snapshot test

tests/snapshot.rs

@@ -0,0 +1,19 @@
+use democutter::cut;
+use expect_test::{expect_file, ExpectFile};
+use std::fs;
+
+fn snapshot(path: &str, expect: ExpectFile) {
+    let file = fs::read(path).unwrap();
+    let output = cut(&file, 30000, 50000);
+    let output_md5 = md5::compute(&output);
+
+    expect.assert_eq(&format!("{:x}", output_md5));
+}
+
+#[test]
+fn snapshot_gully() {
+    snapshot(
+        "test_data/gully.dem",
+        expect_file!["../test_data/gully_cut.md5"],
+    );
+}