Add a glob matcher

crates/edit/benches/lib.rs

@@ -10,9 +10,8 @@ use std::{mem, vec};
 use criterion::{BenchmarkId, Criterion, Throughput, criterion_group, criterion_main};
 use edit::helpers::*;
 use edit::simd::MemsetSafe;
-use edit::{buffer, hash, json, oklab, simd, unicode};
-use stdext::arena;
-use stdext::arena::{Arena, scratch_arena};
+use edit::{buffer, glob, hash, json, oklab, simd, unicode};
+use stdext::arena::{self, Arena, scratch_arena};
 
 struct EditingTracePatch<'a>(usize, usize, &'a str);
 
@@ -136,6 +135,15 @@ fn bench_buffer(c: &mut Criterion) {
         });
 }
 
+fn bench_glob(c: &mut Criterion) {
+    // Same benchmark as in glob-match
+    const PATH: &str = "foo/bar/foo/bar/foo/bar/foo/bar/foo/bar.txt";
+    const GLOB: &str = "foo/**/bar.txt";
+
+    c.benchmark_group("glob")
+        .bench_function("glob_match", |b| b.iter(|| assert!(glob::glob_match(GLOB, PATH))));
+}
+
 fn bench_hash(c: &mut Criterion) {
     c.benchmark_group("hash")
         .throughput(Throughput::Bytes(8))
@@ -275,6 +283,7 @@ fn bench(c: &mut Criterion) {
     arena::init(128 * MEBI).unwrap();
 
     bench_buffer(c);
+    bench_glob(c);
     bench_hash(c);
     bench_json(c);
     bench_oklab(c);

crates/edit/src/glob.rs

@@ -0,0 +1,273 @@
+// Copyright (c) Microsoft Corporation.
+// Licensed under the MIT License.
+
+//! Simple glob matching.
+//!
+//! Supported patterns:
+//! - `*` matches any characters except for path separators, including an empty string.
+//! - `**` matches any characters, including an empty string.
+//!   For convenience, `/**/` also matches `/`.
+
+use std::path::is_separator;
+
+#[inline]
+pub fn glob_match<P: AsRef<[u8]>, N: AsRef<[u8]>>(pattern: P, name: N) -> bool {
+    glob(pattern.as_ref(), name.as_ref())
+}
+
+fn glob(pattern: &[u8], name: &[u8]) -> bool {
+    fast_path(pattern, name).unwrap_or_else(|| slow_path(pattern, name))
+}
+
+// Fast-pass for the most common patterns:
+// * Matching files by extension (e.g., **/*.rs)
+// * Matching files by name (e.g., **/Cargo.toml)
+fn fast_path(pattern: &[u8], name: &[u8]) -> Option<bool> {
+    // In either case, the glob must start with "**/".
+    let mut suffix = pattern.strip_prefix(b"**/")?;
+    if suffix.is_empty() {
+        return None;
+    }
+
+    // Determine whether it's "**/" or "**/*".
+    let mut needs_dir_anchor = true;
+    if let Some(s) = suffix.strip_prefix(b"*") {
+        suffix = s;
+        needs_dir_anchor = false;
+    }
+
+    // Restrict down to anything we can handle with a suffix check.
+    if suffix.is_empty() || contains_magic(suffix) {
+        return None;
+    }
+
+    Some(
+        match_path_suffix(name, suffix)
+            && (
+                // In case of "**/*extension" a simple suffix match is sufficient.
+                !needs_dir_anchor
+                // But for "**/filename" we need to ensure that path is either "filename"...
+                || name.len() == suffix.len()
+                // ...or that it is ".../filename".
+                || is_separator(name[name.len() - suffix.len() - 1] as char)
+            ),
+    )
+}
+
+fn contains_magic(pattern: &[u8]) -> bool {
+    pattern.contains(&b'*')
+}
+
+fn match_path_suffix(path: &[u8], suffix: &[u8]) -> bool {
+    if path.len() < suffix.len() {
+        return false;
+    }
+
+    let path = &path[path.len() - suffix.len()..];
+
+    #[cfg(windows)]
+    {
+        path.iter().zip(suffix.iter()).all(|(a, b)| {
+            let a = if *a == b'\\' { b'/' } else { *a };
+            let b = if *b == b'\\' { b'/' } else { *b };
+            a.eq_ignore_ascii_case(&b)
+        })
+    }
+
+    #[cfg(not(windows))]
+    path.eq_ignore_ascii_case(suffix)
+}
+
+// This code is based on https://research.swtch.com/glob.go
+// It's not particularly fast, but it doesn't need to be. It doesn't run often.
+#[cold]
+fn slow_path(pattern: &[u8], name: &[u8]) -> bool {
+    let mut px = 0;
+    let mut nx = 0;
+    let mut next_px = 0;
+    let mut next_nx = 0;
+    let mut is_double_star = false;
+
+    while px < pattern.len() || nx < name.len() {
+        if px < pattern.len() {
+            match pattern[px] {
+                b'*' => {
+                    // Try to match at nx. If that doesn't work out, restart at nx+1 next.
+                    next_px = px;
+                    next_nx = nx + 1;
+                    px += 1;
+                    is_double_star = false;
+
+                    if px < pattern.len() && pattern[px] == b'*' {
+                        px += 1;
+                        is_double_star = true;
+
+                        // For convenience, /**/ also matches /
+                        if px >= 3
+                            && px < pattern.len()
+                            && pattern[px] == b'/'
+                            && pattern[px - 3] == b'/'
+                        {
+                            px += 1;
+                        }
+                    }
+                    continue;
+                }
+                c => {
+                    if nx < name.len() && name[nx].eq_ignore_ascii_case(&c) {
+                        px += 1;
+                        nx += 1;
+                        continue;
+                    }
+                }
+            }
+        }
+
+        // Mismatch. Maybe restart.
+        if next_nx > 0
+            && next_nx <= name.len()
+            && (is_double_star || !is_separator(name[next_nx - 1] as char))
+        {
+            px = next_px;
+            nx = next_nx;
+            continue;
+        }
+
+        return false;
+    }
+
+    true
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_glob_match() {
+        let tests = [
+            // Test cases from https://research.swtch.com/glob.go
+            ("", "", true),
+            ("x", "", false),
+            ("", "x", false),
+            ("abc", "abc", true),
+            ("*", "abc", true),
+            ("*c", "abc", true),
+            ("*b", "abc", false),
+            ("a*", "abc", true),
+            ("b*", "abc", false),
+            ("a*", "a", true),
+            ("*a", "a", true),
+            ("a*b*c*d*e*", "axbxcxdxe", true),
+            ("a*b*c*d*e*", "axbxcxdxexxx", true),
+            ("*x", "xxx", true),
+            // Test cases from https://github.com/golang/go/blob/master/src/path/filepath/match_test.go
+            ("a*", "ab/c", false),
+            ("a*b", "a/b", false),
+            ("a*/b", "abc/b", true),
+            ("a*/b", "a/c/b", false),
+            ("a*b*c*d*e*/f", "axbxcxdxe/f", true),
+            ("a*b*c*d*e*/f", "axbxcxdxexxx/f", true),
+            ("a*b*c*d*e*/f", "axbxcxdxe/xxx/f", false),
+            ("a*b*c*d*e*/f", "axbxcxdxexxx/fff", false),
+            // Single star (*)
+            // - Empty string
+            ("*", "", true),
+            // - Anything else is covered above
+            // Double star (**)
+            // - Empty string
+            ("**", "", true),
+            ("a**", "a", true),
+            ("**a", "a", true),
+            // - Prefix
+            ("**", "abc", true),
+            ("**", "foo/baz/bar", true),
+            ("**c", "abc", true),
+            ("**b", "abc", false),
+            // - Infix
+            ("a**c", "ac", true),
+            ("a**c", "abc", true),
+            ("a**c", "abd", false),
+            ("a**d", "abc", false),
+            ("a**c", "a/bc", true),
+            ("a**c", "ab/c", true),
+            ("a**c", "a/b/c", true),
+            // -- Infix with left separator
+            ("a/**c", "ac", false),
+            ("a/**c", "a/c", true),
+            ("a/**c", "b/c", false),
+            ("a/**c", "a/d", false),
+            ("a/**c", "a/b/c", true),
+            ("a/**c", "a/b/d", false),
+            ("a/**c", "d/b/c", false),
+            // -- Infix with right separator
+            ("a**/c", "ac", false),
+            ("a**/c", "a/c", true),
+            ("a**/c", "b/c", false),
+            ("a**/c", "a/d", false),
+            ("a**/c", "a/b/c", true),
+            ("a**/c", "a/b/d", false),
+            ("a**/c", "d/b/c", false),
+            // - Infix with two separators
+            ("a/**/c", "ac", false),
+            ("a/**/c", "a/c", true),
+            ("a/**/c", "b/c", false),
+            ("a/**/c", "a/d", false),
+            ("a/**/c", "a/b/c", true),
+            ("a/**/c", "a/b/d", false),
+            ("a/**/c", "d/b/c", false),
+            // - * + * is covered above
+            // - * + **
+            ("a*b**c", "abc", true),
+            ("a*b**c", "aXbYc", true),
+            ("a*b**c", "aXb/Yc", true),
+            ("a*b**c", "aXbY/Yc", true),
+            ("a*b**c", "aXb/Y/c", true),
+            ("a*b**c", "a/XbYc", false),
+            ("a*b**c", "aX/XbYc", false),
+            ("a*b**c", "a/X/bYc", false),
+            // - ** + *
+            ("a**b*c", "abc", true),
+            ("a**b*c", "aXbYc", true),
+            ("a**b*c", "aXb/Yc", false),
+            ("a**b*c", "aXbY/Yc", false),
+            ("a**b*c", "aXb/Y/c", false),
+            ("a**b*c", "a/XbYc", true),
+            ("a**b*c", "aX/XbYc", true),
+            ("a**b*c", "a/X/bYc", true),
+            // - ** + **
+            ("a**b**c", "abc", true),
+            ("a**b**c", "aXbYc", true),
+            ("a**b**c", "aXb/Yc", true),
+            ("a**b**c", "aXbY/Yc", true),
+            ("a**b**c", "aXb/Y/c", true),
+            ("a**b**c", "aXbYc", true),
+            ("a**b**c", "a/XbYc", true),
+            ("a**b**c", "aX/XbYc", true),
+            ("a**b**c", "a/X/bYc", true),
+            // Case insensitivity
+            ("*.txt", "file.TXT", true),
+            ("**/*.rs", "dir/file.RS", true),
+            // Optimized patterns: **/*.ext and **/name
+            ("**/*.rs", "foo.rs", true),
+            ("**/*.rs", "dir/foo.rs", true),
+            ("**/*.rs", "dir/sub/foo.rs", true),
+            ("**/*.rs", "foo.txt", false),
+            ("**/*.rs", "dir/foo.txt", false),
+            ("**/Cargo.toml", "Cargo.toml", true),
+            ("**/Cargo.toml", "dir/Cargo.toml", true),
+            ("**/Cargo.toml", "dir/sub/Cargo.toml", true),
+            ("**/Cargo.toml", "Cargo.lock", false),
+            ("**/Cargo.toml", "dir/Cargo.lock", false),
+        ];
+
+        for (pattern, name, expected) in tests {
+            let result = glob_match(pattern, name);
+            assert_eq!(
+                result, expected,
+                "test case ({:?}, {:?}, {}) failed, got {}",
+                pattern, name, expected, result
+            );
+        }
+    }
+}

crates/edit/src/lib.rs

@@ -25,6 +25,7 @@ pub mod clipboard;
 pub mod document;
 pub mod framebuffer;
 pub mod fuzzy;
+pub mod glob;
 pub mod hash;
 pub mod helpers;
 pub mod icu;