add first benchmark

CONTRIBUTING.md

@@ -40,3 +40,20 @@ To run fuzzer:
 ```sh
 cargo +nightly fuzz run edit
 ```
+
+## Run benchmark
+
+Benchmarks are available using [Criterion.rs][criterion].
+
+To separate `criterion` crate dependency, benchmark suites are separated as another crate in [bench/](./bench).
+
+To run benchmarks:
+
+```sh
+cd ./bench
+cargo bench --benches
+```
+
+See [README in bench/](./bench/README.md) for more details.
+
+[criterion]: https://github.com/bheisler/criterion.rs

Cargo.toml

@@ -56,5 +56,13 @@ required-features = ["crossterm"]
 name = "variable"
 required-features = ["crossterm"]
 
+[workspace]
+members = [
+    "bench",
+]
+
+[profile.bench]
+lto = "thin"
+
 [package.metadata.docs.rs]
 all-features = true

bench/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "tui-textarea-bench"
+version = "0.0.0"
+edition = "2021"
+publish = false
+license = "MIT"
+
+[lib]
+bench = false
+
+[dependencies]
+tui-textarea = { path = "..", default-features = false }
+tui = { version = "0.18", default-features = false }
+
+[dev-dependencies]
+criterion = "0.3"
+
+[[bench]]
+name = "insert"
+harness = false

bench/README.md

@@ -0,0 +1,34 @@
+Benchmarks for tui-textarea using [Criterion.rs][criterion].
+
+To run all benchmarks:
+
+```sh
+cargo bench --benches
+```
+
+To run specific benchmark suite:
+
+```sh
+cargo bench --bench insert
+```
+
+To filter benchmarks:
+
+```sh
+cargo bench append::1_lorem
+```
+
+To compare benchmark results with [critcmp][]:
+
+```sh
+git checkout main
+cargo bench -- --save-baseline base
+
+git checkout your-feature
+cargo bench -- --save-baseline change
+
+critcmp base change
+```
+
+[criterion]: https://github.com/bheisler/criterion.rs
+[critcmp]: https://github.com/BurntSushi/critcmp

bench/benches/insert.rs

@@ -0,0 +1,57 @@
+use criterion::{black_box, criterion_group, criterion_main, Criterion};
+use tui_textarea::{Input, Key, TextArea};
+use tui_textarea_bench::dummy_terminal;
+
+const LOREM: &[&str] = &[
+    "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do",
+    "eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim",
+    "ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut",
+    "aliquip ex ea commodo consequat. Duis aute irure dolor in",
+    "reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla",
+    "pariatur. Excepteur sint occaecat cupidatat non proident, sunt in",
+    "culpa qui officia deserunt mollit anim id est laborum.",
+];
+
+#[inline]
+fn append_lorem(repeat: usize) -> usize {
+    let mut textarea = TextArea::default();
+    let mut term = dummy_terminal();
+    for _ in 0..repeat {
+        for line in LOREM {
+            for c in line.chars() {
+                textarea.input(Input {
+                    key: Key::Char(c),
+                    ctrl: false,
+                    alt: false,
+                });
+            }
+            term.draw(|f| {
+                f.render_widget(textarea.widget(), f.size());
+            })
+            .unwrap();
+        }
+        textarea.input(Input {
+            key: Key::Enter,
+            ctrl: false,
+            alt: false,
+        });
+        term.draw(|f| {
+            f.render_widget(textarea.widget(), f.size());
+        })
+        .unwrap();
+    }
+    textarea.lines().len()
+}
+
+fn append(c: &mut Criterion) {
+    c.bench_function("append::1_lorem", |b| b.iter(|| black_box(append_lorem(1))));
+    c.bench_function("append::10_lorem", |b| {
+        b.iter(|| black_box(append_lorem(10)))
+    });
+    c.bench_function("append::100_lorem", |b| {
+        b.iter(|| black_box(append_lorem(100)))
+    });
+}
+
+criterion_group!(insert, append);
+criterion_main!(insert);

bench/src/lib.rs

@@ -0,0 +1,71 @@
+// We use empty backend for our benchmark instead of tui::backend::TestBackend to make impact of benchmark from tui-rs
+// as small as possible.
+
+use std::io;
+use tui::backend::Backend;
+use tui::buffer::Cell;
+use tui::layout::Rect;
+use tui::Terminal;
+
+pub struct DummyBackend {
+    width: u16,
+    height: u16,
+    cursor: (u16, u16),
+}
+
+impl Default for DummyBackend {
+    fn default() -> Self {
+        Self {
+            width: 80,
+            height: 24,
+            cursor: (0, 0),
+        }
+    }
+}
+
+impl Backend for DummyBackend {
+    fn draw<'a, I>(&mut self, _content: I) -> Result<(), io::Error>
+    where
+        I: Iterator<Item = (u16, u16, &'a Cell)>,
+    {
+        Ok(())
+    }
+
+    fn hide_cursor(&mut self) -> Result<(), io::Error> {
+        Ok(())
+    }
+
+    fn show_cursor(&mut self) -> Result<(), io::Error> {
+        Ok(())
+    }
+
+    fn get_cursor(&mut self) -> Result<(u16, u16), io::Error> {
+        Ok(self.cursor)
+    }
+
+    fn set_cursor(&mut self, x: u16, y: u16) -> Result<(), io::Error> {
+        self.cursor = (x, y);
+        Ok(())
+    }
+
+    fn clear(&mut self) -> Result<(), io::Error> {
+        Ok(())
+    }
+
+    fn size(&self) -> Result<Rect, io::Error> {
+        Ok(Rect {
+            x: 0,
+            y: 0,
+            width: self.width,
+            height: self.height,
+        })
+    }
+
+    fn flush(&mut self) -> Result<(), io::Error> {
+        Ok(())
+    }
+}
+
+pub fn dummy_terminal() -> Terminal<DummyBackend> {
+    Terminal::new(DummyBackend::default()).unwrap()
+}