Improve performance of scanning source files

CHANGELOG.md

@@ -7,7 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-- Nothing yet!
+### Fixed
+
+- Improve performance of scanning source files ([#15270](https://github.com/tailwindlabs/tailwindcss/pull/15270))
 
 ## [4.0.0-beta.4] - 2024-11-29
 

crates/oxide/src/lib.rs

@@ -102,13 +102,11 @@ impl Scanner {
     pub fn scan(&mut self) -> Vec<String> {
         init_tracing();
         self.prepare();
-        self.check_for_new_files();
         self.compute_candidates();
 
-        let mut candidates: Vec<String> = self.candidates.clone().into_iter().collect();
-
-        candidates.sort();
+        let mut candidates: Vec<String> = self.candidates.clone().into_par_iter().collect();
 
+        candidates.par_sort();
         candidates
     }
 
@@ -140,7 +138,7 @@ impl Scanner {
         let extractor = Extractor::with_positions(&content[..], Default::default());
 
         let candidates: Vec<(String, usize)> = extractor
-            .into_iter()
+            .into_par_iter()
             .map(|(s, i)| {
                 // SAFETY: When we parsed the candidates, we already guaranteed that the byte slices
                 // are valid, therefore we don't have to re-check here when we want to convert it back
@@ -156,7 +154,7 @@ impl Scanner {
         self.prepare();
 
         self.files
-            .iter()
+            .par_iter()
             .filter_map(|x| Path::from(x.clone()).canonicalize().ok())
             .map(|x| x.to_string())
             .collect()
@@ -201,14 +199,15 @@ impl Scanner {
 
         if !changed_content.is_empty() {
             let candidates = parse_all_blobs(read_all_files(changed_content));
-            self.candidates.extend(candidates);
+            self.candidates.par_extend(candidates);
         }
     }
 
     // Ensures that all files/globs are resolved and the scanner is ready to scan
     // content for candidates.
     fn prepare(&mut self) {
         if self.ready {
+            self.check_for_new_files();
             return;
         }
 
@@ -455,12 +454,10 @@ fn read_all_files(changed_content: Vec<ChangedContent>) -> Vec<Vec<u8>> {
 
 #[tracing::instrument(skip_all)]
 fn parse_all_blobs(blobs: Vec<Vec<u8>>) -> Vec<String> {
-    let input: Vec<_> = blobs.iter().map(|blob| &blob[..]).collect();
-    let input = &input[..];
-
-    let mut result: Vec<String> = input
+    let mut result: Vec<_> = blobs
         .par_iter()
-        .map(|input| Extractor::unique(input, Default::default()))
+        .flat_map(|blob| blob.par_split(|x| matches!(x, b'\n')))
+        .map(|blob| Extractor::unique(blob, Default::default()))
         .reduce(Default::default, |mut a, b| {
             a.extend(b);
             a
@@ -473,6 +470,7 @@ fn parse_all_blobs(blobs: Vec<Vec<u8>>) -> Vec<String> {
             unsafe { String::from_utf8_unchecked(s.to_vec()) }
         })
         .collect();
-    result.sort();
+
+    result.par_sort();
     result
 }