Use handwritten ansi parser (#109)

This removes the heavy `regex` dependency from the ANSI feature.

Co-authored-by: Armin Ronacher <[email protected]>

.github/workflows/ci.yml

@@ -5,6 +5,34 @@ on:
   pull_request:
     branches: [master]
 jobs:
+  build-msrv:
+    name: Build on MSRV (1.40)
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - os: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+            rust: 1.40.0
+          - os: windows-latest
+            target: i686-pc-windows-msvc
+            rust: 1.40.0
+    runs-on: ${{ matrix.os }}
+    steps:
+      - name: Install rust
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: ${{ matrix.rust }}
+          target: ${{ matrix.target }}
+          override: true
+      - name: Checkout
+        uses: actions/checkout@v2
+      - name: Build
+        uses: actions-rs/cargo@v1
+        with:
+          command: check
+          args: --target ${{ matrix.target }}
   test:
     name: Tests
     strategy:
@@ -13,19 +41,19 @@ jobs:
         include:
           - os: macos-latest
             target: x86_64-apple-darwin
-            rust: 1.40.0
+            rust: 1.51.0
           - os: ubuntu-latest
             target: x86_64-unknown-linux-gnu
-            rust: 1.40.0
+            rust: 1.51.0
           - os: ubuntu-latest
             target: i686-unknown-linux-gnu
-            rust: 1.40.0
+            rust: 1.51.0
           - os: windows-latest
             target: i686-pc-windows-msvc
-            rust: 1.40.0
+            rust: 1.51.0
           - os: windows-latest
             target: x86_64-pc-windows-msvc
-            rust: 1.40.0
+            rust: 1.51.0
           - os: ubuntu-latest
             target: x86_64-unknown-linux-gnu
             rust: stable
@@ -70,7 +98,7 @@ jobs:
         uses: actions-rs/toolchain@v1
         with:
           profile: minimal
-          toolchain: 1.40.0
+          toolchain: 1.51.0
           target: ${{ matrix.target }}
           override: true
       - name: Checkout

Cargo.toml

@@ -13,8 +13,8 @@ readme = "README.md"
 
 [features]
 default = ["unicode-width", "ansi-parsing"]
-windows-console-colors = ["ansi-parsing", "winapi-util"]
-ansi-parsing = ["regex"]
+windows-console-colors = ["ansi-parsing", "regex", "winapi-util"]
+ansi-parsing = []
 
 [dependencies]
 once_cell = "1"
@@ -27,3 +27,12 @@ unicode-width = { version = "0.1", optional = true }
 winapi = { version = "0.3", features = ["winbase", "winuser", "consoleapi", "processenv", "wincon"] }
 winapi-util = { version = "0.1.3", optional = true }
 encode_unicode = "0.3"
+
+[dev-dependencies]
+criterion = "0.3.5"
+proptest = "1.0.0"
+regex = "1.4.2"
+
+[[bench]]
+name = "ansi_parser"
+harness = false

benches/ansi_parser.rs

@@ -0,0 +1,27 @@
+use console::{strip_ansi_codes, AnsiCodeIterator};
+use criterion::{black_box, criterion_group, criterion_main, Criterion, Throughput};
+
+use std::{fs, path::Path};
+
+pub fn parse_throughput(c: &mut Criterion) {
+    let session_log_path = Path::new("tests")
+        .join("data")
+        .join("sample_zellij_session.log");
+    let session_log = fs::read_to_string(session_log_path).unwrap();
+
+    let mut group = c.benchmark_group("ansi-parsing");
+    group.throughput(Throughput::Bytes(session_log.len() as u64));
+    group.bench_function("parse", |b| {
+        b.iter(|| {
+            let v: Vec<_> = AnsiCodeIterator::new(&session_log).collect();
+            black_box(v);
+        })
+    });
+    group.bench_function("strip", |b| {
+        b.iter(|| black_box(strip_ansi_codes(&session_log)))
+    });
+    group.finish();
+}
+
+criterion_group!(throughput, parse_throughput);
+criterion_main!(throughput);