From a8a40ea9a4947a7b46421564517ee2aa4e3711f0 Mon Sep 17 00:00:00 2001
From: Mukund Lakshman <yaymukund@gmail.com>
Date: Fri, 1 Oct 2021 06:17:15 -0400
Subject: librustdoc: Use correct heading levels.

- Avoid multiple <h1>s on a page.
- The <h#> tags should follow a semantic hierarchy.
- Cap at h6 (no h7)
---
 src/tools/error_index_generator/main.rs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'src/tools/error_index_generator')

diff --git a/src/tools/error_index_generator/main.rs b/src/tools/error_index_generator/main.rs
index 01a3fc812b2..1ba283b1781 100644
--- a/src/tools/error_index_generator/main.rs
+++ b/src/tools/error_index_generator/main.rs
@@ -125,7 +125,8 @@ impl Formatter for HTMLFormatter {
                         &mut id_map,
                         ErrorCodes::Yes,
                         DEFAULT_EDITION,
-                        &Some(playground)
+                        &Some(playground),
+                        0
                     )
                     .into_string()
                 )?
-- 
cgit 1.4.1-3-g733a5


From 6518a0a8b9570b6d347a3c7b2c9b95e66cbbd013 Mon Sep 17 00:00:00 2001
From: Mukund Lakshman <yaymukund@gmail.com>
Date: Mon, 4 Oct 2021 21:08:58 -0400
Subject: Change `Markdown(...)` to `Markdown { ... }`

---
 src/librustdoc/externalfiles.rs         | 22 +++++++++++++++--
 src/librustdoc/html/markdown.rs         | 42 +++++++++++++++++++++++----------
 src/librustdoc/html/markdown/tests.rs   | 24 +++++++++++++++----
 src/librustdoc/html/render/mod.rs       | 38 ++++++++++++++---------------
 src/librustdoc/markdown.rs              | 11 ++++++++-
 src/tools/error_index_generator/main.rs | 18 +++++++-------
 6 files changed, 108 insertions(+), 47 deletions(-)

(limited to 'src/tools/error_index_generator')

diff --git a/src/librustdoc/externalfiles.rs b/src/librustdoc/externalfiles.rs
index 1fd5e2d5ef6..5cb654a606f 100644
--- a/src/librustdoc/externalfiles.rs
+++ b/src/librustdoc/externalfiles.rs
@@ -39,14 +39,32 @@ impl ExternalHtml {
         let bc = format!(
             "{}{}",
             bc,
-            Markdown(&m_bc, &[], id_map, codes, edition, playground, 0).into_string()
+            Markdown {
+                content: &m_bc,
+                links: &[],
+                ids: id_map,
+                error_codes: codes,
+                edition,
+                playground,
+                heading_level: 0
+            }
+            .into_string()
         );
         let ac = load_external_files(after_content, diag)?;
         let m_ac = load_external_files(md_after_content, diag)?;
         let ac = format!(
             "{}{}",
             ac,
-            Markdown(&m_ac, &[], id_map, codes, edition, playground, 0).into_string()
+            Markdown {
+                content: &m_ac,
+                links: &[],
+                ids: id_map,
+                error_codes: codes,
+                edition,
+                playground,
+                heading_level: 0
+            }
+            .into_string()
         );
         Some(ExternalHtml { in_header: ih, before_content: bc, after_content: ac })
     }
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index 56b580a0518..da1482f4e69 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -12,7 +12,15 @@
 //!
 //! let s = "My *markdown* _text_";
 //! let mut id_map = IdMap::new();
-//! let md = Markdown(s, &[], &mut id_map, ErrorCodes::Yes, Edition::Edition2015, &None, 0);
+//! let md = Markdown {
+//!     content: s,
+//!     links: &[],
+//!     ids: &mut id_map,
+//!     error_codes: ErrorCodes::Yes,
+//!     edition: Edition::Edition2015,
+//!     playground: &None,
+//!     heading_level: 0
+//! };
 //! let html = md.into_string();
 //! // ... something using html
 //! ```
@@ -69,19 +77,21 @@ pub(crate) fn summary_opts() -> Options {
 
 /// When `to_string` is called, this struct will emit the HTML corresponding to
 /// the rendered version of the contained markdown string.
-pub struct Markdown<'a>(
-    pub &'a str,
+pub struct Markdown<'a> {
+    pub content: &'a str,
     /// A list of link replacements.
-    pub &'a [RenderedLink],
+    pub links: &'a [RenderedLink],
     /// The current list of used header IDs.
-    pub &'a mut IdMap,
+    pub ids: &'a mut IdMap,
     /// Whether to allow the use of explicit error codes in doctest lang strings.
-    pub ErrorCodes,
+    pub error_codes: ErrorCodes,
     /// Default edition to use when parsing doctests (to add a `fn main`).
-    pub Edition,
-    pub &'a Option<Playground>,
-    pub u32,
-);
+    pub edition: Edition,
+    pub playground: &'a Option<Playground>,
+    /// Offset at which we render headings.
+    /// E.g. if `heading_level: 1`, then `# something` renders an `<h2>` instead of `<h1>`
+    pub heading_level: u32,
+}
 /// A tuple struct like `Markdown` that renders the markdown with a table of contents.
 crate struct MarkdownWithToc<'a>(
     crate &'a str,
@@ -1010,7 +1020,15 @@ impl LangString {
 
 impl Markdown<'_> {
     pub fn into_string(self) -> String {
-        let Markdown(md, links, mut ids, codes, edition, playground, level) = self;
+        let Markdown {
+            content: md,
+            links,
+            mut ids,
+            error_codes: codes,
+            edition,
+            playground,
+            heading_level,
+        } = self;
 
         // This is actually common enough to special-case
         if md.is_empty() {
@@ -1031,7 +1049,7 @@ impl Markdown<'_> {
 
         let mut s = String::with_capacity(md.len() * 3 / 2);
 
-        let p = HeadingLinks::new(p, None, &mut ids, level);
+        let p = HeadingLinks::new(p, None, &mut ids, heading_level);
         let p = Footnotes::new(p);
         let p = LinkReplacer::new(p.map(|(ev, _)| ev), links);
         let p = TableWrapper::new(p);
diff --git a/src/librustdoc/html/markdown/tests.rs b/src/librustdoc/html/markdown/tests.rs
index c6af7e5847c..b2c18c24011 100644
--- a/src/librustdoc/html/markdown/tests.rs
+++ b/src/librustdoc/html/markdown/tests.rs
@@ -147,8 +147,16 @@ fn test_lang_string_tokenizer() {
 fn test_header() {
     fn t(input: &str, expect: &str) {
         let mut map = IdMap::new();
-        let output = Markdown(input, &[], &mut map, ErrorCodes::Yes, DEFAULT_EDITION, &None, 0)
-            .into_string();
+        let output = Markdown {
+            content: input,
+            links: &[],
+            ids: &mut map,
+            error_codes: ErrorCodes::Yes,
+            edition: DEFAULT_EDITION,
+            playground: &None,
+            heading_level: 0,
+        }
+        .into_string();
         assert_eq!(output, expect, "original: {}", input);
     }
 
@@ -181,8 +189,16 @@ fn test_header() {
 fn test_header_ids_multiple_blocks() {
     let mut map = IdMap::new();
     fn t(map: &mut IdMap, input: &str, expect: &str) {
-        let output =
-            Markdown(input, &[], map, ErrorCodes::Yes, DEFAULT_EDITION, &None, 0).into_string();
+        let output = Markdown {
+            content: input,
+            links: &[],
+            ids: map,
+            error_codes: ErrorCodes::Yes,
+            edition: DEFAULT_EDITION,
+            playground: &None,
+            heading_level: 0,
+        }
+        .into_string();
         assert_eq!(output, expect, "original: {}", input);
     }
 
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 532dce99c0d..164d7453368 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -498,21 +498,21 @@ fn render_markdown(
     cx: &Context<'_>,
     md_text: &str,
     links: Vec<RenderedLink>,
-    level: u32,
+    heading_level: u32,
 ) {
     let mut ids = cx.id_map.borrow_mut();
     write!(
         w,
         "<div class=\"docblock\">{}</div>",
-        Markdown(
-            md_text,
-            &links,
-            &mut ids,
-            cx.shared.codes,
-            cx.shared.edition(),
-            &cx.shared.playground,
-            level
-        )
+        Markdown {
+            content: md_text,
+            links: &links,
+            ids: &mut ids,
+            error_codes: cx.shared.codes,
+            edition: cx.shared.edition(),
+            playground: &cx.shared.playground,
+            heading_level,
+        }
         .into_string()
     )
 }
@@ -1596,15 +1596,15 @@ fn render_impl(
             write!(
                 w,
                 "<div class=\"docblock\">{}</div>",
-                Markdown(
-                    &*dox,
-                    &i.impl_item.links(cx),
-                    &mut ids,
-                    cx.shared.codes,
-                    cx.shared.edition(),
-                    &cx.shared.playground,
-                    0
-                )
+                Markdown {
+                    content: &*dox,
+                    links: &i.impl_item.links(cx),
+                    ids: &mut ids,
+                    error_codes: cx.shared.codes,
+                    edition: cx.shared.edition(),
+                    playground: &cx.shared.playground,
+                    heading_level: 0
+                }
                 .into_string()
             );
         }
diff --git a/src/librustdoc/markdown.rs b/src/librustdoc/markdown.rs
index 82e6231782c..962712f5b91 100644
--- a/src/librustdoc/markdown.rs
+++ b/src/librustdoc/markdown.rs
@@ -70,7 +70,16 @@ crate fn render<P: AsRef<Path>>(
     let text = if !options.markdown_no_toc {
         MarkdownWithToc(text, &mut ids, error_codes, edition, &playground).into_string()
     } else {
-        Markdown(text, &[], &mut ids, error_codes, edition, &playground, 0).into_string()
+        Markdown {
+            content: text,
+            links: &[],
+            ids: &mut ids,
+            error_codes,
+            edition,
+            playground: &playground,
+            heading_level: 0,
+        }
+        .into_string()
     };
 
     let err = write!(
diff --git a/src/tools/error_index_generator/main.rs b/src/tools/error_index_generator/main.rs
index 1ba283b1781..f3c5d65935f 100644
--- a/src/tools/error_index_generator/main.rs
+++ b/src/tools/error_index_generator/main.rs
@@ -119,15 +119,15 @@ impl Formatter for HTMLFormatter {
                 write!(
                     output,
                     "{}",
-                    Markdown(
-                        desc,
-                        &[],
-                        &mut id_map,
-                        ErrorCodes::Yes,
-                        DEFAULT_EDITION,
-                        &Some(playground),
-                        0
-                    )
+                    Markdown {
+                        content: desc,
+                        links: &[],
+                        ids: &mut id_map,
+                        error_codes: ErrorCodes::Yes,
+                        edition: DEFAULT_EDITION,
+                        playground: &Some(playground),
+                        heading_level: 0
+                    }
                     .into_string()
                 )?
             }
-- 
cgit 1.4.1-3-g733a5


From 13558ee0a06c544e68978766d0508b62ef3e22f7 Mon Sep 17 00:00:00 2001
From: Mukund Lakshman <yaymukund@gmail.com>
Date: Mon, 4 Oct 2021 21:28:26 -0400
Subject: No need to default offset since we always override it.

---
 src/librustdoc/externalfiles.rs          |  4 +--
 src/librustdoc/html/markdown.rs          |  4 +--
 src/librustdoc/html/markdown/tests.rs    |  4 +--
 src/librustdoc/html/render/mod.rs        | 12 +++-----
 src/librustdoc/html/render/print_item.rs | 50 ++++++++++++++++----------------
 src/tools/error_index_generator/main.rs  |  2 +-
 6 files changed, 36 insertions(+), 40 deletions(-)

(limited to 'src/tools/error_index_generator')

diff --git a/src/librustdoc/externalfiles.rs b/src/librustdoc/externalfiles.rs
index 5cb654a606f..cb5c9edcde5 100644
--- a/src/librustdoc/externalfiles.rs
+++ b/src/librustdoc/externalfiles.rs
@@ -46,7 +46,7 @@ impl ExternalHtml {
                 error_codes: codes,
                 edition,
                 playground,
-                heading_level: 0
+                heading_level: 1
             }
             .into_string()
         );
@@ -62,7 +62,7 @@ impl ExternalHtml {
                 error_codes: codes,
                 edition,
                 playground,
-                heading_level: 0
+                heading_level: 1
             }
             .into_string()
         );
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index da1482f4e69..ef2f2f90301 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -19,7 +19,7 @@
 //!     error_codes: ErrorCodes::Yes,
 //!     edition: Edition::Edition2015,
 //!     playground: &None,
-//!     heading_level: 0
+//!     heading_level: 1
 //! };
 //! let html = md.into_string();
 //! // ... something using html
@@ -544,7 +544,7 @@ impl<'a, 'b, 'ids, I: Iterator<Item = SpannedEvent<'a>>> Iterator
                 self.buf.push_front((Event::Html(format!("{} ", sec).into()), 0..0));
             }
 
-            let level = std::cmp::min(level + self.level + 1, MAX_HEADER_LEVEL);
+            let level = std::cmp::min(level + self.level, MAX_HEADER_LEVEL);
             self.buf.push_back((Event::Html(format!("</a></h{}>", level).into()), 0..0));
 
             let start_tags = format!(
diff --git a/src/librustdoc/html/markdown/tests.rs b/src/librustdoc/html/markdown/tests.rs
index b2c18c24011..ee6a1997896 100644
--- a/src/librustdoc/html/markdown/tests.rs
+++ b/src/librustdoc/html/markdown/tests.rs
@@ -154,7 +154,7 @@ fn test_header() {
             error_codes: ErrorCodes::Yes,
             edition: DEFAULT_EDITION,
             playground: &None,
-            heading_level: 0,
+            heading_level: 1,
         }
         .into_string();
         assert_eq!(output, expect, "original: {}", input);
@@ -196,7 +196,7 @@ fn test_header_ids_multiple_blocks() {
             error_codes: ErrorCodes::Yes,
             edition: DEFAULT_EDITION,
             playground: &None,
-            heading_level: 0,
+            heading_level: 1,
         }
         .into_string();
         assert_eq!(output, expect, "original: {}", input);
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 164d7453368..8cf11e526fe 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -470,11 +470,7 @@ fn settings(root_path: &str, suffix: &str, themes: &[StylePath]) -> Result<Strin
     ))
 }
 
-fn document(w: &mut Buffer, cx: &Context<'_>, item: &clean::Item, parent: Option<&clean::Item>) {
-    document_at_level(w, cx, item, parent, 0)
-}
-
-fn document_at_level(
+fn document(
     w: &mut Buffer,
     cx: &Context<'_>,
     item: &clean::Item,
@@ -1344,7 +1340,7 @@ fn render_impl(
                         // because impls can't have a stability.
                         if item.doc_value().is_some() {
                             document_item_info(&mut info_buffer, cx, it, Some(parent));
-                            document_full(&mut doc_buffer, item, cx, 3);
+                            document_full(&mut doc_buffer, item, cx, 4);
                             short_documented = false;
                         } else {
                             // In case the item isn't documented,
@@ -1362,7 +1358,7 @@ fn render_impl(
                 } else {
                     document_item_info(&mut info_buffer, cx, item, Some(parent));
                     if rendering_params.show_def_docs {
-                        document_full(&mut doc_buffer, item, cx, 3);
+                        document_full(&mut doc_buffer, item, cx, 4);
                         short_documented = false;
                     }
                 }
@@ -1603,7 +1599,7 @@ fn render_impl(
                     error_codes: cx.shared.codes,
                     edition: cx.shared.edition(),
                     playground: &cx.shared.playground,
-                    heading_level: 0
+                    heading_level: 1
                 }
                 .into_string()
             );
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index 59a6925d8b4..f26ee84569b 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -16,10 +16,10 @@ use rustc_span::symbol::{kw, sym, Symbol};
 use rustc_target::abi::{Layout, Primitive, TagEncoding, Variants};
 
 use super::{
-    collect_paths_for_type, document, document_at_level, ensure_trailing_slash, item_ty_to_strs,
-    notable_traits_decl, render_assoc_item, render_assoc_items, render_attributes_in_code,
-    render_attributes_in_pre, render_impl, render_stability_since_raw, write_srclink,
-    AssocItemLink, Context, ImplRenderingParameters,
+    collect_paths_for_type, document, ensure_trailing_slash, item_ty_to_strs, notable_traits_decl,
+    render_assoc_item, render_assoc_items, render_attributes_in_code, render_attributes_in_pre,
+    render_impl, render_stability_since_raw, write_srclink, AssocItemLink, Context,
+    ImplRenderingParameters,
 };
 use crate::clean::{self, GetDefId};
 use crate::formats::item_type::ItemType;
@@ -173,7 +173,7 @@ fn toggle_close(w: &mut Buffer) {
 }
 
 fn item_module(w: &mut Buffer, cx: &Context<'_>, item: &clean::Item, items: &[clean::Item]) {
-    document(w, cx, item, None);
+    document(w, cx, item, None, 1);
 
     let mut indices = (0..items.len()).filter(|i| !items[*i].is_stripped()).collect::<Vec<usize>>();
 
@@ -485,7 +485,7 @@ fn item_function(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, f: &clean::
             notable_traits = notable_traits_decl(&f.decl, cx),
         );
     });
-    document(w, cx, it, None)
+    document(w, cx, it, None, 1)
 }
 
 fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Trait) {
@@ -608,7 +608,7 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
     });
 
     // Trait documentation
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     fn write_small_section_header(w: &mut Buffer, id: &str, title: &str, extra_content: &str) {
         write!(
@@ -626,7 +626,7 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
         let item_type = m.type_();
         let id = cx.derive_id(format!("{}.{}", item_type, name));
         let mut content = Buffer::empty_from(w);
-        document_at_level(&mut content, cx, m, Some(t), 3);
+        document(&mut content, cx, m, Some(t), 4);
         let toggled = !content.is_empty();
         if toggled {
             write!(w, "<details class=\"rustdoc-toggle\" open><summary>");
@@ -840,7 +840,7 @@ fn item_trait_alias(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clea
         );
     });
 
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     // Render any items associated directly to this alias, as otherwise they
     // won't be visible anywhere in the docs. It would be nice to also show
@@ -862,7 +862,7 @@ fn item_opaque_ty(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean:
         );
     });
 
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     // Render any items associated directly to this alias, as otherwise they
     // won't be visible anywhere in the docs. It would be nice to also show
@@ -893,7 +893,7 @@ fn item_typedef(
         );
     });
 
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     let def_id = it.def_id.expect_def_id();
     // Render any items associated directly to this alias, as otherwise they
@@ -911,7 +911,7 @@ fn item_union(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::Uni
         });
     });
 
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     let mut fields = s
         .fields
@@ -944,7 +944,7 @@ fn item_union(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::Uni
             if let Some(stability_class) = field.stability_class(cx.tcx()) {
                 write!(w, "<span class=\"stab {stab}\"></span>", stab = stability_class);
             }
-            document(w, cx, field, Some(it));
+            document(w, cx, field, Some(it), 1);
         }
     }
     let def_id = it.def_id.expect_def_id();
@@ -1026,7 +1026,7 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
         });
     });
 
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     if !e.variants.is_empty() {
         write!(
@@ -1055,7 +1055,7 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
             w.write_str("</code>");
             render_stability_since(w, variant, it, cx.tcx());
             w.write_str("</div>");
-            document(w, cx, variant, Some(it));
+            document(w, cx, variant, Some(it), 1);
             document_non_exhaustive(w, variant);
 
             use crate::clean::Variant;
@@ -1095,7 +1095,7 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
                                 f = field.name.as_ref().unwrap(),
                                 t = ty.print(cx)
                             );
-                            document(w, cx, field, Some(variant));
+                            document(w, cx, field, Some(variant), 1);
                         }
                         _ => unreachable!(),
                     }
@@ -1122,7 +1122,7 @@ fn item_macro(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Mac
             None,
         );
     });
-    document(w, cx, it, None)
+    document(w, cx, it, None, 1)
 }
 
 fn item_proc_macro(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, m: &clean::ProcMacro) {
@@ -1152,11 +1152,11 @@ fn item_proc_macro(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, m: &clean
             });
         }
     }
-    document(w, cx, it, None)
+    document(w, cx, it, None, 1)
 }
 
 fn item_primitive(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
     render_assoc_items(w, cx, it, it.def_id.expect_def_id(), AssocItemRender::All)
 }
 
@@ -1195,7 +1195,7 @@ fn item_constant(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, c: &clean::
         }
     });
 
-    document(w, cx, it, None)
+    document(w, cx, it, None, 1)
 }
 
 fn item_struct(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::Struct) {
@@ -1206,7 +1206,7 @@ fn item_struct(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::St
         });
     });
 
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     let mut fields = s
         .fields
@@ -1242,7 +1242,7 @@ fn item_struct(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::St
                     name = field_name,
                     ty = ty.print(cx)
                 );
-                document(w, cx, field, Some(it));
+                document(w, cx, field, Some(it), 1);
             }
         }
     }
@@ -1263,7 +1263,7 @@ fn item_static(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::St
             typ = s.type_.print(cx)
         );
     });
-    document(w, cx, it, None)
+    document(w, cx, it, None, 1)
 }
 
 fn item_foreign_type(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
@@ -1278,13 +1278,13 @@ fn item_foreign_type(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
         );
     });
 
-    document(w, cx, it, None);
+    document(w, cx, it, None, 1);
 
     render_assoc_items(w, cx, it, it.def_id.expect_def_id(), AssocItemRender::All)
 }
 
 fn item_keyword(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
-    document(w, cx, it, None)
+    document(w, cx, it, None, 1)
 }
 
 /// Compare two strings treating multi-digit numbers as single units (i.e. natural sort order).
diff --git a/src/tools/error_index_generator/main.rs b/src/tools/error_index_generator/main.rs
index f3c5d65935f..f89f28242a2 100644
--- a/src/tools/error_index_generator/main.rs
+++ b/src/tools/error_index_generator/main.rs
@@ -126,7 +126,7 @@ impl Formatter for HTMLFormatter {
                         error_codes: ErrorCodes::Yes,
                         edition: DEFAULT_EDITION,
                         playground: &Some(playground),
-                        heading_level: 0
+                        heading_level: 1
                     }
                     .into_string()
                 )?
-- 
cgit 1.4.1-3-g733a5


From f1425c7c3e62b519354d1a178181a66dad943b4e Mon Sep 17 00:00:00 2001
From: Mukund Lakshman <yaymukund@gmail.com>
Date: Mon, 4 Oct 2021 21:54:00 -0400
Subject: heading_level: u32 -> heading_offset: HeadingOffset

---
 src/librustdoc/externalfiles.rs          |  6 ++---
 src/librustdoc/html/markdown.rs          | 41 +++++++++++++++++++----------
 src/librustdoc/html/markdown/tests.rs    |  6 ++---
 src/librustdoc/html/render/mod.rs        | 42 ++++++++++++++++++------------
 src/librustdoc/html/render/print_item.rs | 44 ++++++++++++++++----------------
 src/librustdoc/markdown.rs               |  6 +++--
 src/tools/error_index_generator/main.rs  |  4 +--
 7 files changed, 88 insertions(+), 61 deletions(-)

(limited to 'src/tools/error_index_generator')

diff --git a/src/librustdoc/externalfiles.rs b/src/librustdoc/externalfiles.rs
index cb5c9edcde5..302fc5a6777 100644
--- a/src/librustdoc/externalfiles.rs
+++ b/src/librustdoc/externalfiles.rs
@@ -1,4 +1,4 @@
-use crate::html::markdown::{ErrorCodes, IdMap, Markdown, Playground};
+use crate::html::markdown::{ErrorCodes, HeadingOffset, IdMap, Markdown, Playground};
 use crate::rustc_span::edition::Edition;
 use std::fs;
 use std::path::Path;
@@ -46,7 +46,7 @@ impl ExternalHtml {
                 error_codes: codes,
                 edition,
                 playground,
-                heading_level: 1
+                heading_offset: HeadingOffset::H2,
             }
             .into_string()
         );
@@ -62,7 +62,7 @@ impl ExternalHtml {
                 error_codes: codes,
                 edition,
                 playground,
-                heading_level: 1
+                heading_offset: HeadingOffset::H2,
             }
             .into_string()
         );
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index ef2f2f90301..9f2e282fce1 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -8,7 +8,7 @@
 //! extern crate rustc_span;
 //!
 //! use rustc_span::edition::Edition;
-//! use rustdoc::html::markdown::{IdMap, Markdown, ErrorCodes};
+//! use rustdoc::html::markdown::{HeadingOffset, IdMap, Markdown, ErrorCodes};
 //!
 //! let s = "My *markdown* _text_";
 //! let mut id_map = IdMap::new();
@@ -19,7 +19,7 @@
 //!     error_codes: ErrorCodes::Yes,
 //!     edition: Edition::Edition2015,
 //!     playground: &None,
-//!     heading_level: 1
+//!     heading_offset: HeadingOffset::H2,
 //! };
 //! let html = md.into_string();
 //! // ... something using html
@@ -75,6 +75,16 @@ pub(crate) fn summary_opts() -> Options {
         | Options::ENABLE_SMART_PUNCTUATION
 }
 
+#[derive(Debug, Clone, Copy)]
+pub enum HeadingOffset {
+    H1 = 0,
+    H2,
+    H3,
+    H4,
+    H5,
+    H6,
+}
+
 /// When `to_string` is called, this struct will emit the HTML corresponding to
 /// the rendered version of the contained markdown string.
 pub struct Markdown<'a> {
@@ -89,8 +99,8 @@ pub struct Markdown<'a> {
     pub edition: Edition,
     pub playground: &'a Option<Playground>,
     /// Offset at which we render headings.
-    /// E.g. if `heading_level: 1`, then `# something` renders an `<h2>` instead of `<h1>`
-    pub heading_level: u32,
+    /// E.g. if `heading_offset: HeadingOffset::H2`, then `# something` renders an `<h2>`.
+    pub heading_offset: HeadingOffset,
 }
 /// A tuple struct like `Markdown` that renders the markdown with a table of contents.
 crate struct MarkdownWithToc<'a>(
@@ -502,12 +512,17 @@ struct HeadingLinks<'a, 'b, 'ids, I> {
     toc: Option<&'b mut TocBuilder>,
     buf: VecDeque<SpannedEvent<'a>>,
     id_map: &'ids mut IdMap,
-    level: u32,
+    heading_offset: HeadingOffset,
 }
 
 impl<'a, 'b, 'ids, I> HeadingLinks<'a, 'b, 'ids, I> {
-    fn new(iter: I, toc: Option<&'b mut TocBuilder>, ids: &'ids mut IdMap, level: u32) -> Self {
-        HeadingLinks { inner: iter, toc, buf: VecDeque::new(), id_map: ids, level }
+    fn new(
+        iter: I,
+        toc: Option<&'b mut TocBuilder>,
+        ids: &'ids mut IdMap,
+        heading_offset: HeadingOffset,
+    ) -> Self {
+        HeadingLinks { inner: iter, toc, buf: VecDeque::new(), id_map: ids, heading_offset }
     }
 }
 
@@ -544,7 +559,7 @@ impl<'a, 'b, 'ids, I: Iterator<Item = SpannedEvent<'a>>> Iterator
                 self.buf.push_front((Event::Html(format!("{} ", sec).into()), 0..0));
             }
 
-            let level = std::cmp::min(level + self.level, MAX_HEADER_LEVEL);
+            let level = std::cmp::min(level + (self.heading_offset as u32), MAX_HEADER_LEVEL);
             self.buf.push_back((Event::Html(format!("</a></h{}>", level).into()), 0..0));
 
             let start_tags = format!(
@@ -1027,7 +1042,7 @@ impl Markdown<'_> {
             error_codes: codes,
             edition,
             playground,
-            heading_level,
+            heading_offset,
         } = self;
 
         // This is actually common enough to special-case
@@ -1049,7 +1064,7 @@ impl Markdown<'_> {
 
         let mut s = String::with_capacity(md.len() * 3 / 2);
 
-        let p = HeadingLinks::new(p, None, &mut ids, heading_level);
+        let p = HeadingLinks::new(p, None, &mut ids, heading_offset);
         let p = Footnotes::new(p);
         let p = LinkReplacer::new(p.map(|(ev, _)| ev), links);
         let p = TableWrapper::new(p);
@@ -1071,7 +1086,7 @@ impl MarkdownWithToc<'_> {
         let mut toc = TocBuilder::new();
 
         {
-            let p = HeadingLinks::new(p, Some(&mut toc), &mut ids, 0);
+            let p = HeadingLinks::new(p, Some(&mut toc), &mut ids, HeadingOffset::H1);
             let p = Footnotes::new(p);
             let p = TableWrapper::new(p.map(|(ev, _)| ev));
             let p = CodeBlocks::new(p, codes, edition, playground);
@@ -1100,7 +1115,7 @@ impl MarkdownHtml<'_> {
 
         let mut s = String::with_capacity(md.len() * 3 / 2);
 
-        let p = HeadingLinks::new(p, None, &mut ids, 0);
+        let p = HeadingLinks::new(p, None, &mut ids, HeadingOffset::H1);
         let p = Footnotes::new(p);
         let p = TableWrapper::new(p.map(|(ev, _)| ev));
         let p = CodeBlocks::new(p, codes, edition, playground);
@@ -1318,7 +1333,7 @@ crate fn markdown_links(md: &str) -> Vec<MarkdownLink> {
     // There's no need to thread an IdMap through to here because
     // the IDs generated aren't going to be emitted anywhere.
     let mut ids = IdMap::new();
-    let iter = Footnotes::new(HeadingLinks::new(p, None, &mut ids, 0));
+    let iter = Footnotes::new(HeadingLinks::new(p, None, &mut ids, HeadingOffset::H1));
 
     for ev in iter {
         if let Event::Start(Tag::Link(kind, dest, _)) = ev.0 {
diff --git a/src/librustdoc/html/markdown/tests.rs b/src/librustdoc/html/markdown/tests.rs
index ee6a1997896..68ab002f138 100644
--- a/src/librustdoc/html/markdown/tests.rs
+++ b/src/librustdoc/html/markdown/tests.rs
@@ -1,5 +1,5 @@
 use super::{find_testable_code, plain_text_summary, short_markdown_summary};
-use super::{ErrorCodes, IdMap, Ignore, LangString, Markdown, MarkdownHtml};
+use super::{ErrorCodes, HeadingOffset, IdMap, Ignore, LangString, Markdown, MarkdownHtml};
 use rustc_span::edition::{Edition, DEFAULT_EDITION};
 
 #[test]
@@ -154,7 +154,7 @@ fn test_header() {
             error_codes: ErrorCodes::Yes,
             edition: DEFAULT_EDITION,
             playground: &None,
-            heading_level: 1,
+            heading_offset: HeadingOffset::H2,
         }
         .into_string();
         assert_eq!(output, expect, "original: {}", input);
@@ -196,7 +196,7 @@ fn test_header_ids_multiple_blocks() {
             error_codes: ErrorCodes::Yes,
             edition: DEFAULT_EDITION,
             playground: &None,
-            heading_level: 1,
+            heading_offset: HeadingOffset::H2,
         }
         .into_string();
         assert_eq!(output, expect, "original: {}", input);
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 8cf11e526fe..11682afdf89 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -67,7 +67,7 @@ use crate::html::format::{
     href, print_abi_with_space, print_constness_with_space, print_default_space,
     print_generic_bounds, print_where_clause, Buffer, HrefError, PrintWithSpace,
 };
-use crate::html::markdown::{Markdown, MarkdownHtml, MarkdownSummaryLine};
+use crate::html::markdown::{HeadingOffset, Markdown, MarkdownHtml, MarkdownSummaryLine};
 
 /// A pair of name and its optional document.
 crate type NameDoc = (String, Option<String>);
@@ -475,16 +475,16 @@ fn document(
     cx: &Context<'_>,
     item: &clean::Item,
     parent: Option<&clean::Item>,
-    level: u32,
+    heading_offset: HeadingOffset,
 ) {
     if let Some(ref name) = item.name {
         info!("Documenting {}", name);
     }
     document_item_info(w, cx, item, parent);
     if parent.is_none() {
-        document_full_collapsible(w, item, cx, level);
+        document_full_collapsible(w, item, cx, heading_offset);
     } else {
-        document_full(w, item, cx, level);
+        document_full(w, item, cx, heading_offset);
     }
 }
 
@@ -494,7 +494,7 @@ fn render_markdown(
     cx: &Context<'_>,
     md_text: &str,
     links: Vec<RenderedLink>,
-    heading_level: u32,
+    heading_offset: HeadingOffset,
 ) {
     let mut ids = cx.id_map.borrow_mut();
     write!(
@@ -507,7 +507,7 @@ fn render_markdown(
             error_codes: cx.shared.codes,
             edition: cx.shared.edition(),
             playground: &cx.shared.playground,
-            heading_level,
+            heading_offset,
         }
         .into_string()
     )
@@ -544,12 +544,22 @@ fn document_short(
     }
 }
 
-fn document_full_collapsible(w: &mut Buffer, item: &clean::Item, cx: &Context<'_>, level: u32) {
-    document_full_inner(w, item, cx, true, level);
+fn document_full_collapsible(
+    w: &mut Buffer,
+    item: &clean::Item,
+    cx: &Context<'_>,
+    heading_offset: HeadingOffset,
+) {
+    document_full_inner(w, item, cx, true, heading_offset);
 }
 
-fn document_full(w: &mut Buffer, item: &clean::Item, cx: &Context<'_>, level: u32) {
-    document_full_inner(w, item, cx, false, level);
+fn document_full(
+    w: &mut Buffer,
+    item: &clean::Item,
+    cx: &Context<'_>,
+    heading_offset: HeadingOffset,
+) {
+    document_full_inner(w, item, cx, false, heading_offset);
 }
 
 fn document_full_inner(
@@ -557,7 +567,7 @@ fn document_full_inner(
     item: &clean::Item,
     cx: &Context<'_>,
     is_collapsible: bool,
-    level: u32,
+    heading_offset: HeadingOffset,
 ) {
     if let Some(s) = cx.shared.maybe_collapsed_doc_value(item) {
         debug!("Doc block: =====\n{}\n=====", s);
@@ -568,10 +578,10 @@ fn document_full_inner(
                      <span>Expand description</span>\
                 </summary>",
             );
-            render_markdown(w, cx, &s, item.links(cx), level);
+            render_markdown(w, cx, &s, item.links(cx), heading_offset);
             w.write_str("</details>");
         } else {
-            render_markdown(w, cx, &s, item.links(cx), level);
+            render_markdown(w, cx, &s, item.links(cx), heading_offset);
         }
     }
 }
@@ -1340,7 +1350,7 @@ fn render_impl(
                         // because impls can't have a stability.
                         if item.doc_value().is_some() {
                             document_item_info(&mut info_buffer, cx, it, Some(parent));
-                            document_full(&mut doc_buffer, item, cx, 4);
+                            document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
                             short_documented = false;
                         } else {
                             // In case the item isn't documented,
@@ -1358,7 +1368,7 @@ fn render_impl(
                 } else {
                     document_item_info(&mut info_buffer, cx, item, Some(parent));
                     if rendering_params.show_def_docs {
-                        document_full(&mut doc_buffer, item, cx, 4);
+                        document_full(&mut doc_buffer, item, cx, HeadingOffset::H5);
                         short_documented = false;
                     }
                 }
@@ -1599,7 +1609,7 @@ fn render_impl(
                     error_codes: cx.shared.codes,
                     edition: cx.shared.edition(),
                     playground: &cx.shared.playground,
-                    heading_level: 1
+                    heading_offset: HeadingOffset::H2
                 }
                 .into_string()
             );
diff --git a/src/librustdoc/html/render/print_item.rs b/src/librustdoc/html/render/print_item.rs
index f26ee84569b..9b39a3eeaf0 100644
--- a/src/librustdoc/html/render/print_item.rs
+++ b/src/librustdoc/html/render/print_item.rs
@@ -30,7 +30,7 @@ use crate::html::format::{
 };
 use crate::html::highlight;
 use crate::html::layout::Page;
-use crate::html::markdown::MarkdownSummaryLine;
+use crate::html::markdown::{HeadingOffset, MarkdownSummaryLine};
 
 const ITEM_TABLE_OPEN: &'static str = "<div class=\"item-table\">";
 const ITEM_TABLE_CLOSE: &'static str = "</div>";
@@ -173,7 +173,7 @@ fn toggle_close(w: &mut Buffer) {
 }
 
 fn item_module(w: &mut Buffer, cx: &Context<'_>, item: &clean::Item, items: &[clean::Item]) {
-    document(w, cx, item, None, 1);
+    document(w, cx, item, None, HeadingOffset::H2);
 
     let mut indices = (0..items.len()).filter(|i| !items[*i].is_stripped()).collect::<Vec<usize>>();
 
@@ -485,7 +485,7 @@ fn item_function(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, f: &clean::
             notable_traits = notable_traits_decl(&f.decl, cx),
         );
     });
-    document(w, cx, it, None, 1)
+    document(w, cx, it, None, HeadingOffset::H2)
 }
 
 fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Trait) {
@@ -608,7 +608,7 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
     });
 
     // Trait documentation
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     fn write_small_section_header(w: &mut Buffer, id: &str, title: &str, extra_content: &str) {
         write!(
@@ -626,7 +626,7 @@ fn item_trait(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Tra
         let item_type = m.type_();
         let id = cx.derive_id(format!("{}.{}", item_type, name));
         let mut content = Buffer::empty_from(w);
-        document(&mut content, cx, m, Some(t), 4);
+        document(&mut content, cx, m, Some(t), HeadingOffset::H5);
         let toggled = !content.is_empty();
         if toggled {
             write!(w, "<details class=\"rustdoc-toggle\" open><summary>");
@@ -840,7 +840,7 @@ fn item_trait_alias(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clea
         );
     });
 
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     // Render any items associated directly to this alias, as otherwise they
     // won't be visible anywhere in the docs. It would be nice to also show
@@ -862,7 +862,7 @@ fn item_opaque_ty(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean:
         );
     });
 
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     // Render any items associated directly to this alias, as otherwise they
     // won't be visible anywhere in the docs. It would be nice to also show
@@ -893,7 +893,7 @@ fn item_typedef(
         );
     });
 
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     let def_id = it.def_id.expect_def_id();
     // Render any items associated directly to this alias, as otherwise they
@@ -911,7 +911,7 @@ fn item_union(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::Uni
         });
     });
 
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     let mut fields = s
         .fields
@@ -944,7 +944,7 @@ fn item_union(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::Uni
             if let Some(stability_class) = field.stability_class(cx.tcx()) {
                 write!(w, "<span class=\"stab {stab}\"></span>", stab = stability_class);
             }
-            document(w, cx, field, Some(it), 1);
+            document(w, cx, field, Some(it), HeadingOffset::H2);
         }
     }
     let def_id = it.def_id.expect_def_id();
@@ -1026,7 +1026,7 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
         });
     });
 
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     if !e.variants.is_empty() {
         write!(
@@ -1055,7 +1055,7 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
             w.write_str("</code>");
             render_stability_since(w, variant, it, cx.tcx());
             w.write_str("</div>");
-            document(w, cx, variant, Some(it), 1);
+            document(w, cx, variant, Some(it), HeadingOffset::H2);
             document_non_exhaustive(w, variant);
 
             use crate::clean::Variant;
@@ -1095,7 +1095,7 @@ fn item_enum(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, e: &clean::Enum
                                 f = field.name.as_ref().unwrap(),
                                 t = ty.print(cx)
                             );
-                            document(w, cx, field, Some(variant), 1);
+                            document(w, cx, field, Some(variant), HeadingOffset::H2);
                         }
                         _ => unreachable!(),
                     }
@@ -1122,7 +1122,7 @@ fn item_macro(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, t: &clean::Mac
             None,
         );
     });
-    document(w, cx, it, None, 1)
+    document(w, cx, it, None, HeadingOffset::H2)
 }
 
 fn item_proc_macro(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, m: &clean::ProcMacro) {
@@ -1152,11 +1152,11 @@ fn item_proc_macro(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, m: &clean
             });
         }
     }
-    document(w, cx, it, None, 1)
+    document(w, cx, it, None, HeadingOffset::H2)
 }
 
 fn item_primitive(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
     render_assoc_items(w, cx, it, it.def_id.expect_def_id(), AssocItemRender::All)
 }
 
@@ -1195,7 +1195,7 @@ fn item_constant(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, c: &clean::
         }
     });
 
-    document(w, cx, it, None, 1)
+    document(w, cx, it, None, HeadingOffset::H2)
 }
 
 fn item_struct(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::Struct) {
@@ -1206,7 +1206,7 @@ fn item_struct(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::St
         });
     });
 
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     let mut fields = s
         .fields
@@ -1242,7 +1242,7 @@ fn item_struct(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::St
                     name = field_name,
                     ty = ty.print(cx)
                 );
-                document(w, cx, field, Some(it), 1);
+                document(w, cx, field, Some(it), HeadingOffset::H2);
             }
         }
     }
@@ -1263,7 +1263,7 @@ fn item_static(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item, s: &clean::St
             typ = s.type_.print(cx)
         );
     });
-    document(w, cx, it, None, 1)
+    document(w, cx, it, None, HeadingOffset::H2)
 }
 
 fn item_foreign_type(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
@@ -1278,13 +1278,13 @@ fn item_foreign_type(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
         );
     });
 
-    document(w, cx, it, None, 1);
+    document(w, cx, it, None, HeadingOffset::H2);
 
     render_assoc_items(w, cx, it, it.def_id.expect_def_id(), AssocItemRender::All)
 }
 
 fn item_keyword(w: &mut Buffer, cx: &Context<'_>, it: &clean::Item) {
-    document(w, cx, it, None, 1)
+    document(w, cx, it, None, HeadingOffset::H2)
 }
 
 /// Compare two strings treating multi-digit numbers as single units (i.e. natural sort order).
diff --git a/src/librustdoc/markdown.rs b/src/librustdoc/markdown.rs
index 962712f5b91..47b24d40edc 100644
--- a/src/librustdoc/markdown.rs
+++ b/src/librustdoc/markdown.rs
@@ -10,7 +10,9 @@ use crate::config::{Options, RenderOptions};
 use crate::doctest::{Collector, TestOptions};
 use crate::html::escape::Escape;
 use crate::html::markdown;
-use crate::html::markdown::{find_testable_code, ErrorCodes, IdMap, Markdown, MarkdownWithToc};
+use crate::html::markdown::{
+    find_testable_code, ErrorCodes, HeadingOffset, IdMap, Markdown, MarkdownWithToc,
+};
 
 /// Separate any lines at the start of the file that begin with `# ` or `%`.
 fn extract_leading_metadata(s: &str) -> (Vec<&str>, &str) {
@@ -77,7 +79,7 @@ crate fn render<P: AsRef<Path>>(
             error_codes,
             edition,
             playground: &playground,
-            heading_level: 0,
+            heading_offset: HeadingOffset::H1,
         }
         .into_string()
     };
diff --git a/src/tools/error_index_generator/main.rs b/src/tools/error_index_generator/main.rs
index f89f28242a2..e7969349610 100644
--- a/src/tools/error_index_generator/main.rs
+++ b/src/tools/error_index_generator/main.rs
@@ -14,7 +14,7 @@ use std::path::PathBuf;
 
 use rustc_span::edition::DEFAULT_EDITION;
 
-use rustdoc::html::markdown::{ErrorCodes, IdMap, Markdown, Playground};
+use rustdoc::html::markdown::{ErrorCodes, HeadingOffset, IdMap, Markdown, Playground};
 
 pub struct ErrorMetadata {
     pub description: Option<String>,
@@ -126,7 +126,7 @@ impl Formatter for HTMLFormatter {
                         error_codes: ErrorCodes::Yes,
                         edition: DEFAULT_EDITION,
                         playground: &Some(playground),
-                        heading_level: 1
+                        heading_offset: HeadingOffset::H2,
                     }
                     .into_string()
                 )?
-- 
cgit 1.4.1-3-g733a5


From 1f86a8e2a058d7f12b25406a53576b08817677fe Mon Sep 17 00:00:00 2001
From: Mukund Lakshman <yaymukund@gmail.com>
Date: Wed, 6 Oct 2021 07:58:41 -0400
Subject: Revert the rustc_error_codes changes.

---
 compiler/rustc_error_codes/src/error_codes/E0001.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0002.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0007.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0009.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0014.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0073.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0074.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0087.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0088.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0089.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0090.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0110.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0136.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0137.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0139.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0154.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0162.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0165.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0193.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0205.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0211.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0243.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0244.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0251.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0256.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0281.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0297.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0301.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0302.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0303.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0329.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0383.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0386.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0387.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0388.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0389.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0398.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0399.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0439.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0447.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0448.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0497.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0504.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0595.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0619.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0633.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0665.md | 2 +-
 compiler/rustc_error_codes/src/error_codes/E0671.md | 2 +-
 src/tools/error_index_generator/main.rs             | 2 +-
 src/tools/tidy/src/error_codes_check.rs             | 4 ++--
 50 files changed, 51 insertions(+), 51 deletions(-)

(limited to 'src/tools/error_index_generator')

diff --git a/compiler/rustc_error_codes/src/error_codes/E0001.md b/compiler/rustc_error_codes/src/error_codes/E0001.md
index cd6e15f581f..90756780d15 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0001.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0001.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error suggests that the expression arm corresponding to the noted pattern
 will never be reached as for all possible values of the expression being
diff --git a/compiler/rustc_error_codes/src/error_codes/E0002.md b/compiler/rustc_error_codes/src/error_codes/E0002.md
index 4e7aa7fb9ed..5cb59da10e0 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0002.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0002.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error indicates that an empty match expression is invalid because the type
 it is matching on is non-empty (there exist values of this type). In safe code
diff --git a/compiler/rustc_error_codes/src/error_codes/E0007.md b/compiler/rustc_error_codes/src/error_codes/E0007.md
index d30de4af0eb..2c22b86af92 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0007.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0007.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error indicates that the bindings in a match arm would require a value to
 be moved into more than one location, thus violating unique ownership. Code
diff --git a/compiler/rustc_error_codes/src/error_codes/E0009.md b/compiler/rustc_error_codes/src/error_codes/E0009.md
index 6aab44cb4d6..aaabba04349 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0009.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0009.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 In a pattern, all values that don't implement the `Copy` trait have to be bound
 the same way. The goal here is to avoid binding simultaneously by-move and
diff --git a/compiler/rustc_error_codes/src/error_codes/E0014.md b/compiler/rustc_error_codes/src/error_codes/E0014.md
index 27ae8f09898..2c69957e9f6 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0014.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0014.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Constants can only be initialized by a constant value or, in a future
 version of Rust, a call to a const function. This error indicates the use
diff --git a/compiler/rustc_error_codes/src/error_codes/E0073.md b/compiler/rustc_error_codes/src/error_codes/E0073.md
index 39c16bc438f..a5aea86ff2d 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0073.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0073.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 You cannot define a struct (or enum) `Foo` that requires an instance of `Foo`
 in order to make a new `Foo` value. This is because there would be no way a
diff --git a/compiler/rustc_error_codes/src/error_codes/E0074.md b/compiler/rustc_error_codes/src/error_codes/E0074.md
index 026acac99e7..785d6de226d 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0074.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0074.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 When using the `#[simd]` attribute on a tuple struct, the components of the
 tuple struct must all be of a concrete, nongeneric type so the compiler can
diff --git a/compiler/rustc_error_codes/src/error_codes/E0087.md b/compiler/rustc_error_codes/src/error_codes/E0087.md
index cd2da0469bb..9d292186f0f 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0087.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0087.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Too many type arguments were supplied for a function. For example:
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0088.md b/compiler/rustc_error_codes/src/error_codes/E0088.md
index 6b565507ce4..7780ad5b56e 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0088.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0088.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 You gave too many lifetime arguments. Erroneous code example:
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0089.md b/compiler/rustc_error_codes/src/error_codes/E0089.md
index b78f95f266c..504fbc7b96a 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0089.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0089.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Too few type arguments were supplied for a function. For example:
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0090.md b/compiler/rustc_error_codes/src/error_codes/E0090.md
index 7b07a86dc25..e091bb6c9f2 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0090.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0090.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 You gave too few lifetime arguments. Example:
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0110.md b/compiler/rustc_error_codes/src/error_codes/E0110.md
index 91f599ff1dc..b9fe406ffb9 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0110.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0110.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 You tried to provide a lifetime to a type which doesn't need it.
 See `E0109` for more details.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0136.md b/compiler/rustc_error_codes/src/error_codes/E0136.md
index 0a74558e75b..15cf09a18cb 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0136.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0136.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 More than one `main` function was found.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0137.md b/compiler/rustc_error_codes/src/error_codes/E0137.md
index ba6f02add94..d4e19170f3f 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0137.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0137.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 More than one function was declared with the `#[main]` attribute.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0139.md b/compiler/rustc_error_codes/src/error_codes/E0139.md
index e7ad2a6f44d..a116cf29395 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0139.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0139.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 There are various restrictions on transmuting between types in Rust; for example
 types being transmuted must have the same size. To apply all these restrictions,
diff --git a/compiler/rustc_error_codes/src/error_codes/E0154.md b/compiler/rustc_error_codes/src/error_codes/E0154.md
index 9c954839eee..e437a71897c 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0154.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0154.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Imports (`use` statements) are not allowed after non-item statements, such as
 variable declarations and expression statements.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0162.md b/compiler/rustc_error_codes/src/error_codes/E0162.md
index 2e0f387e352..0161c9325c2 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0162.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0162.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 An `if let` pattern attempts to match the pattern, and enters the body if the
 match was successful. If the match is irrefutable (when it cannot fail to
diff --git a/compiler/rustc_error_codes/src/error_codes/E0165.md b/compiler/rustc_error_codes/src/error_codes/E0165.md
index 3222b7a87eb..7bcd6c0cbf3 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0165.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0165.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 A `while let` pattern attempts to match the pattern, and enters the body if the
 match was successful. If the match is irrefutable (when it cannot fail to
diff --git a/compiler/rustc_error_codes/src/error_codes/E0193.md b/compiler/rustc_error_codes/src/error_codes/E0193.md
index 6e7ebbaddf9..e29a949ffba 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0193.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0193.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 `where` clauses must use generic type parameters: it does not make sense to use
 them otherwise. An example causing this error:
diff --git a/compiler/rustc_error_codes/src/error_codes/E0205.md b/compiler/rustc_error_codes/src/error_codes/E0205.md
index 07bbd1f6834..7916f53ad3b 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0205.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0205.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 An attempt to implement the `Copy` trait for an enum failed because one of the
 variants does not implement `Copy`. To fix this, you must implement `Copy` for
diff --git a/compiler/rustc_error_codes/src/error_codes/E0211.md b/compiler/rustc_error_codes/src/error_codes/E0211.md
index 2485367e097..77289f01900 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0211.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0211.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 You used a function or type which doesn't fit the requirements for where it was
 used. Erroneous code examples:
diff --git a/compiler/rustc_error_codes/src/error_codes/E0243.md b/compiler/rustc_error_codes/src/error_codes/E0243.md
index ef4a837ec21..5d3d1828bf5 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0243.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0243.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error indicates that not enough type parameters were found in a type or
 trait.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0244.md b/compiler/rustc_error_codes/src/error_codes/E0244.md
index 31c5b4542e2..5187b7b05d2 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0244.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0244.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error indicates that too many type parameters were found in a type or
 trait.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0251.md b/compiler/rustc_error_codes/src/error_codes/E0251.md
index 7b048db5ece..4121dd27877 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0251.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0251.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Two items of the same name cannot be imported without rebinding one of the
 items under a new local name.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0256.md b/compiler/rustc_error_codes/src/error_codes/E0256.md
index 1b518b1615b..385376cdade 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0256.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0256.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 You can't import a type or module when the name of the item being imported is
 the same as another type or submodule defined in the module.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0281.md b/compiler/rustc_error_codes/src/error_codes/E0281.md
index 2d8ead0b018..1d7904b67dd 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0281.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0281.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 You tried to supply a type which doesn't implement some trait in a location
 which expected that trait. This error typically occurs when working with
diff --git a/compiler/rustc_error_codes/src/error_codes/E0297.md b/compiler/rustc_error_codes/src/error_codes/E0297.md
index 001e0f3089e..66c31376d8b 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0297.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0297.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Patterns used to bind names must be irrefutable. That is, they must guarantee
 that a name will be extracted in all cases. Instead of pattern matching the
diff --git a/compiler/rustc_error_codes/src/error_codes/E0301.md b/compiler/rustc_error_codes/src/error_codes/E0301.md
index 7b1e02051dc..485e19fbb8d 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0301.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0301.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Mutable borrows are not allowed in pattern guards, because matching cannot have
 side effects. Side effects could alter the matched object or the environment
diff --git a/compiler/rustc_error_codes/src/error_codes/E0302.md b/compiler/rustc_error_codes/src/error_codes/E0302.md
index c56500fcebc..e6ac9d590c8 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0302.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0302.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Assignments are not allowed in pattern guards, because matching cannot have
 side effects. Side effects could alter the matched object or the environment
diff --git a/compiler/rustc_error_codes/src/error_codes/E0303.md b/compiler/rustc_error_codes/src/error_codes/E0303.md
index 750b766f5bf..459906047cc 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0303.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0303.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Sub-bindings, e.g. `ref x @ Some(ref y)` are now allowed under
 `#![feature(bindings_after_at)]` and checked to make sure that
diff --git a/compiler/rustc_error_codes/src/error_codes/E0329.md b/compiler/rustc_error_codes/src/error_codes/E0329.md
index 36114316e88..37d84a1a89b 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0329.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0329.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 An attempt was made to access an associated constant through either a generic
 type parameter or `Self`. This is not supported yet. An example causing this
diff --git a/compiler/rustc_error_codes/src/error_codes/E0383.md b/compiler/rustc_error_codes/src/error_codes/E0383.md
index 309eb2b59eb..fd2b0b08fb0 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0383.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0383.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error occurs when an attempt is made to partially reinitialize a
 structure that is currently uninitialized.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0386.md b/compiler/rustc_error_codes/src/error_codes/E0386.md
index 5e45a2b40ce..de3b468b6e4 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0386.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0386.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error occurs when an attempt is made to mutate the target of a mutable
 reference stored inside an immutable container.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0387.md b/compiler/rustc_error_codes/src/error_codes/E0387.md
index ddc838bdca1..38ad19bd6aa 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0387.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0387.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error occurs when an attempt is made to mutate or mutably reference data
 that a closure has captured immutably.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0388.md b/compiler/rustc_error_codes/src/error_codes/E0388.md
index 13ef94a4855..512fb42e6ec 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0388.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0388.md
@@ -1 +1 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0389.md b/compiler/rustc_error_codes/src/error_codes/E0389.md
index 19bb6ec4081..9f064e44c82 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0389.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0389.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 An attempt was made to mutate data using a non-mutable reference. This
 commonly occurs when attempting to assign to a non-mutable reference of a
diff --git a/compiler/rustc_error_codes/src/error_codes/E0398.md b/compiler/rustc_error_codes/src/error_codes/E0398.md
index 12e0eb1a5d5..75d86979e3c 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0398.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0398.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 In Rust 1.3, the default object lifetime bounds are expected to change, as
 described in [RFC 1156]. You are getting a warning because the compiler
diff --git a/compiler/rustc_error_codes/src/error_codes/E0399.md b/compiler/rustc_error_codes/src/error_codes/E0399.md
index c3e9616c606..6ea6054b417 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0399.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0399.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler
+#### Note: this error code is no longer emitted by the compiler
 
 You implemented a trait, overriding one or more of its associated types but did
 not reimplement its default methods.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0439.md b/compiler/rustc_error_codes/src/error_codes/E0439.md
index 85e965c4eee..24268aef222 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0439.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0439.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 The length of the platform-intrinsic function `simd_shuffle` wasn't specified.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0447.md b/compiler/rustc_error_codes/src/error_codes/E0447.md
index e880ff4637d..af8cd8d6d52 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0447.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0447.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 The `pub` keyword was used inside a function.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0448.md b/compiler/rustc_error_codes/src/error_codes/E0448.md
index f4bd1841888..ba096f9e984 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0448.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0448.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 The `pub` keyword was used inside a public enum.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0497.md b/compiler/rustc_error_codes/src/error_codes/E0497.md
index 12004996384..ef2882415d2 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0497.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0497.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 A stability attribute was used outside of the standard library.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0504.md b/compiler/rustc_error_codes/src/error_codes/E0504.md
index 640cfad656f..bcbd00a8690 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0504.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0504.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 This error occurs when an attempt is made to move a borrowed variable into a
 closure.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0595.md b/compiler/rustc_error_codes/src/error_codes/E0595.md
index 96fbb5e410a..e6729013243 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0595.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0595.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Closures cannot mutate immutable captured variables.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0619.md b/compiler/rustc_error_codes/src/error_codes/E0619.md
index d33154058dd..f516de43095 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0619.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0619.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 The type-checker needed to know the type of an expression, but that type had not
 yet been inferred.
diff --git a/compiler/rustc_error_codes/src/error_codes/E0633.md b/compiler/rustc_error_codes/src/error_codes/E0633.md
index f6e8a4042ed..5b6c15c82eb 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0633.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0633.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 The `unwind` attribute was malformed.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0665.md b/compiler/rustc_error_codes/src/error_codes/E0665.md
index db5e088cc50..ae54d6d1579 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0665.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0665.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 The `Default` trait was derived on an enum.
 
diff --git a/compiler/rustc_error_codes/src/error_codes/E0671.md b/compiler/rustc_error_codes/src/error_codes/E0671.md
index a68273f752e..d4dbfb7a5d8 100644
--- a/compiler/rustc_error_codes/src/error_codes/E0671.md
+++ b/compiler/rustc_error_codes/src/error_codes/E0671.md
@@ -1,4 +1,4 @@
-### Note: this error code is no longer emitted by the compiler.
+#### Note: this error code is no longer emitted by the compiler.
 
 Const parameters cannot depend on type parameters.
 The following is therefore invalid:
diff --git a/src/tools/error_index_generator/main.rs b/src/tools/error_index_generator/main.rs
index e7969349610..5b3da5893ea 100644
--- a/src/tools/error_index_generator/main.rs
+++ b/src/tools/error_index_generator/main.rs
@@ -126,7 +126,7 @@ impl Formatter for HTMLFormatter {
                         error_codes: ErrorCodes::Yes,
                         edition: DEFAULT_EDITION,
                         playground: &Some(playground),
-                        heading_offset: HeadingOffset::H2,
+                        heading_offset: HeadingOffset::H1,
                     }
                     .into_string()
                 )?
diff --git a/src/tools/tidy/src/error_codes_check.rs b/src/tools/tidy/src/error_codes_check.rs
index ae169d383b2..53c75a46339 100644
--- a/src/tools/tidy/src/error_codes_check.rs
+++ b/src/tools/tidy/src/error_codes_check.rs
@@ -49,7 +49,7 @@ fn check_error_code_explanation(
             } else if s.contains("compile-fail") {
                 invalid_compile_fail_format = true;
             }
-        } else if s.starts_with("### Note: this error code is no longer emitted by the compiler") {
+        } else if s.starts_with("#### Note: this error code is no longer emitted by the compiler") {
             if !found_error_code {
                 error_codes.get_mut(&err_code).map(|x| x.has_test = true);
                 found_error_code = true;
@@ -64,7 +64,7 @@ fn check_if_error_code_is_test_in_explanation(f: &str, err_code: &str) -> bool {
 
     for line in f.lines() {
         let s = line.trim();
-        if s.starts_with("### Note: this error code is no longer emitted by the compiler") {
+        if s.starts_with("#### Note: this error code is no longer emitted by the compiler") {
             return true;
         }
         if s.starts_with("```") {
-- 
cgit 1.4.1-3-g733a5