From 874300e1ba9ff36b496eb8053b16d8af36050fbe Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Mon, 26 Oct 2026 12:16:54 -0700
Subject: [PATCH] Only pre-size the printer buffer when printing a whole file

Write grew the writer by the full source file length for every call,
including when printing a single type node for typeToString or the
type baselines. Each resulting string then pinned a buffer the size
of the file; for largeControlFlowGraph.ts the types baseline retained
over 3GB this way, which exhausts the 4GB wasm address space.
---
 tsc/internal/printer/printer.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tsc/internal/printer/printer.go b/tsc/internal/printer/printer.go
index a27452d51472d..46bb47c25ebad 100644
--- a/tsc/internal/printer/printer.go
+++ b/tsc/internal/printer/printer.go
@@ -5095,7 +5095,7 @@ func (p *Printer) Write(node *ast.Node, sourceFile *ast.SourceFile, writer EmitT
 	}
 	p.writer = writer
 	p.writer.Clear()
-	if sourceFile != nil {
+	if sourceFile != nil && node == sourceFile.AsNode() {
 		if grower, ok := p.writer.(interface{ Grow(n int) }); ok {
 			grower.Grow(len(sourceFile.Text()))
 		}