fif/src/tests/mod.rs

use crate::findings::Findings;
use crate::formats::{Format, Shell};
use crate::inspectors::{mime_extension_lookup, BUF_SIZE};
use crate::mime_db::MimeDb;
use crate::string_type::String;
use crate::{extension_from_path, scan_directory, scan_from_walkdir};

use mime_guess::mime::{APPLICATION_OCTET_STREAM, APPLICATION_PDF, IMAGE_JPEG, IMAGE_PNG};
use mime_guess::Mime;

use std::collections::HashMap;
use std::ffi::OsStr;
use std::path::Path;

const JPEG_BYTES: &[u8] = b"\xFF\xD8\xFF";
const PNG_BYTES: &[u8] = b"\x89\x50\x4E\x47\x0D\x0A\x1A\x0A";
const PDF_BYTES: &[u8] = b"%PDF-";
const ZIP_BYTES: &[u8] = b"PK\x03\x04";

cfg_if::cfg_if! {
	if #[cfg(any(all(unix, feature = "infer-backend"), all(not(unix), not(feature = "xdg-mime-backend"))))] {
		fn get_mime_db() -> crate::mime_db::InferDb {
			crate::mime_db::InferDb::init()
		}
	} else {
		fn get_mime_db() -> crate::mime_db::XdgDb {
			crate::mime_db::XdgDb::init()
		}
	}
}

fn application_zip() -> Mime {
	use std::str::FromStr;
	Mime::from_str("application/zip").unwrap()
}

#[test]
/// Ensure that `extension_from_path` successfully returns the extension from a set of paths.
fn get_ext() {
	let mut ext_checks: HashMap<_, Option<&OsStr>> = HashMap::new();
	ext_checks.insert(Path::new("test.txt"), Some(OsStr::new("txt")));
	ext_checks.insert(Path::new("test.zip"), Some(OsStr::new("zip")));
	ext_checks.insert(Path::new("test.tar.gz"), Some(OsStr::new("gz")));
	ext_checks.insert(Path::new("test."), Some(OsStr::new("")));
	ext_checks.insert(Path::new("test"), None);
	ext_checks.insert(Path::new(".hidden"), None);

	for (path, ext) in ext_checks {
		assert_eq!(extension_from_path(path), ext)
	}
}

#[test]
/// Ensure that the mime types for JPEG, PNG, PDF, and ZIP are detected from their magic numbers.
fn detect_type() {
	let db = get_mime_db();
	assert_eq!(db.get_type(JPEG_BYTES), Some(IMAGE_JPEG));
	assert_eq!(db.get_type(PNG_BYTES), Some(IMAGE_PNG));
	assert_eq!(db.get_type(PDF_BYTES), Some(APPLICATION_PDF));
	assert_eq!(db.get_type(ZIP_BYTES), Some(application_zip()));
}

#[test]
/// Ensure that `mime_extension_lookup` works as expected, and that the set of extensions for JPEG, PNG, PDF, and ZIP
/// contain "jpg", "png", "pdf", and "zip", respectively.
fn recommend_ext() {
	assert!(mime_extension_lookup(IMAGE_JPEG)
		.unwrap()
		.contains(&String::from("jpg")));
	assert!(mime_extension_lookup(IMAGE_PNG).unwrap().contains(&String::from("png")));
	assert!(mime_extension_lookup(APPLICATION_PDF)
		.unwrap()
		.contains(&String::from("pdf")));
	assert!(mime_extension_lookup(application_zip())
		.unwrap()
		.contains(&String::from("zip")));
}

#[test]
/// Create a simple directory with some files, run `scan_directory` on it, and ensure that the files have their
/// associated mime types correctly deduced.
fn simple_directory() {
	use crate::parameters::ScanOpts;
	use std::borrow::Borrow;
	use std::fs::File;
	use std::io::Write;
	use tempfile::tempdir;

	// set of files to scan. all but the last files have magic numbers corresponding to their extension, except for
	// "wrong.jpg", which is actually a png.
	let mut files = HashMap::new();
	files.insert("test.jpg", JPEG_BYTES);
	files.insert("test.jpeg", JPEG_BYTES);
	files.insert("test.png", PNG_BYTES);
	files.insert("test.pdf", PDF_BYTES);
	files.insert("test.zip", ZIP_BYTES);
	files.insert("wrong.jpg", PNG_BYTES);

	let dir = tempdir().expect("Failed to create temporary directory.");

	for (name, bytes) in &files {
		let mut file = File::create(dir.path().join(name)).expect(&*format!("Failed to create file: {}", name));

		file
			.write_all(bytes)
			.expect(&*format!("Failed to write to file: {}", name));
		drop(file);
	}

	let scan_opts = ScanOpts {
		hidden: true,
		extensionless: false,
		follow_symlinks: false,
	};

	let entries = scan_directory(&dir.path().to_path_buf(), None, None, &scan_opts).expect("Directory scan failed.");

	assert_eq!(entries.len(), files.len());

	// initialise global mime DB - this is needed because `scan_from_walkdir` expects it to be present.
	crate::init_db();

	let results = scan_from_walkdir(&entries);
	for result in results {
		// there should be no IO errors during this test. any IO errors encountered are outside the scope of this test.
		let result = result.expect("Error while scanning file");

		if !result.valid {
			// the only invalid file detected should be "wrong.jpg", which is a misnamed png file
			// 1. ensure detected extension is "jpg"
			assert_eq!(extension_from_path(&*result.file).unwrap(), OsStr::new("jpg"));
			// 2. ensure detected mime type is IMAGE_PNG
			assert_eq!(result.mime, IMAGE_PNG);
			// 3. ensure the recommended extension for "wrong.jpg" is "png"
			assert_eq!(&result.recommended_extension().unwrap(), &String::from("png"));
			continue;
		}

		// check if the recommended extension for this file is in the list of known extensions for its mimetype - for
		// example, if the file is determined to be an IMAGE_PNG, its recommended extension should be one of the extensions
		// returned by `mime_extension_lookup(IMAGE_PNG)`.
		assert!(mime_extension_lookup(result.mime.clone())
			.unwrap()
			.contains(&result.recommended_extension().unwrap()));

		// make sure the guessed mimetype is correct based on the extension of the scanned file
		// because we already know that the extensions match the mimetype (as we created these files ourselves earlier in
		// the test), all files with the "jpg" extension should be IMAGE_JPEGs, etc.
		let ext = extension_from_path(result.file);
		assert!(ext.is_some());
		assert_eq!(
			result.mime,
			match ext.unwrap().to_string_lossy().borrow() {
				"jpg" | "jpeg" => IMAGE_JPEG,
				"png" => IMAGE_PNG,
				"pdf" => APPLICATION_PDF,
				"zip" => application_zip(),
				_ => APPLICATION_OCTET_STREAM, // general "fallback" type
			},
			"Incorrect MIME type detected - got {:?} for a {:?} file",
			result.mime,
			ext.unwrap()
		);
	}
}

#[test]
/// Ensure that command line argument parsing works correctly - flags are interpreted, booleans are set, and so on.
fn argument_parsing() {
	use crate::parameters::{Parameters, ScanOpts};
	use clap::Clap;

	// pass `-f`, which enables following symlinks, and `-E images`, which scans files with image extensions
	let args: Parameters = Parameters::parse_from(vec!["fif", "-f", "-E", "images"]);

	// check if "jpg" is in the list of extensions to be scanned
	assert!(
		args
			.extensions()
			.expect("args.extensions() should be Some(_)!")
			.contains(&"jpg"),
		"args.extensions() should contain the `images` set!"
	);

	// make sure "scan_hidden" is false
	assert!(!args.scan_hidden);

	// exts should be none
	assert!(args.exts.is_none());

	// there shouldn't be any excluded extensions
	assert!(args.excluded_extensions().is_none());

	// get the ScanOpts, and make sure they match expectations
	assert_eq!(
		args.get_scan_opts(),
		ScanOpts {
			hidden: false,
			extensionless: false,
			follow_symlinks: true,
		},
		"ScanOpts are incorrect"
	)
}

#[test]
/// Ensure exclude overrides `-e` and `-E`.
fn exclude_overrides() {
	use crate::parameters::Parameters;
	use clap::Clap;

	// pass `-E images`, which includes many image extensions, and `-x jpg,png`, which should remove "jpg" and "png" from
	// the extensions list
	let args: Parameters = Parameters::parse_from(vec!["fif", "-x", "jpg,png", "-E", "images"]);
	let extensions = args.extensions();
	assert!(extensions.is_some(), "Extensions should contain the `images` set!");
	let extensions = extensions.unwrap();

	assert!(!extensions.contains(&"jpg"), "\"jpg\" should be excluded!");
	assert!(!extensions.contains(&"png"), "\"png\" should be excluded!");
	assert!(extensions.contains(&"jpeg"), "\"jpeg\" should be included!");

	// pass `-e abc,def,ghi,jkl` and `-x abc,def` -- extensions() should only contain "ghi" and "jkl"
	let args: Parameters = Parameters::parse_from(vec!["fif", "-e", "abc,def,ghi,jkl", "-x", "abc,def"]);
	let extensions = args.extensions();
	assert!(extensions.is_some(), "Extensions should be set!");
	let extensions = extensions.unwrap();

	assert!(!extensions.contains(&"abc"));
	assert!(!extensions.contains(&"def"));
	assert!(extensions.contains(&"ghi"));
	assert!(extensions.contains(&"jkl"));
}

#[test]
/// Ensure that badly formed command line arguments are rejected.
fn rejects_bad_args() {
	use crate::parameters::Parameters;

	use clap::Clap;
	let tests = [
		// Non-existent flags:
		vec!["fif", "-abcdefghijklmnopqrstuvwxyz"],
		// `-E` without specifying a set:
		vec!["fif", "-E"],
		// `-E` with an invalid set:
		vec!["fif", "-E", "pebis"],
		// `-E` and `-e`:
		vec!["fif", "-E", "media", "-e", "jpg"],
		// `-e` with nothing but commas:
		vec!["fif", "-e", ",,,,,"],
	];

	for test in &tests {
		assert!(Parameters::try_parse_from(test).is_err(), "Failed to reject {:?}", test);
	}
}

#[test]
/// Generate random series of bytes and try to identify them. This test makes no assertions and can only fail if the
/// mime database somehow panics or hangs.
fn identify_random_bytes() {
	let db = get_mime_db();
	let rng = fastrand::Rng::new();
	let mut bytes: Vec<u8>;
	let mut results: HashMap<Mime, i32> = HashMap::new();

	for _ in 1..500 {
		bytes = std::iter::repeat_with(|| rng.u8(..)).take(BUF_SIZE * 2).collect();
		if let Some(detected_type) = db.get_type(&*bytes) {
			*results.entry(detected_type).or_insert(0) += 1;
		}
	}

	for (mime, count) in &results {
		println!("{}:\t{} counts", mime, count);
	}
	println!("No type found:\t{} counts", 500 - results.values().sum::<i32>())
}

#[test]
/// Ensure that, for a given file "wrong.bad", which should have extension "good", the shell output contains something
/// like "mv wrong.bad wrong.good".
fn outputs_move_commands() {
	use std::io::Read;

	// create an example finding stating that "misnamed_file.png" has been identified as a jpeg file
	let entries = vec![Ok(Findings {
		file: Path::new("misnamed_file.png"),
		valid: false,
		mime: IMAGE_JPEG,
	})];

	let mut cursor = std::io::Cursor::new(Vec::new());
	let mut contents = std::string::String::new();

	Shell::new()
		.write_all(&entries, &mut cursor)
		.expect("Failed to write to cursor");
	cursor.set_position(0);
	cursor
		.read_to_string(&mut contents)
		.expect("Failed to read from cursor to string");

	// the output should contain a command like "mv -i misnamed_file.png misnamed_file.jpg"
	assert!(
		contents.contains("misnamed_file.jpg"),
		"Output doesn't contain move command!"
	)
}

#[test]
/// Ensure that the Media extension set contains all (is a superset) of Audio, Video, and Images.
fn media_contains_audio_video_images() {
	use crate::parameters::ExtensionSet::{Audio, Images, Media, Videos};
	let media_exts = Media.extensions();

	// assert every extension in the audio/video/image sets is contained in the media set
	[Audio.extensions(), Videos.extensions(), Images.extensions()]
		.concat()
		.into_iter()
		.for_each(|ext| assert!(media_exts.contains(&ext)));
}

#[test]
/// Ensure that the `writables!` macro produces the output it should.
fn writables_is_correct() {
	use crate::formats::Writable;
	use crate::writables;

	assert_eq!(
		&[
			"henlo".into(),
			Path::new("henlo").into(),
			Writable::Newline,
			Writable::Space
		],
		writables!["henlo", (Path::new("henlo")), Newline, Space]
	)
}