exa/src/fs/filter.rs
Christian Göttsche 61ec153bcd Cleanup clippy warnings
warning: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
 --> src/output/escape.rs:4:1
  |
4 | pub fn escape<'a>(string: String, bits: &mut Vec<ANSIString<'a>>, good: Style, bad: Style) {
  | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |

warning: this lifetime isn't used in the function definition
 --> src/output/escape.rs:4:15
  |
4 | pub fn escape<'a>(string: String, bits: &mut Vec<ANSIString<'_>>, good: Style, bad: Style) {
  |               ^^
  |

warning: single-character string constant used as pattern
   --> src/output/table.rs:310:41
    |
310 |                     if file.starts_with(":") {
    |                                         ^^^ help: try using a `char` instead: `':'`
    |

warning: single-character string constant used as pattern
   --> src/output/table.rs:310:41
    |
310 |                     if file.starts_with(":") {
    |                                         ^^^ help: try using a `char` instead: `':'`
    |

warning: methods called `new` usually return `Self`
  --> src/output/render/git.rs:38:5
   |
38 |     fn new(&self) -> Style;
   |     ^^^^^^^^^^^^^^^^^^^^^^^
   |

warning: this lifetime isn't used in the function definition
  --> src/output/icons.rs:40:22
   |
40 | pub fn iconify_style<'a>(style: Style) -> Style {
   |                      ^^
   |

warning: lint `clippy::find_map` has been removed: this lint has been replaced by `manual_find_map`, a more specific lint
  --> src/main.rs:11:10
   |
11 | #![allow(clippy::find_map)]
   |          ^^^^^^^^^^^^^^^^
   |

warning: redundant else block
   --> src/fs/dir.rs:124:18
    |
124 |               else {
    |  __________________^
125 | |                 return None
126 | |             }
    | |_____________^
    |

warning: redundant else block
  --> src/options/view.rs:60:18
   |
60 |               else {
   |  __________________^
61 | |                 // the --tree case is handled by the DirAction parser later
62 | |                 return Ok(Self::Details(details));
63 | |             }
   | |_____________^
   |

warning: all variants have the same postfix: `Bytes`
   --> src/output/table.rs:170:1
    |
170 | / pub enum SizeFormat {
171 | |
172 | |     /// Format the file size using **decimal** prefixes, such as “kilo”,
173 | |     /// “mega”, or “giga”.
...   |
181 | |     JustBytes,
182 | | }
    | |_^
    |

warning: all variants have the same postfix: `Bytes`
   --> src/output/table.rs:171:1
    |
171 | / pub enum SizeFormat {
172 | |
173 | |     /// Format the file size using **decimal** prefixes, such as “kilo”,
174 | |     /// “mega”, or “giga”.
...   |
182 | |     JustBytes,
183 | | }
    | |_^
    |

warning: useless use of `format!`
   --> src/options/mod.rs:181:50
    |
181 |               return Err(OptionsError::Unsupported(format!(
    |  __________________________________________________^
182 | |                 "Options --git and --git-ignore can't be used because `git` feature was disabled in this build of exa"
183 | |             )));
    | |_____________^ help: consider using `.to_string()`: `"Options --git and --git-ignore can't be used because `git` feature was disabled in this build of exa".to_string()`
    |

warning: stripping a prefix manually
   --> src/fs/filter.rs:287:33
    |
287 |         if n.starts_with('.') { &n[1..] }
    |                                 ^^^^^^^
    |

warning: case-sensitive file extension comparison
  --> src/info/filetype.rs:24:19
   |
24 |         file.name.ends_with(".ninja") ||
   |                   ^^^^^^^^^^^^^^^^^^^
   |
2021-04-30 15:37:31 +02:00

416 lines
15 KiB
Rust
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

//! Filtering and sorting the list of files before displaying them.
use std::cmp::Ordering;
use std::iter::FromIterator;
use std::os::unix::fs::MetadataExt;
use std::path::Path;
use crate::fs::DotFilter;
use crate::fs::File;
/// The **file filter** processes a list of files before displaying them to
/// the user, by removing files they dont want to see, and putting the list
/// in the desired order.
///
/// Usually a user does not want to see *every* file in the list. The most
/// common case is to remove files starting with `.`, which are designated
/// as hidden files.
///
/// The special files `.` and `..` files are not actually filtered out, but
/// need to be inserted into the list, in a special case.
///
/// The filter also governs sorting the list. After being filtered, pairs of
/// files are compared and sorted based on the result, with the sort field
/// performing the comparison.
#[derive(PartialEq, Debug, Clone)]
pub struct FileFilter {
/// Whether directories should be listed first, and other types of file
/// second. Some users prefer it like this.
pub list_dirs_first: bool,
/// The metadata field to sort by.
pub sort_field: SortField,
/// Whether to reverse the sorting order. This would sort the largest
/// files first, or files starting with Z, or the most-recently-changed
/// ones, depending on the sort field.
pub reverse: bool,
/// Whether to only show directories.
pub only_dirs: bool,
/// Which invisible “dot” files to include when listing a directory.
///
/// Files starting with a single “.” are used to determine “system” or
/// “configuration” files that should not be displayed in a regular
/// directory listing, and the directory entries “.” and “..” are
/// considered extra-special.
///
/// This came about more or less by a complete historical accident,
/// when the original `ls` tried to hide `.` and `..`:
/// https://plus.google.com/+RobPikeTheHuman/posts/R58WgWwN9jp
///
/// When one typed ls, however, these files appeared, so either Ken or
/// Dennis added a simple test to the program. It was in assembler then,
/// but the code in question was equivalent to something like this:
/// if (name[0] == '.') continue;
/// This statement was a little shorter than what it should have been,
/// which is:
/// if (strcmp(name, ".") == 0 || strcmp(name, "..") == 0) continue;
/// but hey, it was easy.
///
/// Two things resulted.
///
/// First, a bad precedent was set. A lot of other lazy programmers
/// introduced bugs by making the same simplification. Actual files
/// beginning with periods are often skipped when they should be counted.
///
/// Second, and much worse, the idea of a "hidden" or "dot" file was
/// created. As a consequence, more lazy programmers started dropping
/// files into everyone's home directory. I don't have all that much
/// stuff installed on the machine I'm using to type this, but my home
/// directory has about a hundred dot files and I don't even know what
/// most of them are or whether they're still needed. Every file name
/// evaluation that goes through my home directory is slowed down by
/// this accumulated sludge.
pub dot_filter: DotFilter,
/// Glob patterns to ignore. Any file name that matches *any* of these
/// patterns wont be displayed in the list.
pub ignore_patterns: IgnorePatterns,
/// Whether to ignore Git-ignored patterns.
/// This is implemented completely separately from the actual Git
/// repository scanning — a `.gitignore` file will still be scanned even
/// if theres no `.git` folder present.
pub git_ignore: GitIgnore,
}
impl FileFilter {
/// Remove every file in the given vector that does *not* pass the
/// filter predicate for files found inside a directory.
pub fn filter_child_files(&self, files: &mut Vec<File<'_>>) {
files.retain(|f| ! self.ignore_patterns.is_ignored(&f.name));
if self.only_dirs {
files.retain(File::is_directory);
}
}
/// Remove every file in the given vector that does *not* pass the
/// filter predicate for file names specified on the command-line.
///
/// The rules are different for these types of files than the other
/// type because the ignore rules can be used with globbing. For
/// example, running `exa -I='*.tmp' .vimrc` shouldnt filter out the
/// dotfile, because its been directly specified. But running
/// `exa -I='*.ogg' music/*` should filter out the ogg files obtained
/// from the glob, even though the globbing is done by the shell!
pub fn filter_argument_files(&self, files: &mut Vec<File<'_>>) {
files.retain(|f| {
! self.ignore_patterns.is_ignored(&f.name)
});
}
/// Sort the files in the given vector based on the sort field option.
pub fn sort_files<'a, F>(&self, files: &mut Vec<F>)
where F: AsRef<File<'a>>
{
files.sort_by(|a, b| {
self.sort_field.compare_files(a.as_ref(), b.as_ref())
});
if self.reverse {
files.reverse();
}
if self.list_dirs_first {
// This relies on the fact that `sort_by` is *stable*: it will keep
// adjacent elements next to each other.
files.sort_by(|a, b| {
b.as_ref().points_to_directory()
.cmp(&a.as_ref().points_to_directory())
});
}
}
}
/// User-supplied field to sort by.
#[derive(PartialEq, Debug, Copy, Clone)]
pub enum SortField {
/// Dont apply any sorting. This is usually used as an optimisation in
/// scripts, where the order doesnt matter.
Unsorted,
/// The file name. This is the default sorting.
Name(SortCase),
/// The files extension, with extensionless files being listed first.
Extension(SortCase),
/// The files size, in bytes.
Size,
/// The files inode, which usually corresponds to the order in which
/// files were created on the filesystem, more or less.
FileInode,
/// The time the file was modified (the “mtime”).
///
/// As this is stored as a Unix timestamp, rather than a local time
/// instance, the time zone does not matter and will only be used to
/// display the timestamps, not compare them.
ModifiedDate,
/// The time the file was accessed (the “atime”).
///
/// Oddly enough, this field rarely holds the *actual* accessed time.
/// Recording a read time means writing to the file each time its read
/// slows the whole operation down, so many systems will only update the
/// timestamp in certain circumstances. This has become common enough that
/// its now expected behaviour!
/// http://unix.stackexchange.com/a/8842
AccessedDate,
/// The time the file was changed (the “ctime”).
///
/// This field is used to mark the time when a files metadata
/// changed — its permissions, owners, or link count.
///
/// In original Unix, this was, however, meant as creation time.
/// https://www.bell-labs.com/usr/dmr/www/cacm.html
ChangedDate,
/// The time the file was created (the “btime” or “birthtime”).
CreatedDate,
/// The type of the file: directories, links, pipes, regular, files, etc.
///
/// Files are ordered according to the `PartialOrd` implementation of
/// `fs::fields::Type`, so changing that will change this.
FileType,
/// The “age” of the file, which is the time it was modified sorted
/// backwards. The reverse of the `ModifiedDate` ordering!
///
/// It turns out that listing the most-recently-modified files first is a
/// common-enough use case that it deserves its own variant. This would be
/// implemented by just using the modified date and setting the reverse
/// flag, but this would make reversing *that* output not work, which is
/// bad, even though thats kind of nonsensical. So its its own variant
/// that can be reversed like usual.
ModifiedAge,
/// The file's name, however if the name of the file begins with `.`
/// ignore the leading `.` and then sort as Name
NameMixHidden(SortCase),
}
/// Whether a field should be sorted case-sensitively or case-insensitively.
/// This determines which of the `natord` functions to use.
///
/// I kept on forgetting which one was sensitive and which one was
/// insensitive. Would a case-sensitive sort put capital letters first because
/// it takes the case of the letters into account, or intermingle them with
/// lowercase letters because it takes the difference between the two cases
/// into account? I gave up and just named these two variants after the
/// effects they have.
#[derive(PartialEq, Debug, Copy, Clone)]
pub enum SortCase {
/// Sort files case-sensitively with uppercase first, with A coming
/// before a.
ABCabc,
/// Sort files case-insensitively, with A being equal to a.
AaBbCc,
}
impl SortField {
/// Compares two files to determine the order they should be listed in,
/// depending on the search field.
///
/// The `natord` crate is used here to provide a more *natural* sorting
/// order than just sorting character-by-character. This splits filenames
/// into groups between letters and numbers, and then sorts those blocks
/// together, so `file10` will sort after `file9`, instead of before it
/// because of the `1`.
pub fn compare_files(self, a: &File<'_>, b: &File<'_>) -> Ordering {
use self::SortCase::{ABCabc, AaBbCc};
match self {
Self::Unsorted => Ordering::Equal,
Self::Name(ABCabc) => natord::compare(&a.name, &b.name),
Self::Name(AaBbCc) => natord::compare_ignore_case(&a.name, &b.name),
Self::Size => a.metadata.len().cmp(&b.metadata.len()),
Self::FileInode => a.metadata.ino().cmp(&b.metadata.ino()),
Self::ModifiedDate => a.modified_time().cmp(&b.modified_time()),
Self::AccessedDate => a.accessed_time().cmp(&b.accessed_time()),
Self::ChangedDate => a.changed_time().cmp(&b.changed_time()),
Self::CreatedDate => a.created_time().cmp(&b.created_time()),
Self::ModifiedAge => b.modified_time().cmp(&a.modified_time()), // flip b and a
Self::FileType => match a.type_char().cmp(&b.type_char()) { // todo: this recomputes
Ordering::Equal => natord::compare(&*a.name, &*b.name),
order => order,
},
Self::Extension(ABCabc) => match a.ext.cmp(&b.ext) {
Ordering::Equal => natord::compare(&*a.name, &*b.name),
order => order,
},
Self::Extension(AaBbCc) => match a.ext.cmp(&b.ext) {
Ordering::Equal => natord::compare_ignore_case(&*a.name, &*b.name),
order => order,
},
Self::NameMixHidden(ABCabc) => natord::compare(
Self::strip_dot(&a.name),
Self::strip_dot(&b.name)
),
Self::NameMixHidden(AaBbCc) => natord::compare_ignore_case(
Self::strip_dot(&a.name),
Self::strip_dot(&b.name)
)
}
}
fn strip_dot(n: &str) -> &str {
match n.strip_prefix('.') {
Some(s) => s,
None => n,
}
}
}
/// The **ignore patterns** are a list of globs that are tested against
/// each filename, and if any of them match, that file isnt displayed.
/// This lets a user hide, say, text files by ignoring `*.txt`.
#[derive(PartialEq, Default, Debug, Clone)]
pub struct IgnorePatterns {
patterns: Vec<glob::Pattern>,
}
impl FromIterator<glob::Pattern> for IgnorePatterns {
fn from_iter<I>(iter: I) -> Self
where I: IntoIterator<Item = glob::Pattern>
{
let patterns = iter.into_iter().collect();
Self { patterns }
}
}
impl IgnorePatterns {
/// Create a new list from the input glob strings, turning the inputs that
/// are valid glob patterns into an `IgnorePatterns`. The inputs that
/// dont parse correctly are returned separately.
pub fn parse_from_iter<'a, I: IntoIterator<Item = &'a str>>(iter: I) -> (Self, Vec<glob::PatternError>) {
let iter = iter.into_iter();
// Almost all glob patterns are valid, so its worth pre-allocating
// the vector with enough space for all of them.
let mut patterns = match iter.size_hint() {
(_, Some(count)) => Vec::with_capacity(count),
_ => Vec::new(),
};
// Similarly, assume there wont be any errors.
let mut errors = Vec::new();
for input in iter {
match glob::Pattern::new(input) {
Ok(pat) => patterns.push(pat),
Err(e) => errors.push(e),
}
}
(Self { patterns }, errors)
}
/// Create a new empty set of patterns that matches nothing.
pub fn empty() -> Self {
Self { patterns: Vec::new() }
}
/// Test whether the given file should be hidden from the results.
fn is_ignored(&self, file: &str) -> bool {
self.patterns.iter().any(|p| p.matches(file))
}
/// Test whether the given file should be hidden from the results.
pub fn is_ignored_path(&self, file: &Path) -> bool {
self.patterns.iter().any(|p| p.matches_path(file))
}
// TODO(ogham): The fact that `is_ignored_path` is pub while `is_ignored`
// isnt probably means its in the wrong place
}
/// Whether to ignore or display files that are mentioned in `.gitignore` files.
#[derive(PartialEq, Debug, Copy, Clone)]
pub enum GitIgnore {
/// Ignore files that Git would ignore. This means doing a check for a
/// `.gitignore` file, possibly recursively up the filesystem tree.
CheckAndIgnore,
/// Display files, even if Git would ignore them.
Off,
}
// This is not fully baked yet. The `ignore` crate lists a lot more files that
// we arent checking:
//
// > By default, all ignore files found are respected. This includes .ignore,
// > .gitignore, .git/info/exclude and even your global gitignore globs,
// > usually found in $XDG_CONFIG_HOME/git/ignore.
#[cfg(test)]
mod test_ignores {
use super::*;
#[test]
fn empty_matches_nothing() {
let pats = IgnorePatterns::empty();
assert_eq!(false, pats.is_ignored("nothing"));
assert_eq!(false, pats.is_ignored("test.mp3"));
}
#[test]
fn ignores_a_glob() {
let (pats, fails) = IgnorePatterns::parse_from_iter(vec![ "*.mp3" ]);
assert!(fails.is_empty());
assert_eq!(false, pats.is_ignored("nothing"));
assert_eq!(true, pats.is_ignored("test.mp3"));
}
#[test]
fn ignores_an_exact_filename() {
let (pats, fails) = IgnorePatterns::parse_from_iter(vec![ "nothing" ]);
assert!(fails.is_empty());
assert_eq!(true, pats.is_ignored("nothing"));
assert_eq!(false, pats.is_ignored("test.mp3"));
}
#[test]
fn ignores_both() {
let (pats, fails) = IgnorePatterns::parse_from_iter(vec![ "nothing", "*.mp3" ]);
assert!(fails.is_empty());
assert_eq!(true, pats.is_ignored("nothing"));
assert_eq!(true, pats.is_ignored("test.mp3"));
}
}