Merge pull request #2405 from cruessler/benchmark-line-stats

Add benchmark for counting additions/removals in diff

Author: Byron

Cargo.lock

@@ -39,6 +39,11 @@ wasm = ["dep:getrandom"]
 [lib]
 doctest = false
 
+[[bench]]
+name = "line-count"
+harness = false
+path = "./benches/line_count.rs"
+
 [dependencies]
 gix-index = { version = "^0.46.0", path = "../gix-index", optional = true }
 gix-pathspec = { version = "^0.15.0", path = "../gix-pathspec", optional = true }
@@ -63,6 +68,10 @@ bstr = { version = "1.12.0", default-features = false }
 
 document-features = { version = "0.2.0", optional = true }
 
+[dev-dependencies]
+criterion = "0.8.0"
+imara-diff-v2 = { version = "0.2.0", package = "imara-diff" }
+
 [package.metadata.docs.rs]
 all-features = true
 features = ["document-features"]

gix-diff/Cargo.toml

@@ -0,0 +1,118 @@
+use criterion::{criterion_group, criterion_main, Criterion};
+
+struct BenchmarkTokenSource {
+    number_of_lines: u32,
+    skip_every: u32,
+}
+
+impl BenchmarkTokenSource {
+    fn new(number_of_lines: u32, skip_every: u32) -> Self {
+        Self {
+            number_of_lines,
+            skip_every,
+        }
+    }
+}
+
+struct BenchmarkTokenizer {
+    number_of_lines: u32,
+    skip_every: u32,
+    current: u32,
+}
+
+impl BenchmarkTokenizer {
+    fn new(number_of_lines: u32, skip_every: u32) -> Self {
+        Self {
+            number_of_lines,
+            skip_every,
+            current: 0,
+        }
+    }
+}
+
+impl Iterator for BenchmarkTokenizer {
+    type Item = String;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        if self.current < self.number_of_lines {
+            let item = self.current.to_string();
+
+            self.current += 1;
+
+            if self.current % self.skip_every == 0 {
+                self.current += 1;
+            }
+
+            Some(item)
+        } else {
+            None
+        }
+    }
+}
+
+impl imara_diff::intern::TokenSource for BenchmarkTokenSource {
+    type Token = String;
+
+    type Tokenizer = BenchmarkTokenizer;
+
+    fn tokenize(&self) -> Self::Tokenizer {
+        BenchmarkTokenizer::new(self.number_of_lines, self.skip_every)
+    }
+
+    fn estimate_tokens(&self) -> u32 {
+        self.number_of_lines
+    }
+}
+
+impl imara_diff_v2::TokenSource for BenchmarkTokenSource {
+    type Token = String;
+
+    type Tokenizer = BenchmarkTokenizer;
+
+    fn tokenize(&self) -> Self::Tokenizer {
+        BenchmarkTokenizer::new(self.number_of_lines, self.skip_every)
+    }
+
+    fn estimate_tokens(&self) -> u32 {
+        self.number_of_lines
+    }
+}
+
+fn count_lines(c: &mut Criterion) {
+    let input = imara_diff::intern::InternedInput::new(
+        BenchmarkTokenSource::new(10_000, 5),
+        BenchmarkTokenSource::new(10_000, 6),
+    );
+
+    let input_v2 = imara_diff_v2::InternedInput::new(
+        BenchmarkTokenSource::new(10_000, 5),
+        BenchmarkTokenSource::new(10_000, 6),
+    );
+
+    c.bench_function("imara-diff 0.1", |b| {
+        b.iter(|| {
+            let counters = gix_diff::blob::diff(
+                gix_diff::blob::Algorithm::Histogram,
+                &input,
+                gix_diff::blob::sink::Counter::default(),
+            );
+
+            assert_eq!(counters.insertions, 1666);
+            assert_eq!(counters.removals, 1333);
+        });
+    });
+    c.bench_function("imara-diff 0.2", |b| {
+        b.iter(|| {
+            let diff = imara_diff_v2::Diff::compute(imara_diff_v2::Algorithm::Histogram, &input_v2);
+
+            let additions = diff.count_additions();
+            let removals = diff.count_removals();
+
+            assert_eq!(additions, 1666);
+            assert_eq!(removals, 1333);
+        });
+    });
+}
+
+criterion_group!(benches, count_lines);
+criterion_main!(benches);