part:not(.A), Model:has(#B)"); //=> (Part | Model)[]
 const pseudoInnerComma = game.QueryDescendants("Part:not(.A, .B, .C)"); //=> Part[]
+const tagThenPseudo = game.QueryDescendants("Part.Enemy:not(#Boss)"); //=> Part[]
+const nameThenPseudo = game.QueryDescendants("Part#Boss:has(.Weapon)"); //=> Part[]
+const tagThenPseudoList = game.QueryDescendants("Part.Enemy:not(.A), Model"); //=> (Part | Model)[]
+const pseudoThenTag = game.QueryDescendants("Part:not(.Rotten).Fruit"); //=> Part[]
 const pseudoQuotedInnerComma = game.QueryDescendants("Part:has(Model[Name = 'a,b'], Folder)"); //=> Part[]
 const pseudoNestedList = game.QueryDescendants("Part:has(Model:has([Name = 'a,b']), Folder), TextButton"); //=> (Part | TextButton)[]
 const pseudoTrailingCombinator = game.QueryDescendants("Part:has(Model:has(.x)) >"); //=> Instance[]