diff --git a/src/librustdoc/clean/cfg.rs b/src/librustdoc/clean/cfg.rs
index c039b181178a4..9ab873d711f3c 100644
--- a/src/librustdoc/clean/cfg.rs
+++ b/src/librustdoc/clean/cfg.rs
@@ -16,9 +16,6 @@ use rustc_span::Span;
 
 use crate::html::escape::Escape;
 
-#[cfg(test)]
-mod tests;
-
 #[derive(Clone, Debug, PartialEq, Eq, Hash)]
 pub enum Cfg {
     /// Accepts all configurations.
diff --git a/src/librustdoc/doctest.rs b/src/librustdoc/doctest.rs
index 7b7c152d8abbf..a856c250bf462 100644
--- a/src/librustdoc/doctest.rs
+++ b/src/librustdoc/doctest.rs
@@ -1034,6 +1034,3 @@ impl<'a, 'hir, 'tcx> intravisit::Visitor<'hir> for HirCollector<'a, 'hir, 'tcx>
         );
     }
 }
-
-#[cfg(test)]
-mod tests;
diff --git a/src/librustdoc/html/highlight.rs b/src/librustdoc/html/highlight.rs
index 4769edc50ff07..909f0c4804426 100644
--- a/src/librustdoc/html/highlight.rs
+++ b/src/librustdoc/html/highlight.rs
@@ -45,7 +45,7 @@ fn write_header(out: &mut String, class: Option<&str>) {
         .unwrap()
 }
 
-fn write_code(out: &mut String, src: &str) {
+crate fn write_code(out: &mut String, src: &str) {
     Classifier::new(src).highlight(&mut |highlight| {
         match highlight {
             Highlight::Token { text, class } => string(out, Escape(text), class),
@@ -343,6 +343,3 @@ fn string<T: Display>(out: &mut String, text: T, klass: Class) {
         klass => write!(out, "<span class=\"{}\">{}</span>", klass.as_html(), text).unwrap(),
     }
 }
-
-#[cfg(test)]
-mod tests;
diff --git a/src/librustdoc/html/markdown.rs b/src/librustdoc/html/markdown.rs
index d54b8ea747899..b20f4c70fcd18 100644
--- a/src/librustdoc/html/markdown.rs
+++ b/src/librustdoc/html/markdown.rs
@@ -40,9 +40,6 @@ use crate::html::toc::TocBuilder;
 
 use pulldown_cmark::{html, CodeBlockKind, CowStr, Event, Options, Parser, Tag};
 
-#[cfg(test)]
-mod tests;
-
 fn opts() -> Options {
     Options::ENABLE_TABLES | Options::ENABLE_FOOTNOTES | Options::ENABLE_STRIKETHROUGH
 }
@@ -678,6 +675,10 @@ impl<'a, 'b> ExtraInfo<'a, 'b> {
 
 #[derive(Eq, PartialEq, Clone, Debug)]
 pub struct LangString {
+    #[cfg(test)]
+    // Only making it public when running tests.
+    pub original: String,
+    #[cfg(not(test))]
     original: String,
     pub should_panic: bool,
     pub no_run: bool,
@@ -698,7 +699,7 @@ pub enum Ignore {
 }
 
 impl LangString {
-    fn all_false() -> LangString {
+    pub fn all_false() -> LangString {
         LangString {
             original: String::new(),
             should_panic: false,
@@ -713,7 +714,7 @@ impl LangString {
         }
     }
 
-    fn parse_without_check(
+    pub fn parse_without_check(
         string: &str,
         allow_error_code_check: ErrorCodes,
         enable_per_target_ignores: bool,
@@ -721,7 +722,7 @@ impl LangString {
         Self::parse(string, allow_error_code_check, enable_per_target_ignores, None)
     }
 
-    fn parse(
+    pub fn parse(
         string: &str,
         allow_error_code_check: ErrorCodes,
         enable_per_target_ignores: bool,
diff --git a/src/librustdoc/html/mod.rs b/src/librustdoc/html/mod.rs
index 367538d440ea1..8f7552d0936b9 100644
--- a/src/librustdoc/html/mod.rs
+++ b/src/librustdoc/html/mod.rs
@@ -4,6 +4,6 @@ crate mod highlight;
 crate mod layout;
 pub mod markdown;
 pub mod render;
-crate mod sources;
+pub mod sources;
 crate mod static_files;
-crate mod toc;
+pub mod toc;
diff --git a/src/librustdoc/html/render/mod.rs b/src/librustdoc/html/render/mod.rs
index 470e9d5ae768d..779488c285aa8 100644
--- a/src/librustdoc/html/render/mod.rs
+++ b/src/librustdoc/html/render/mod.rs
@@ -27,9 +27,6 @@
 
 pub mod cache;
 
-#[cfg(test)]
-mod tests;
-
 use std::borrow::Cow;
 use std::cell::{Cell, RefCell};
 use std::cmp::Ordering;
diff --git a/src/librustdoc/html/toc.rs b/src/librustdoc/html/toc.rs
index 721988e29a678..eb45926a67719 100644
--- a/src/librustdoc/html/toc.rs
+++ b/src/librustdoc/html/toc.rs
@@ -16,7 +16,7 @@ pub struct Toc {
     /// ### A
     /// ## B
     /// ```
-    entries: Vec<TocEntry>,
+    pub(crate) entries: Vec<TocEntry>,
 }
 
 impl Toc {
@@ -27,11 +27,11 @@ impl Toc {
 
 #[derive(Debug, PartialEq)]
 pub struct TocEntry {
-    level: u32,
-    sec_number: String,
-    name: String,
-    id: String,
-    children: Toc,
+    pub(crate) level: u32,
+    pub(crate) sec_number: String,
+    pub(crate) name: String,
+    pub(crate) id: String,
+    pub(crate) children: Toc,
 }
 
 /// Progressive construction of a table of contents.
@@ -183,6 +183,3 @@ impl Toc {
         v
     }
 }
-
-#[cfg(test)]
-mod tests;
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 73a783d54060c..8632a7a9a243f 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -37,7 +37,7 @@ extern crate rustc_mir;
 extern crate rustc_parse;
 extern crate rustc_resolve;
 extern crate rustc_session;
-extern crate rustc_span as rustc_span;
+extern crate rustc_span;
 extern crate rustc_target;
 extern crate rustc_trait_selection;
 extern crate rustc_typeck;
@@ -57,21 +57,24 @@ use rustc_session::{early_error, early_warn};
 #[macro_use]
 mod externalfiles;
 
-mod clean;
+#[cfg(test)]
+mod rustdoc_tests;
+
+crate mod clean;
 mod config;
 mod core;
 mod docfs;
 mod doctree;
 #[macro_use]
 mod error;
-mod doctest;
+crate mod doctest;
 mod fold;
 crate mod formats;
 pub mod html;
 mod json;
 mod markdown;
-mod passes;
-mod theme;
+crate mod passes;
+crate mod theme;
 mod visit_ast;
 mod visit_lib;
 
diff --git a/src/librustdoc/passes/mod.rs b/src/librustdoc/passes/mod.rs
index 75a659666673f..9c143c0cc8ba2 100644
--- a/src/librustdoc/passes/mod.rs
+++ b/src/librustdoc/passes/mod.rs
@@ -24,7 +24,7 @@ pub use self::strip_private::STRIP_PRIVATE;
 mod strip_priv_imports;
 pub use self::strip_priv_imports::STRIP_PRIV_IMPORTS;
 
-mod unindent_comments;
+crate mod unindent_comments;
 pub use self::unindent_comments::UNINDENT_COMMENTS;
 
 mod propagate_doc_cfg;
diff --git a/src/librustdoc/passes/unindent_comments.rs b/src/librustdoc/passes/unindent_comments.rs
index 5604a9c2dc163..2064f29c36abf 100644
--- a/src/librustdoc/passes/unindent_comments.rs
+++ b/src/librustdoc/passes/unindent_comments.rs
@@ -6,16 +6,13 @@ use crate::core::DocContext;
 use crate::fold::{self, DocFolder};
 use crate::passes::Pass;
 
-#[cfg(test)]
-mod tests;
-
 pub const UNINDENT_COMMENTS: Pass = Pass {
     name: "unindent-comments",
     run: unindent_comments,
     description: "removes excess indentation on comments in order for markdown to like it",
 };
 
-pub fn unindent_comments(krate: clean::Crate, _: &DocContext<'_>) -> clean::Crate {
+crate fn unindent_comments(krate: clean::Crate, _: &DocContext<'_>) -> clean::Crate {
     CommentCleaner.fold_crate(krate)
 }
 
@@ -46,7 +43,7 @@ fn unindent_fragments(docs: &mut Vec<DocFragment>) {
     }
 }
 
-fn unindent(s: &str) -> String {
+crate fn unindent(s: &str) -> String {
     let lines = s.lines().collect::<Vec<&str>>();
     let mut saw_first_line = false;
     let mut saw_second_line = false;
diff --git a/src/librustdoc/clean/cfg/tests.rs b/src/librustdoc/rustdoc_tests/clean_cfg.rs
similarity index 99%
rename from src/librustdoc/clean/cfg/tests.rs
rename to src/librustdoc/rustdoc_tests/clean_cfg.rs
index 794a7bcaf1cb7..de48d03e94b5a 100644
--- a/src/librustdoc/clean/cfg/tests.rs
+++ b/src/librustdoc/rustdoc_tests/clean_cfg.rs
@@ -1,7 +1,7 @@
-use super::*;
+use crate::clean::cfg::Cfg;
 
 use rustc_ast::attr;
-use rustc_ast::Path;
+use rustc_ast::{LitKind, MetaItem, MetaItemKind, NestedMetaItem, Path};
 use rustc_span::symbol::{Ident, Symbol};
 use rustc_span::with_default_session_globals;
 use rustc_span::DUMMY_SP;
diff --git a/src/librustdoc/doctest/tests.rs b/src/librustdoc/rustdoc_tests/doctest.rs
similarity index 99%
rename from src/librustdoc/doctest/tests.rs
rename to src/librustdoc/rustdoc_tests/doctest.rs
index a96186a95e16b..b27ce2d3501ba 100644
--- a/src/librustdoc/doctest/tests.rs
+++ b/src/librustdoc/rustdoc_tests/doctest.rs
@@ -1,5 +1,5 @@
-use super::{make_test, TestOptions};
 use rustc_span::edition::DEFAULT_EDITION;
+use crate::doctest::{make_test, TestOptions};
 
 #[test]
 fn make_test_basic() {
diff --git a/src/librustdoc/html/highlight/fixtures/sample.html b/src/librustdoc/rustdoc_tests/fixtures/sample.html
similarity index 100%
rename from src/librustdoc/html/highlight/fixtures/sample.html
rename to src/librustdoc/rustdoc_tests/fixtures/sample.html
diff --git a/src/librustdoc/html/highlight/fixtures/sample.rs b/src/librustdoc/rustdoc_tests/fixtures/sample.rs
similarity index 100%
rename from src/librustdoc/html/highlight/fixtures/sample.rs
rename to src/librustdoc/rustdoc_tests/fixtures/sample.rs
diff --git a/src/librustdoc/html/highlight/tests.rs b/src/librustdoc/rustdoc_tests/html_highlight.rs
similarity index 94%
rename from src/librustdoc/html/highlight/tests.rs
rename to src/librustdoc/rustdoc_tests/html_highlight.rs
index c79471b1fae6b..1de4c5805fbc2 100644
--- a/src/librustdoc/html/highlight/tests.rs
+++ b/src/librustdoc/rustdoc_tests/html_highlight.rs
@@ -1,5 +1,5 @@
-use super::write_code;
 use expect_test::expect_file;
+use crate::html::highlight::write_code;
 
 #[test]
 fn test_html_highlighting() {
diff --git a/src/librustdoc/html/markdown/tests.rs b/src/librustdoc/rustdoc_tests/html_markdown.rs
similarity index 98%
rename from src/librustdoc/html/markdown/tests.rs
rename to src/librustdoc/rustdoc_tests/html_markdown.rs
index 01a897c93db8d..c8ef420318dfe 100644
--- a/src/librustdoc/html/markdown/tests.rs
+++ b/src/librustdoc/rustdoc_tests/html_markdown.rs
@@ -1,5 +1,5 @@
-use super::plain_summary_line;
-use super::{ErrorCodes, IdMap, Ignore, LangString, Markdown, MarkdownHtml};
+use crate::html::markdown::plain_summary_line;
+use crate::html::markdown::{ErrorCodes, IdMap, Ignore, LangString, Markdown, MarkdownHtml};
 use rustc_span::edition::{Edition, DEFAULT_EDITION};
 use std::cell::RefCell;
 
diff --git a/src/librustdoc/html/render/tests.rs b/src/librustdoc/rustdoc_tests/html_render.rs
similarity index 95%
rename from src/librustdoc/html/render/tests.rs
rename to src/librustdoc/rustdoc_tests/html_render.rs
index abf5f05fe58ab..12a80a3e6017e 100644
--- a/src/librustdoc/html/render/tests.rs
+++ b/src/librustdoc/rustdoc_tests/html_render.rs
@@ -1,4 +1,5 @@
-use super::*;
+use crate::html::render::compare_names;
+use std::cmp::Ordering;
 
 #[test]
 fn test_compare_names() {
diff --git a/src/librustdoc/html/toc/tests.rs b/src/librustdoc/rustdoc_tests/html_toc.rs
similarity index 97%
rename from src/librustdoc/html/toc/tests.rs
rename to src/librustdoc/rustdoc_tests/html_toc.rs
index 014f346862b3f..64f0f14f22d2d 100644
--- a/src/librustdoc/html/toc/tests.rs
+++ b/src/librustdoc/rustdoc_tests/html_toc.rs
@@ -1,4 +1,4 @@
-use super::{Toc, TocBuilder, TocEntry};
+use crate::html::toc::{Toc, TocBuilder, TocEntry};
 
 #[test]
 fn builder_smoke() {
diff --git a/src/librustdoc/rustdoc_tests/mod.rs b/src/librustdoc/rustdoc_tests/mod.rs
new file mode 100644
index 0000000000000..4bf855ba896f8
--- /dev/null
+++ b/src/librustdoc/rustdoc_tests/mod.rs
@@ -0,0 +1,16 @@
+#[cfg(test)]
+mod clean_cfg;
+#[cfg(test)]
+mod doctest;
+#[cfg(test)]
+mod html_highlight;
+#[cfg(test)]
+mod html_markdown;
+#[cfg(test)]
+mod html_render;
+#[cfg(test)]
+mod html_toc;
+#[cfg(test)]
+mod passes_unindent_comments;
+#[cfg(test)]
+mod theme;
diff --git a/src/librustdoc/passes/unindent_comments/tests.rs b/src/librustdoc/rustdoc_tests/passes_unindent_comments.rs
similarity index 97%
rename from src/librustdoc/passes/unindent_comments/tests.rs
rename to src/librustdoc/rustdoc_tests/passes_unindent_comments.rs
index c39c03e1249c6..b7d976823ea27 100644
--- a/src/librustdoc/passes/unindent_comments/tests.rs
+++ b/src/librustdoc/rustdoc_tests/passes_unindent_comments.rs
@@ -1,4 +1,4 @@
-use super::*;
+use crate::passes::unindent_comments::*;
 
 #[test]
 fn should_unindent() {
diff --git a/src/librustdoc/theme/tests.rs b/src/librustdoc/rustdoc_tests/theme.rs
similarity index 98%
rename from src/librustdoc/theme/tests.rs
rename to src/librustdoc/rustdoc_tests/theme.rs
index b924215733d55..22c68811001c4 100644
--- a/src/librustdoc/theme/tests.rs
+++ b/src/librustdoc/rustdoc_tests/theme.rs
@@ -1,4 +1,4 @@
-use super::*;
+use crate::theme::*;
 
 #[test]
 fn test_comments_in_rules() {
diff --git a/src/librustdoc/theme.rs b/src/librustdoc/theme.rs
index c8eb271c807d6..1d42d06965df3 100644
--- a/src/librustdoc/theme.rs
+++ b/src/librustdoc/theme.rs
@@ -5,9 +5,6 @@ use std::path::Path;
 
 use rustc_errors::Handler;
 
-#[cfg(test)]
-mod tests;
-
 #[derive(Debug, Clone, Eq)]
 pub struct CssPath {
     pub name: String,
@@ -43,14 +40,14 @@ impl Hash for CssPath {
 }
 
 impl CssPath {
-    fn new(name: String) -> CssPath {
+    pub fn new(name: String) -> CssPath {
         CssPath { name, children: FxHashSet::default() }
     }
 }
 
 /// All variants contain the position they occur.
 #[derive(Debug, Clone, Copy)]
-enum Events {
+pub enum Events {
     StartLineComment(usize),
     StartComment(usize),
     EndComment(usize),
@@ -59,7 +56,7 @@ enum Events {
 }
 
 impl Events {
-    fn get_pos(&self) -> usize {
+    pub fn get_pos(&self) -> usize {
         match *self {
             Events::StartLineComment(p)
             | Events::StartComment(p)
@@ -69,7 +66,7 @@ impl Events {
         }
     }
 
-    fn is_comment(&self) -> bool {
+    pub fn is_comment(&self) -> bool {
         match *self {
             Events::StartLineComment(_) | Events::StartComment(_) | Events::EndComment(_) => true,
             _ => false,
@@ -88,7 +85,7 @@ fn is_line_comment(pos: usize, v: &[u8], events: &[Events]) -> bool {
     v[pos + 1] == b'/'
 }
 
-fn load_css_events(v: &[u8]) -> Vec<Events> {
+pub fn load_css_events(v: &[u8]) -> Vec<Events> {
     let mut pos = 0;
     let mut events = Vec::with_capacity(100);