Compute colors in parallel

CHANGELOG.md

@@ -19,6 +19,7 @@
 - No leading `./` prefix for non-interactive results, see above.
 - fd can now avoid `stat` syscalls even when colorizing paths, as long as the color scheme doesn't
   require metadata, see #1148 (@tavianator)
+- fd now colorizes paths in parallel, significantly improving performance, see #1148 (@tavianator)
 
 ## Other
 

src/config.rs

@@ -120,3 +120,10 @@ pub struct Config {
     /// Whether or not to strip the './' prefix for search results
     pub strip_cwd_prefix: bool,
 }
+
+impl Config {
+    /// Check whether results are being printed.
+    pub fn is_printing(&self) -> bool {
+        self.command.is_none()
+    }
+}

src/dir_entry.rs

@@ -2,7 +2,8 @@ use std::ffi::OsString;
 use std::fs::{FileType, Metadata};
 use std::path::{Path, PathBuf};
 
-use lscolors::Colorable;
+use lscolors::{Colorable, LsColors, Style};
+
 use once_cell::unsync::OnceCell;
 
 use crate::config::Config;
@@ -16,6 +17,7 @@ enum DirEntryInner {
 pub struct DirEntry {
     inner: DirEntryInner,
     metadata: OnceCell<Option<Metadata>>,
+    style: OnceCell<Option<Style>>,
 }
 
 impl DirEntry {
@@ -24,6 +26,7 @@ impl DirEntry {
         Self {
             inner: DirEntryInner::Normal(e),
             metadata: OnceCell::new(),
+            style: OnceCell::new(),
         }
     }
 
@@ -31,6 +34,7 @@ impl DirEntry {
         Self {
             inner: DirEntryInner::BrokenSymlink(path),
             metadata: OnceCell::new(),
+            style: OnceCell::new(),
         }
     }
 
@@ -88,6 +92,12 @@ impl DirEntry {
             DirEntryInner::BrokenSymlink(_) => None,
         }
     }
+
+    pub fn style(&self, ls_colors: &LsColors) -> Option<&Style> {
+        self.style
+            .get_or_init(|| ls_colors.style_for(self).cloned())
+            .as_ref()
+    }
 }
 
 impl PartialEq for DirEntry {

src/output.rs

@@ -90,8 +90,8 @@ fn print_entry_colorized<W: Write>(
         write!(stdout, "{}", style.paint(parent_str))?;
     }
 
-    let style = ls_colors
-        .style_for(entry)
+    let style = entry
+        .style(ls_colors)
         .map(Style::to_ansi_term_style)
         .unwrap_or_default();
     write!(stdout, "{}", style.paint(&path_str[offset..]))?;

src/walk.rs

@@ -535,6 +535,13 @@ fn spawn_senders(
                 }
             }
 
+            if config.is_printing() {
+                if let Some(ls_colors) = &config.ls_colors {
+                    // Try to compute colors in parallel
+                    entry.style(ls_colors);
+                }
+            }
+
             let send_result = tx_thread.send(WorkerResult::Entry(entry));
 
             if send_result.is_err() {