Fix window function parsing for named window references with clauses

- Fix OVER (name clauses...) to not return early after parsing the name
- Add named window reference handling in WINDOW clause definitions
  (e.g., w1 AS (w0 ORDER BY ...))

Fixes 01591_window_functions (4 statements) and 02378_analyzer_projection_names.

Author: claude

parser/expression.go

@@ -749,16 +749,16 @@ func (p *Parser) parseWindowSpec() *ast.WindowSpec {
 		return spec
 	}
 
-	// Check for named window reference inside parentheses: OVER (w0)
+	// Check for named window reference inside parentheses: OVER (w0) or OVER (w0 ORDER BY ...)
 	// This happens when the identifier is not a known clause keyword
 	if p.currentIs(token.IDENT) {
 		upper := strings.ToUpper(p.current.Value)
 		// If it's not a window clause keyword, it's a named window reference
 		if upper != "PARTITION" && upper != "ORDER" && upper != "ROWS" && upper != "RANGE" && upper != "GROUPS" {
 			spec.Name = p.current.Value
 			p.nextToken()
-			p.expect(token.RPAREN)
-			return spec
+			// Don't return early - there may be more clauses after the window name
+			// e.g., OVER (w1 ROWS UNBOUNDED PRECEDING)
 		}
 	}
 

parser/parser.go

@@ -6720,6 +6720,15 @@ func (p *Parser) parseWindowDefinitions() []*ast.WindowDefinition {
 			Position: p.current.Pos,
 		}
 
+		// Check for named window reference (e.g., w1 as (w0 ORDER BY ...))
+		if p.currentIs(token.IDENT) {
+			upper := strings.ToUpper(p.current.Value)
+			if upper != "PARTITION" && upper != "ORDER" && upper != "ROWS" && upper != "RANGE" && upper != "GROUPS" {
+				spec.Name = p.current.Value
+				p.nextToken()
+			}
+		}
+
 		// Parse PARTITION BY
 		if p.currentIs(token.PARTITION) {
 			p.nextToken()

parser/testdata/01591_window_functions/metadata.json

@@ -1,8 +1,2 @@
 {
-  "explain_todo": {
-    "stmt107": true,
-    "stmt108": true,
-    "stmt109": true,
-    "stmt110": true
-  }
 }

parser/testdata/02378_analyzer_projection_names/metadata.json

@@ -1,6 +1,5 @@
 {
   "explain_todo": {
-    "stmt185": true,
     "stmt67": true
   }
 }