Add slow compose reproducer

Author: vlad-ivanov-name

Cargo.lock

@@ -9,6 +9,10 @@ keywords = ["git", "monorepo", "workflow", "scm"]
 readme = "../README.md"
 edition = "2024"
 
+[[bench]]
+name = "ultrawide"
+harness = false
+
 [dependencies]
 backtrace = "0.3.76"
 bitvec = "1.0.1"
@@ -37,5 +41,9 @@ sled = "0.34.7"
 tracing = { workspace = true }
 toml = { workspace = true }
 
+[dev-dependencies]
+rand = "0.9.2"
+criterion2 = { version = "3.0.2" }
+
 [features]
 incubating = []

josh-core/Cargo.toml

@@ -0,0 +1,65 @@
+use criterion::{Criterion, criterion_group, criterion_main};
+use itertools::Itertools;
+use rand::Rng;
+use rand::distr::{Alphabetic, Distribution};
+use rand::rngs::ThreadRng;
+use std::path::PathBuf;
+
+const N_PATHS: usize = 30;
+
+fn generate_paths() -> Vec<PathBuf> {
+    const PATH_COMPONENTS_MAX: usize = 10;
+    const PATH_COMPONENT_LEN: usize = 2;
+
+    // Create a single path component -- random lowercase characters,
+    // length of PATH_COMPONENT_LEN
+    fn make_path_component(rng: &mut ThreadRng) -> String {
+        (0..PATH_COMPONENT_LEN)
+            .map(|_| {
+                let ch = Alphabetic.sample(rng) as char;
+                ch.to_ascii_lowercase()
+            })
+            .collect()
+    }
+
+    // Create a single path -- anywhere from 1 to PATH_COMPONENTS_MAX components
+    fn make_path(rng: &mut ThreadRng) -> PathBuf {
+        let num_components = rng.random_range(1..=PATH_COMPONENTS_MAX);
+        let mut path = PathBuf::new();
+
+        for _ in 0..num_components {
+            path.push(make_path_component(rng))
+        }
+
+        path
+    }
+
+    let mut rng = rand::rng();
+
+    // Finally, create N_PATHS of random paths
+    (0..N_PATHS).map(|_| make_path(&mut rng)).collect()
+}
+
+fn ultrawide(c: &mut Criterion) {
+    c.bench_function("ultrawide_filter_parse", |b| {
+        b.iter_with_setup_wrapper(|runner| {
+            let filter = generate_paths()
+                .into_iter()
+                .map(|p| {
+                    let p = p.display().to_string();
+                    format!("::{p}/")
+                })
+                .join(",");
+
+            let filter = format!(":[{}]", filter);
+
+            runner.run(move || {
+                let filter = josh_core::filter::parse(&filter).expect("failed to parse");
+                std::hint::black_box(filter);
+            })
+        });
+    });
+}
+
+criterion_group!(benches, ultrawide);
+criterion_main!(benches);