test(block): Added benchmarks

Added benchmarks to the block widget to uncover eventual performance issues

ratatui#137

Cargo.toml

@@ -61,6 +61,11 @@ rand = "0.8"
 name = "paragraph"
 harness = false
 
+[[bench]]
+name = "block"
+harness = false
+
+
 [[example]]
 name = "barchart"
 required-features = ["crossterm"]

benches/block.rs

@@ -0,0 +1,70 @@
+use criterion::{black_box, criterion_group, criterion_main, Bencher, BenchmarkId, Criterion};
+use ratatui::{
+    buffer::Buffer,
+    layout::Rect,
+    widgets::{Block, Borders, Padding, Widget},
+};
+
+/// Benchmark for rendering a block.
+pub fn block(c: &mut Criterion) {
+    let mut group = c.benchmark_group("block");
+
+    // Benchmark that measures the overhead of creating a block separately from rendering
+    group.bench_function("new", |b| b.iter(|| black_box(Block::new())));
+
+    for buffer_size in &[
+        Rect::new(0, 0, 20, 10),  // square-ish
+        Rect::new(0, 0, 100, 50), // vertically split screen
+        Rect::new(0, 0, 200, 50), // 1080p fullscreen with medium font
+    ] {
+        let buffer_size_displayable = &format!("{}x{}", buffer_size.width, buffer_size.height);
+
+        // Render an empty block
+        group.bench_with_input(
+            BenchmarkId::new("render_empty", buffer_size_displayable),
+            &Block::new(),
+            |b, block| render(b, block, buffer_size),
+        );
+
+        // Render with default borders
+        group.bench_with_input(
+            BenchmarkId::new("render_default_borders", buffer_size_displayable),
+            &Block::new().borders(Borders::ALL),
+            |b, block| render(b, block, buffer_size),
+        );
+
+        // Render with one default title
+        group.bench_with_input(
+            BenchmarkId::new("render_default_title", buffer_size_displayable),
+            &Block::new().title("default title"),
+            |b, block| render(b, block, buffer_size),
+        );
+
+        // Render with padding
+        group.bench_with_input(
+            BenchmarkId::new("render_padding", buffer_size_displayable),
+            &Block::new().padding(Padding::new(5, 5, 2, 2)),
+            |b, block| render(b, block, buffer_size),
+        );
+
+        // Calculate inner area
+        group.bench_with_input(
+            BenchmarkId::new("compute_inner_area", buffer_size_displayable),
+            &Block::new(),
+            |b, block| b.iter(|| block.inner(*buffer_size)),
+        );
+    }
+
+    group.finish();
+}
+
+/// render the block into a buffer of the given `size`
+fn render(bencher: &mut Bencher, block: &Block, size: &Rect) {
+    let mut buffer = Buffer::empty(*size);
+    bencher.iter(|| {
+        block.clone().render(buffer.area, &mut buffer);
+    })
+}
+
+criterion_group!(benches, block);
+criterion_main!(benches);