This adds a path builtin to deal with paths.
It offers the following subcommands:
filter to go through a list of paths and only print the ones that pass some filter - exist, are a directory, have read permission, ...
is as a shortcut for filter -q to only return true if one of the paths passed the filter
basename, dirname and extension to print certain parts of the path
change-extension to change the extension to a different one (as a string operation)
normalize and resolve to canonicalize the paths in various flavors
sort to sort paths, also only using the basename or dirname as a key
The definition of "extension" here was carefully considered and should line up with how extensions are actually used - ~/.bashrc doesn't have an extension, but ~/.conf.d does (".d").
These subcommands all compose well - they can read from arguments or stdin (like string), they can use null-delimited input or output (input is autodetected - if a NULL happens in the first PATH_MAX bytes it switches automatically).
It is both a failglob exception (so like set if a glob passed to it fails it just doesn't get any arguments for it instead of triggering an error), and passes output to command substitution buffers explicitly split (like string split0) so newlines are easy to handle.
This would still remove non-existent paths, which isn't a strict
inversion and contradicts the docs.
Currently, to only allow paths that exist but don't pass a type check,
you'd have to filter twice:
path filter -Z foo bar | path filter -vfz
If a shortcut for this becomes necessary we can add it later.
This is now added to the two commands that definitely deal with
relative paths.
It doesn't work for e.g. `path basename`, because after removing the
dirname prepending a "./" doesn't refer to the same file, and the
basename is also expected to not contain any slashes.
Because we now count the extension including the ".", we print an
empty entry.
This makes e.g.
```fish
set -l base (path change-extension '' $somefile)
set -l ext (path extension $somefile)
echo $base$ext
```
reconstruct the filename, and makes it easier to deal with files with
no extension.
This means "../" components are cancelled out even after non-existent
paths or files.
(the alternative is to error out, but being able to say `path resolve
/path/to/file/../../` over `path resolve (path dirname
/path/to/file)/../../` seems worth it?)
Yeah, the macOS tests fail because it's started in /private/var... with a
$PWD of /var.... So resolve canonicalizes the path, which makes it no
longer match $PWD.
Simply use pwd -P
This just goes back until it finds an existent path, resolves that,
and adds the normalized rest on top.
So if you try
/bin/foo/bar////../baz
and /bin exists as a symlink to /usr/bin, it would resolve that, and
normalize the rest, giving
/usr/bin/foo/baz
(note: We might want to add this to realpath as well?)
This includes the "." in what `path extension` prints.
This allows distinguishing between an empty extension (just `.`) and a
non-existent extension (no `.` at all).
This adds a "path" builtin that can handle paths.
Implemented so far:
- "path filter PATHS", filters paths according to existence and optionally type and permissions
- "path base" and "path dir", run basename and dirname, respectively
- "path extension PATHS", prints the extension, if any
- "path strip-extension", prints the path without the extension
- "path normalize PATHS", normalizes paths - removing "/./" components
- and such.
- "path real", does realpath - i.e. normalizing *and* link resolution.
Some of these - base, dir, {strip-,}extension and normalize operate on the paths only as strings, so they handle nonexistent paths. filter and real ignore any nonexistent paths.
All output is split explicitly, so paths with newlines in them are
handled correctly. Alternatively, all subcommands have a "--null-input"/"-z" and "--null-output"/"-Z" option to handle null-terminated input and create null-terminated output. So
find . -print0 | path base -z
prints the basename of all files in the current directory,
recursively.
With "-Z" it also prints it null-separated.
(if stdout is going to a command substitution, we probably want to
skip this)
All subcommands also have a "-q"/"--quiet" flag that tells them to skip output. They return true "when something happened". For match/filter that's when a file passed, for "base"/"dir"/"extension"/"strip-extension" that's when something about the path *changed*.
Filtering
---------
`filter` supports all the file*types* `test` has - "dir", "file", "link", "block"..., as well as the permissions - "read", "write", "exec" and things like "suid".
It is missing the tty check and the check for the file being non-empty. The former is best done via `isatty`, the latter I don't think I've ever seen used.
There currently is no way to only get "real" files, i.e. ignore links pointing to files.
Examples
--------
> path real /bin///sh
/usr/bin/bash
> path extension foo.mp4
mp4
> path extension ~/.config
(nothing, because ".config" isn't an extension.)
This teaches `--on-signal SIGINT` (and by extension `trap cmd SIGINT`)
to work properly in scripts, not just interactively. Note any such
function will suppress the default behavior of exiting. Do this for
SIGTERM as well.
Like `set` and `read` before it, `eval` can be used to set variables,
and so it can't be shadowed by a function without loss of
functionality.
So this forbids it.
Incidentally, this means we will no longer try to autoload an
`eval.fish` file that's left over from an old version, which would
have helped with #8963.
Previously, running `fish_add_path /foo /foo` would result in /foo
being added to $PATH twice.
Now we check that it hasn't already been given, so we skip the
second (and any further) occurence.
This *might* be a bit faster running under TSAN, otherwise it takes >
400 seconds on Github Actions.
If this doesn't work we need to disable it for TSAN.
To recap, this means `&` in the middle of a word no longer
backgrounds.
So:
```fish
echo foo&bar # prints foo&bar
echo foo& bar # backgrounds an echo that prints "foo" and runs "bar"
```
This can no longer be changed. If "no-stderr-nocaret" is in
$fish_features it will simply be ignored.
The "^" redirection that was deprecated in fish 3.0 is now gone for good.
Note: For testing reasons, it can still be set _internally_ by running
"feature_flags_t::set". We simply shouldn't do that.
When you do
```fish
set foo-bar baz
```
"foo-baz" isn't usable as a variable *name*. When you just say the
"variable" is invalid that could also be interpreted to be a special
type of variable or something.
String tokens are subdivided by command substitutions. Some syntax errors
can occur in the gap between two command substitutions. Make the caret point
to the start of that gap, instead of the token start.
When expanding command substitutions, we use a naïve way of detecting whether
the cmdsub has the optional leading dollar. We check if the last character was
a dollar, which breaks if it's an escaped dollar. We wrongly expand
\$(echo "") to the empty string. Fix this by checking if the dollar was escaped.
The parse_util_* functions have a bunch of output parameters. We should
return a parameter bag instead (I think I tried once and failed).
Given
set var a
echo "$var$(echo b)"
the double-quoted string is expanded right-to-left, so we construct an
intermediate "$varb". Since the variable "varb" is undefined, this wrongly
expands to the empty string (should be "ab"). Fix this by isolating the
expanded command substitution internally. We do the same when handling
unquoted command substitutions.
Fixes#8849
The read test is now failing on GitHub actions even though it passes on
my Mac. It may be due to differences in dd between these two
environments. Stop using dd and just use head.
The read.fish check has a test where it limits the amount of data passed to
`read` to 8192 bytes, and verifies that fish reads exactly that amount.
This check occasionally fails on the OBS builds; it's very hard to repro a
failure locally, but I finally did it.
The amount of data written is limited via `yes` and `dd`:
yes $line | dd bs=1024 count=(math "$fish_read_limit / 1024")
The bug is that `dd` outputs a fixed number of "blocks" where a block
corresponds to a single read. As `yes` and `dd` are running concurrently,
it may happen that `dd` performs a short read; this then counts as a single
block. So `dd` may output less than the desired amount of data.
This can be verified by removing the 2>/dev/null redirection; on a
successful run dd reports `8+0 records out`, on a failed run it reports
`7+1 records out` because one of the records was short.
Fix this by using `fullblock` so that dd will no longer count a short read
as a single block. `head` would probably be a simpler tool to use but we'll
do this for now.
Happily it's not a fish bug. No need to relnote it.
This was already apparently supposed to work, but didn't because we
just overrode errno again.
This now means that, if a correctly named candidate exists, we don't
start the command-not-found handler.
See #8804
This used to call exec_subshell, which has two issues:
1. It creates a command substitution block which shows up in a stack
trace
2. It does much more work than necessary
This removes a useless "in command substitution" from an error message
in an autoloaded file, and it speeds up autoloading a bit (not
measurable in actual benchmarks, but microbenchmarks are 2x).
