Initial attempt at adding support for pcre

Cargo.toml

@@ -38,14 +38,16 @@ ignore = "0.4.25"
 regex = "1.12.2"
 regex-syntax = "0.8"
 ctrlc = "3.5"
-globset = "0.4"
+globset = "0.4.18"
 anyhow = "1.0"
 etcetera = "0.11"
 normpath = "1.5.1"
 crossbeam-channel = "0.5.15"
 clap_complete = {version = "4.6.5", optional = true}
 faccess = "0.2.4"
 jiff = "0.2.27"
+memchr = "2.8.0"
+pcre2 = {version = "0.2.11", optional = true}
 
 [dependencies.clap]
 version = "4.6.1"
@@ -95,6 +97,7 @@ codegen-units = 1
 use-jemalloc = ["tikv-jemallocator"]
 completions = ["clap_complete"]
 base = ["use-jemalloc"]
+pcre = ["dep:pcre2"]
 default = ["use-jemalloc", "completions"]
 
 [package.metadata.binstall]

src/cli.rs

@@ -171,6 +171,18 @@ pub struct Opts {
     )]
     pub regex: bool,
 
+    /// Use the PCRE regex engine
+    ///
+    /// This allows you to use features like backreferences and lookarounds.
+    #[cfg(feature = "pcre")]
+    #[arg(
+        long,
+        overrides_with_all(["glob", "regex"]),
+        conflicts_with("fixed_strings"),
+        long_help
+    )]
+    pub pcre: bool,
+
     /// Treat the pattern as a literal string instead of a regular expression. Note
     /// that this also performs substring comparison. If you want to match on an
     /// exact filename, consider using '--glob' or '--exact' instead.
@@ -629,13 +641,11 @@ pub struct Opts {
     /// is considered a match. If your pattern starts with a dash (-), make sure to
     /// pass '--' first, or it will be considered as a flag (fd -- '-foo').
     #[arg(
-        default_value = "",
-        hide_default_value = true,
         value_name = "pattern",
         help = "the search pattern (a regular expression, unless '--glob' is used; optional)",
         long_help
     )]
-    pub pattern: String,
+    pub pattern: Option<String>,
 
     /// Set the path separator to use when printing file paths. The default is
     /// the OS-specific separator ('/' on Unix, '\' on Windows).

src/config.rs

@@ -12,9 +12,6 @@ use crate::fmt::FormatTemplate;
 
 /// Configuration options for *fd*.
 pub struct Config {
-    /// Whether the search is case-sensitive or case-insensitive.
-    pub case_sensitive: bool,
-
     /// Cached current working directory for absolute path construction.
     /// Populated when `--full-path` is set; `None` means search by filename only.
     pub full_path_base: Option<PathBuf>,

src/filesystem.rs

@@ -1,6 +1,4 @@
-use std::borrow::Cow;
 use std::env;
-use std::ffi::OsStr;
 use std::fs;
 use std::io;
 #[cfg(any(unix, target_os = "redox"))]
@@ -99,22 +97,6 @@ pub fn is_pipe(_: fs::FileType) -> bool {
     false
 }
 
-#[cfg(any(unix, target_os = "redox"))]
-pub fn osstr_to_bytes(input: &OsStr) -> Cow<'_, [u8]> {
-    use std::os::unix::ffi::OsStrExt;
-    Cow::Borrowed(input.as_bytes())
-}
-
-#[cfg(windows)]
-pub fn osstr_to_bytes(input: &OsStr) -> Cow<'_, [u8]> {
-    let string = input.to_string_lossy();
-
-    match string {
-        Cow::Owned(string) => Cow::Owned(string.into_bytes()),
-        Cow::Borrowed(string) => Cow::Borrowed(string.as_bytes()),
-    }
-}
-
 /// Remove the `./` prefix from a path.
 pub fn strip_current_dir(path: &Path) -> &Path {
     path.strip_prefix(".").unwrap_or(path)