fn resume()

in src/api/sync.rs [928:1005]

• 66 lines of code
• 1 McCabe index (conditional complexity)

    fn resume() {
        let tmp = TempDir::new();
        let api = ApiBuilder::new()
            .with_progress(false)
            .with_cache_dir(tmp.path.clone())
            .build()
            .unwrap();

        let model_id = "julien-c/dummy-unknown".to_string();
        let downloaded_path = api.model(model_id.clone()).download("config.json").unwrap();
        assert!(downloaded_path.exists());
        let val = Sha256::digest(std::fs::read(&*downloaded_path).unwrap());
        assert_eq!(
            val[..],
            hex!("b908f2b7227d4d31a2105dfa31095e28d304f9bc938bfaaa57ee2cacf1f62d32")
        );

        let blob = std::fs::canonicalize(&downloaded_path).unwrap();
        let file = std::fs::OpenOptions::new().write(true).open(&blob).unwrap();
        let size = file.metadata().unwrap().len();
        let truncate: f32 = rand::random();
        let new_size = (size as f32 * truncate) as u64;
        file.set_len(new_size).unwrap();
        let mut blob_part = blob.clone();
        blob_part.set_extension("part");
        std::fs::rename(blob, &blob_part).unwrap();
        std::fs::remove_file(&downloaded_path).unwrap();
        let content = std::fs::read(&*blob_part).unwrap();
        assert_eq!(content.len() as u64, new_size);
        let val = Sha256::digest(content);
        // We modified the sha.
        assert!(
            val[..] != hex!("b908f2b7227d4d31a2105dfa31095e28d304f9bc938bfaaa57ee2cacf1f62d32")
        );
        let new_downloaded_path = api.model(model_id.clone()).download("config.json").unwrap();
        let val = Sha256::digest(std::fs::read(&*new_downloaded_path).unwrap());
        assert_eq!(downloaded_path, new_downloaded_path);
        assert_eq!(
            val[..],
            hex!("b908f2b7227d4d31a2105dfa31095e28d304f9bc938bfaaa57ee2cacf1f62d32")
        );

        // Here we prove the previous part was correctly resuming by purposefully corrupting the
        // file.
        let blob = std::fs::canonicalize(&downloaded_path).unwrap();
        let mut file = std::fs::OpenOptions::new().write(true).open(&blob).unwrap();
        let size = file.metadata().unwrap().len();
        // Not random for consistent sha corruption
        let truncate: f32 = 0.5;
        let new_size = (size as f32 * truncate) as u64;
        // Truncating
        file.set_len(new_size).unwrap();
        // Corrupting by changing a single byte.
        file.seek(SeekFrom::Start(new_size - 1)).unwrap();
        file.write_all(&[0]).unwrap();

        let mut blob_part = blob.clone();
        blob_part.set_extension("part");
        std::fs::rename(blob, &blob_part).unwrap();
        std::fs::remove_file(&downloaded_path).unwrap();
        let content = std::fs::read(&*blob_part).unwrap();
        assert_eq!(content.len() as u64, new_size);
        let val = Sha256::digest(content);
        // We modified the sha.
        assert!(
            val[..] != hex!("b908f2b7227d4d31a2105dfa31095e28d304f9bc938bfaaa57ee2cacf1f62d32")
        );
        let new_downloaded_path = api.model(model_id.clone()).download("config.json").unwrap();
        let val = Sha256::digest(std::fs::read(&*new_downloaded_path).unwrap());
        assert_eq!(downloaded_path, new_downloaded_path);
        println!("{new_downloaded_path:?}");
        println!("Corrupted {val:#x}");
        assert_eq!(
            val[..],
            // Corrupted sha
            hex!("32b83c94ee55a8d43d68b03a859975f6789d647342ddeb2326fcd5e0127035b5")
        );
    }