From 6a8a422b9d36bb180e9b56654cb270bfc574f64c Mon Sep 17 00:00:00 2001
From: Bryce Kwon <bryce@brycekwon.com>
Date: Sat, 31 Oct 2026 13:14:35 -0700
Subject: Render markdown and man pages through one function

Everything that can raise already runs inside the parse and emit
pcalls, so the outer one in filter_close could only ever have sent the
page a second time. The size check moves to the dispatch with it.
---
 custom/extensions/about-render.lua | 46 +++++++++++++++-----------------------
 1 file changed, 18 insertions(+), 28 deletions(-)

(limited to 'custom')

diff --git a/custom/extensions/about-render.lua b/custom/extensions/about-render.lua
index f330d04..3ae57e7 100644
--- a/custom/extensions/about-render.lua
+++ b/custom/extensions/about-render.lua
@@ -339,6 +339,18 @@ end
 -- Both parse into a node tree before anything is emitted, so a failed parse
 -- falls back to plain text without leaving half a page behind.
 
+local function render_blocks(text, parse)
+	local ok, blocks = pcall(parse, text)
+	if not ok then
+		return render_plaintext(text)
+	end
+	html("<div class='markdown'>")
+	-- Emitting is wrapped so a bug there can at worst truncate the page,
+	-- never end the request in an error.
+	pcall(emit_blocks, blocks)
+	html("</div>")
+end
+
 local render_markdown, render_man
 
 if has_lpeg then
@@ -680,19 +692,9 @@ if has_lpeg then
 	end
 
 	render_markdown = function(text)
-		if #text > max_bytes then
-			return render_plaintext(text)
-		end
-		local ok, blocks = pcall(parse_blocks, split_lines(text), 0)
-		if not ok then
-			return render_plaintext(text)
-		end
-		html("<div class='markdown'>")
-		-- Emitting is wrapped so a bug there can at worst
-		-- truncate the page, never raise and let the outer
-		-- fallback duplicate what has already been sent.
-		pcall(emit_blocks, blocks)
-		html("</div>")
+		render_blocks(text, function(t)
+			return parse_blocks(split_lines(t), 0)
+		end)
 	end
 
 	-- Roff fonts are a current state carried across a run rather than
@@ -987,16 +989,7 @@ if has_lpeg then
 	end
 
 	render_man = function(text)
-		if #text > max_bytes then
-			return render_plaintext(text)
-		end
-		local ok, blocks = pcall(parse_man, text)
-		if not ok then
-			return render_plaintext(text)
-		end
-		html("<div class='markdown'>")
-		pcall(emit_blocks, blocks)
-		html("</div>")
+		render_blocks(text, parse_man)
 	end
 else
 	-- No lpeg, so markdown and man readmes read as escaped source, not
@@ -1052,10 +1045,7 @@ function filter_close()
 	local text = replace_nul(table.concat(chunks))
 	chunks = {}
 	local ext = (filename:match("%.([^.]+)$") or ""):lower()
-	local render = handlers[ext] or render_plaintext
-	local ok = pcall(render, text)
-	if not ok then
-		render_plaintext(text)
-	end
+	local render = #text <= max_bytes and handlers[ext] or render_plaintext
+	render(text)
 	return 0
 end
-- 
cgit