Use vendored tree-sitter-rust

Cargo.lock

@@ -96,6 +96,7 @@ name = "difftastic"
 version = "0.7.0"
 dependencies = [
  "atty",
+ "cc",
  "clap",
  "colored",
  "diff",
@@ -109,7 +110,6 @@ dependencies = [
  "term_size",
  "toml",
  "tree-sitter",
- "tree-sitter-rust",
  "typed-arena",
 ]
 
@@ -326,16 +326,6 @@ dependencies = [
  "regex",
 ]
 
-[[package]]
-name = "tree-sitter-rust"
-version = "0.19.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "784f7ef9cdbd4c895dc2d4bb785e95b4a5364a602eec803681db83d1927ddf15"
-dependencies = [
- "cc",
- "tree-sitter",
-]
-
 [[package]]
 name = "typed-arena"
 version = "2.0.1"

Cargo.toml

@@ -23,7 +23,9 @@ strsim = "0.10.0"
 lazy_static = "1.4.0"
 atty = "0.2.14"
 tree-sitter = "0.19.5"
-tree-sitter-rust = "0.19.0"
 
 [dev-dependencies]
 pretty_assertions = "0.6.1"
+
+[build-dependencies]
+cc="*"

build.rs

@@ -0,0 +1,12 @@
+use std::path::PathBuf;
+
+fn main() {
+    let dir: PathBuf = ["vendor", "tree-sitter-rust", "src"].iter().collect();
+
+    cc::Build::new()
+        .include(&dir)
+        .file(dir.join("parser.c"))
+        .file(dir.join("scanner.c"))
+        .warnings(false) // ignore unused parameter warnings
+        .compile("tree-sitter-javascript");
+}

src/sitter.rs

@@ -1,19 +1,25 @@
 use std::ffi::OsStr;
 
-use tree_sitter::{Parser, TreeCursor};
+use tree_sitter::{Language, Parser, TreeCursor};
 use typed_arena::Arena;
 
 use crate::{lines::NewlinePositions, syntax::Syntax};
 
+extern "C" {
+    fn tree_sitter_rust() -> Language;
+}
+
 pub fn supported(extension: &OsStr) -> bool {
     extension == "rs"
 }
 
 pub fn parse<'a>(arena: &'a Arena<Syntax<'a>>, src: &str) -> Vec<&'a Syntax<'a>> {
     let mut parser = Parser::new();
+    let language = unsafe { tree_sitter_rust() };
     parser
-        .set_language(tree_sitter_rust::language())
-        .expect("Error loading Rust grammar");
+        .set_language(language)
+        .expect("Incompatible tree-sitter version in tree-sitter-rust");
+
     let tree = parser.parse(src, None).unwrap();
 
     let nl_pos = NewlinePositions::from(src);