cull a bunch of vendor dependency files

Author: Qix-

.gitignore

@@ -1,3 +1,27 @@
 /target/
 /vendor/.vendor*/
 /vendor/**/*._oro-prepatch
+
+# Vendor-specific ignores
+/vendor/*/tests/*
+/vendor/*/examples/*
+/vendor/*/benches/*
+/vendor/**/.editorconfig
+/vendor/**/.github/*
+/vendor/**/release-plz.toml
+/vendor/**/rust-toolchain.toml
+
+!/vendor/**/.github/FUNDING.yml
+!/vendor/**/.github/FUNDING.yaml
+
+!/vendor/clap/examples/demo.rs
+!/vendor/clap/examples/demo.md
+!/vendor/winnow/examples/css
+/vendor/winnow/examples/css/*
+!/vendor/winnow/examples/css/parser.rs
+
+/vendor/flickzeug/test-data/
+vendor/flickzeug/src/patch/snapshots/
+
+# Building on windows isn't supported to begin with.
+/vendor/windows-sys/src/*

utils/build/src/cmd/vendor.rs

@@ -43,6 +43,28 @@ fn vendor() {
 	eprintln!("wrote .cargo/config.toml paths");
 
 	super::patch::apply_all();
+
+	eprintln!("cleaning vendor directory...");
+	match std::process::Command::new("git")
+		.arg("clean")
+		.arg("-dffX")
+		.arg("vendor")
+		.current_dir(vfs.root())
+		.stdout(std::process::Stdio::inherit())
+		.stderr(std::process::Stdio::inherit())
+		.stdin(std::process::Stdio::inherit())
+		.status()
+	{
+		Ok(status) if status.success() => {
+			eprintln!("cleaned vendor/ directory");
+		}
+		Ok(status) => {
+			panic!("git exited non-zero; is it installed?: {status}");
+		}
+		Err(err) => {
+			panic!("failed to spawn git to clean vendor/directory: {err}");
+		}
+	}
 }
 
 fn check() {