Rollup merge of #131908 - aDotInTheVoid:rustdoc-gamer-hashing, r=notr…

…iddle,GuillaumeGomez

rustdoc: Switch from FxHash to sha256 for static file hashing.

Fixes #129533 (comment)

fxhash isn't well defined, and it's implementation is being changed in #129533. But because rustdoc uses it for static files (and encodes that hashing in rustdoc.css), this broke our tests. Given that this isn't performace critical, I think the right fix is to used a well-defined hash that will never change its definition. I've picked (rather arbitrarily) sha256.

Cargo.lock

@@ -4584,6 +4584,7 @@ dependencies = [
  "rustdoc-json-types",
  "serde",
  "serde_json",
+ "sha2",
  "smallvec",
  "tempfile",
  "threadpool",

src/librustdoc/Cargo.toml

@@ -24,6 +24,7 @@ tracing = "0.1"
 tracing-tree = "0.3.0"
 threadpool = "1.8.1"
 unicode-segmentation = "1.9"
+sha2 = "0.10.8"
 
 [dependencies.tracing-subscriber]
 version = "0.3.3"

src/librustdoc/html/static/css/rustdoc.css

@@ -44,15 +44,15 @@ xmlns="http://www.w3.org/2000/svg" fill="black" height="18px">\
 	font-style: normal;
 	font-weight: 400;
 	src: local('Fira Sans'),
-		url("FiraSans-Regular-018c141bf0843ffd.woff2") format("woff2");
+		url("FiraSans-Regular-0fe48ade.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
 	font-family: 'Fira Sans';
 	font-style: normal;
 	font-weight: 500;
 	src: local('Fira Sans Medium'),
-		url("FiraSans-Medium-8f9a781e4970d388.woff2") format("woff2");
+		url("FiraSans-Medium-e1aa3f0a.woff2") format("woff2");
 	font-display: swap;
 }
 
@@ -62,23 +62,23 @@ xmlns="http://www.w3.org/2000/svg" fill="black" height="18px">\
 	font-style: normal;
 	font-weight: 400;
 	src: local('Source Serif 4'),
-		url("SourceSerif4-Regular-46f98efaafac5295.ttf.woff2") format("woff2");
+		url("SourceSerif4-Regular-6b053e98.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
 	font-family: 'Source Serif 4';
 	font-style: italic;
 	font-weight: 400;
 	src: local('Source Serif 4 Italic'),
-		url("SourceSerif4-It-acdfaf1a8af734b1.ttf.woff2") format("woff2");
+		url("SourceSerif4-It-ca3b17ed.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
 	font-family: 'Source Serif 4';
 	font-style: normal;
 	font-weight: 700;
 	src: local('Source Serif 4 Bold'),
-		url("SourceSerif4-Bold-a2c9cd1067f8b328.ttf.woff2") format("woff2");
+		url("SourceSerif4-Bold-6d4fd4c0.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 
@@ -89,28 +89,28 @@ xmlns="http://www.w3.org/2000/svg" fill="black" height="18px">\
 	font-weight: 400;
 	/* Avoid using locally installed font because bad versions are in circulation:
 	 * see https://github.com/rust-lang/rust/issues/24355 */
-	src: url("SourceCodePro-Regular-562dcc5011b6de7d.ttf.woff2") format("woff2");
+	src: url("SourceCodePro-Regular-8badfe75.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
 	font-family: 'Source Code Pro';
 	font-style: italic;
 	font-weight: 400;
-	src: url("SourceCodePro-It-1cc31594bf4f1f79.ttf.woff2") format("woff2");
+	src: url("SourceCodePro-It-fc8b9304.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 @font-face {
 	font-family: 'Source Code Pro';
 	font-style: normal;
 	font-weight: 600;
-	src: url("SourceCodePro-Semibold-d899c5a5c4aeb14a.ttf.woff2") format("woff2");
+	src: url("SourceCodePro-Semibold-aa29a496.ttf.woff2") format("woff2");
 	font-display: swap;
 }
 
 /* Avoid using legacy CJK serif fonts in Windows like Batang. */
 @font-face {
 	font-family: 'NanumBarunGothic';
-	src: url("NanumBarunGothic-0f09457c7a19b7c6.ttf.woff2") format("woff2");
+	src: url("NanumBarunGothic-13b3dcba.ttf.woff2") format("woff2");
 	font-display: swap;
 	unicode-range: U+AC00-D7AF, U+1100-11FF, U+3130-318F, U+A960-A97F, U+D7B0-D7FF;
 }

src/librustdoc/html/static_files.rs

@@ -3,12 +3,9 @@
 //! All the static files are included here for centralized access in case anything other than the
 //! HTML rendering code (say, the theme checker) needs to access one of these files.
 
-use std::hash::Hasher;
 use std::path::{Path, PathBuf};
 use std::{fmt, str};
 
-use rustc_data_structures::fx::FxHasher;
-
 pub(crate) struct StaticFile {
     pub(crate) filename: PathBuf,
     pub(crate) bytes: &'static [u8],
@@ -64,9 +61,11 @@ pub(crate) fn static_filename(filename: &str, contents: &[u8]) -> PathBuf {
 }
 
 fn static_suffix(bytes: &[u8]) -> String {
-    let mut hasher = FxHasher::default();
-    hasher.write(bytes);
-    format!("-{:016x}", hasher.finish())
+    use sha2::Digest;
+    let bytes = sha2::Sha256::digest(bytes);
+    let mut digest = format!("-{bytes:x}");
+    digest.truncate(9);
+    digest
 }
 
 macro_rules! static_files {