fix(body): handle CASE depth in body statement formatting

pkg/format/body.go

@@ -379,6 +379,7 @@ func formatBodyStatements(text string, st config.Style) string {
 		stmt          []bline
 		parenDepth    int
 		blockDepth    int // 0=col-0 (BEGIN/END/EXCEPTION), 1=body, 2=nested…
+		caseDepth     int // depth of open CASE…END expressions (WHEN…THEN is not a block opener)
 		inException   bool
 		pendingBlanks int
 		depthInc      bool // increment blockDepth after next flush
@@ -529,18 +530,41 @@ func formatBodyStatements(text string, st config.Style) string {
 			}
 			if parenDepth == 0 && tok.Kind == lexer.Ident {
 				lastD0Kw = lowerASCII(tok.Text)
+				switch lastD0Kw {
+				case "case":
+					caseDepth++
+				case "end":
+					if caseDepth > 0 {
+						caseDepth--
+					}
+				}
 			}
 		}
 
 		if parenDepth == 0 && len(stmt) > 0 {
 			switch lastD0Kw {
-			case "then", "loop", "begin":
+			case "then":
+				// A THEN ending a CASE…WHEN branch is not a PL/pgSQL block
+				// opener; only one matching END closes the whole CASE, so
+				// treating each WHEN…THEN as a block open would permanently
+				// inflate blockDepth.
+				if caseDepth == 0 {
+					fw0 := lowerASCII(firstBodyKeyword(stmt[0].text))
+					if fw0 != "elsif" && fw0 != "elseif" {
+						depthInc = true
+					}
+					flush()
+				}
+			case "loop", "begin":
 				fw0 := lowerASCII(firstBodyKeyword(stmt[0].text))
 				if fw0 != "elsif" && fw0 != "elseif" {
 					depthInc = true
 				}
 				flush()
 			case "else", "exception":
+				if caseDepth > 0 {
+					break
+				}
 				flush()
 			}
 		}