Update dependencies
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0eac290..2cf79fd 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,8 @@
+## 2.0.1
+
+- Use extension type to represent `MaybeTarFormat` and `TarFormat`.
+- Update to version `6.0.0` of `package:lints`.
+
## 2.0.0
- Require the `mode` parameter when creating `TarHeader`s. Previously the field
diff --git a/lib/src/format.dart b/lib/src/format.dart
index b584f5c..273db1d 100644
--- a/lib/src/format.dart
+++ b/lib/src/format.dart
@@ -1,38 +1,23 @@
/// Holds the possible TAR formats that a file could take.
///
-/// This library supports the V7, USTAR, PAX, GNU, and STAR formats. The
-/// [MaybeTarFormat] class generally describes any combination of those formats
+/// This package supports the V7, USTAR, PAX, GNU, and STAR formats. The
+/// [TarFormat] class generally describes any combination of those formats
/// and represents that we don't know the exact format yet. As soon as we do
/// know, the [TarFormat] enum represents the exact format of a header.
-sealed class MaybeTarFormat {
- /// The TAR formats are encoded in powers of two in [_value], such that we
- /// can refine our guess via bit operations as we discover more information
- /// about the TAR file.
- /// A value of 0 means that the format is invalid.
- int get _value;
-
- factory MaybeTarFormat._(int value) {
- return switch (value) {
- 1 => TarFormat.v7,
- 2 => TarFormat.ustar,
- 4 => TarFormat.pax,
- 8 => TarFormat.gnu,
- 16 => TarFormat.star,
- final other => _MaybeTarFormat(other),
- };
- }
-
- /// Returns a new [MaybeTarFormat] that signifies that it can be either
- /// `this` or [other]'s format.
+extension type const MaybeTarFormat._(int _representation) {
+ /// Returns a new [TarFormat] that signifies that it can be either `this` or
+ /// or [other]'s format.
///
/// **Example:**
/// ```dart
- /// TarFormat format = TarFormat.ustar | TarFormat.pax;
+ /// MaybeTarFormat format = TarFormat.ustar | TarFormat.pax;
/// ```
///
/// The above code would signify that we have limited `format` to either
/// the USTAR or PAX format, but need further information to refine the guess.
- MaybeTarFormat operator |(TarFormat other);
+ MaybeTarFormat operator |(TarFormat other) {
+ return MaybeTarFormat._(_representation | other._representation);
+ }
/// Returns if [other] is a possible resolution of `this`.
///
@@ -40,7 +25,13 @@
/// enough information to determine if it is [TarFormat.ustar] or
/// [TarFormat.pax], so either of them could be possible resolutions of
/// `this`.
- bool has(MaybeTarFormat other);
+ bool has(MaybeTarFormat other) {
+ if (isKnownFormat) {
+ return this == other;
+ } else {
+ return mayOnlyBe(other).valid;
+ }
+ }
/// Returns a new [TarFormat] that signifies that it can only be [other]'s
/// format.
@@ -57,20 +48,51 @@
///
/// If `has(other) == false`, [mayOnlyBe] will result in an unknown
/// [TarFormat].
- MaybeTarFormat mayOnlyBe(MaybeTarFormat other);
+ MaybeTarFormat mayOnlyBe(MaybeTarFormat other) {
+ return MaybeTarFormat._(_representation & other._representation);
+ }
/// Returns if this format might be valid.
///
/// This returns true as well even if we have yet to fully determine what the
/// format is.
- bool get valid;
+ bool get valid => _representation != 0;
+
+ /// Whether this represents a single known format (as a value listed in
+ /// [TarFormat]).
+ bool get isKnownFormat =>
+ valid && _representation == 1 << (_representation.bitLength - 1);
+
+ String get description {
+ if (!valid) {
+ return 'Invalid';
+ }
+
+ final buffer = StringBuffer();
+
+ var repr = _representation;
+ for (final name in TarFormat._names) {
+ if (repr.isOdd) {
+ if (buffer.isNotEmpty) buffer.write(' or ');
+ buffer.write(name);
+ }
+
+ repr >>>= 1;
+ }
+
+ return buffer.toString();
+ }
}
/// A fully resolved tar format.
///
-/// When we know that a tar entry must use a specific format, this is represented
-/// with a value from this [TarFormat] enum.
-enum TarFormat implements MaybeTarFormat {
+/// When we know that a tar entry must use a specific format, this is
+/// represented with a value from this [TarFormat].
+extension type const TarFormat._(MaybeTarFormat _inner)
+ implements MaybeTarFormat {
+ // Names of known formats in order of their bit representation.
+ static const _names = ['V7', 'USTAR', 'PAX', 'GNU', 'STAR'];
+
/// Original Unix Version 7 (V7) AT&T tar tool prior to standardization.
///
/// The structure of the V7 Header consists of the following:
@@ -95,7 +117,7 @@
/// https://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5&format=html
/// https://www.gnu.org/software/tar/manual/html_chapter/tar_15.html#SEC188
/// http://cdrtools.sourceforge.net/private/man/star/star.4.html
- v7(1, 'V7'),
+ static const v7 = TarFormat._(MaybeTarFormat._(1));
/// USTAR (Unix Standard TAR) header format defined in POSIX.1-1988.
///
@@ -141,7 +163,7 @@
/// https://www.freebsd.org/cgi/man.cgi?query=tar&sektion=5&format=html
/// https://www.gnu.org/software/tar/manual/html_chapter/tar_15.html#SEC188
/// http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06
- ustar(2, 'USTAR'),
+ static const ustar = TarFormat._(MaybeTarFormat._(2));
/// PAX header format defined in POSIX.1-2001.
///
@@ -159,7 +181,7 @@
/// https://www.gnu.org/software/tar/manual/html_chapter/tar_15.html#SEC188
/// http://cdrtools.sourceforge.net/private/man/star/star.4.html
/// http://pubs.opengroup.org/onlinepubs/009695399/utilities/pax.html
- pax(4, 'PAX'),
+ static const pax = TarFormat._(MaybeTarFormat._(4));
/// GNU header format.
///
@@ -209,7 +231,7 @@
///
/// Reference:
/// https://www.gnu.org/software/tar/manual/html_node/Standard.html
- gnu(8, 'GNU'),
+ static const gnu = TarFormat._(MaybeTarFormat._(8));
/// Schily's TAR format, which is incompatible with USTAR.
/// This does not cover STAR extensions to the PAX format; these fall under
@@ -247,76 +269,5 @@
///
/// Reference:
/// http://cdrtools.sourceforge.net/private/man/star/star.4.html
- star(16, 'STAR'),
- ;
-
- @override
- final int _value;
-
- final String _name;
-
- const TarFormat(this._value, this._name);
-
- @override
- bool get valid => true;
-
- @override
- MaybeTarFormat operator |(TarFormat other) {
- return other == this ? this : _MaybeTarFormat(_value | other._value);
- }
-
- @override
- bool has(MaybeTarFormat other) {
- return other == this;
- }
-
- @override
- MaybeTarFormat mayOnlyBe(MaybeTarFormat other) {
- return MaybeTarFormat._(_value & other._value);
- }
-
- @override
- String toString() => _name;
-}
-
-final class _MaybeTarFormat implements MaybeTarFormat {
- // Note: We never represent a single tar format in a _MaybeTarFormat, these
- // are represented in the TarFormat enum.
- @override
- final int _value;
-
- const _MaybeTarFormat(this._value);
-
- @override
- int get hashCode => _value;
-
- @override
- bool operator ==(Object other) {
- if (other is! TarFormat) return false;
-
- return _value == other._value;
- }
-
- @override
- String toString() {
- if (!valid) return 'Invalid';
-
- return TarFormat.values.where(has).map((e) => e._name).join(' or ');
- }
-
- @override
- bool has(MaybeTarFormat other) => _value & other._value != 0;
-
- @override
- bool get valid => _value != 0;
-
- @override
- MaybeTarFormat mayOnlyBe(MaybeTarFormat other) {
- return MaybeTarFormat._(_value & other._value);
- }
-
- @override
- MaybeTarFormat operator |(TarFormat other) {
- return MaybeTarFormat._(_value | other._value);
- }
+ static const star = TarFormat._(MaybeTarFormat._(16));
}
diff --git a/pubspec.yaml b/pubspec.yaml
index 54bbf5d..64ca872 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,6 +1,6 @@
name: tar
description: Memory-efficient, streaming implementation of the tar file format
-version: 2.0.0
+version: 2.0.1
repository: https://github.com/simolus3/tar/
topics:
- tar
@@ -16,7 +16,7 @@
dev_dependencies:
charcode: ^1.2.0
- lints: ^5.0.0
+ lints: ^6.0.0
file: ^7.0.0
path: ^1.8.0
test: ^1.20.0
diff --git a/test/format_test.dart b/test/format_test.dart
index c42d68f..b74a3bf 100644
--- a/test/format_test.dart
+++ b/test/format_test.dart
@@ -35,7 +35,7 @@
TypeMatcher<MaybeTarFormat> _isFormat(String representation) {
return isA<MaybeTarFormat>()
- .having((e) => e.toString(), 'toString()', representation);
+ .having((e) => e.description, 'description', representation);
}
TypeMatcher<MaybeTarFormat> get _isInvalid {
