From 372159011839d38aac18fd27695324f6deaf761d Mon Sep 17 00:00:00 2001
From: Ivan Tham <pickfire@riseup.net>
Date: Mon, 31 May 2021 23:36:39 +0800
Subject: [PATCH] Add full debug layout for type layout doc

See what you can see for `#[rustc_layout(debug)]` but with rustdoc which
is very useful, rather than writing some stuff you can just browse through
the docs. I think it may be useful to put it in json and have something
process it and do sort of `ncdu` to easily optimize on type sizes.
---
 src/librustdoc/html/render/print_item.rs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index e06168c708c18..d95633302ac49 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -1570,6 +1570,14 @@ fn document_type_layout(w: &mut Buffer, cx: &Context<'_>, ty_def_id: DefId) {
                     pl = if bytes == 1 { "" } else { "s" },
                 );
             }
+            writeln!(
+                w,
+                "<details class=\"rustdoc-toggle\">\
+                    <summary>Full debug layout</summary>\
+                    <pre><code>{:#?}</code></pre>\
+                </details>",
+                ty_layout.layout,
+            );
         }
         // This kind of layout error can occur with valid code, e.g. if you try to
         // get the layout of a generic type such as `Vec<T>`.