Prior to this commit, setting a universal variable may trigger syncing
against the file which will modify other universal variables. But if we
want to support multiple environments we need the parser to decide when to
sync uvars. Shift the decision of when to sync to the parser itself. When a
universal variable is modified, now we just set a flag and it's up to the
(main) parser when to pick it up. This is hopefully just a refactoring with
no user-visible changes.
This makes it so `complete -c foo -n test1 -n test2` registers *both*
conditions, and when it comes time to check the candidate, tries both,
in that order. If any fails it stops, if all succeed the completion is offered.
The reason for this is that it helps with caching - we have a
condition cache, but conditions like
```fish
test (count (commandline -opc)) -ge 2; and contains -- (commandline -opc)[2] length
test (count (commandline -opc)) -ge 2; and contains -- (commandline -opc)[2] sub
```
defeats it pretty easily, because the cache only looks at the entire
script as a string - it can't tell that the first `test` is the same
in both.
So this means we separate it into
```fish
complete -f -c string -n "test (count (commandline -opc)) -ge 2; and contains -- (commandline -opc)[2] length" -s V -l visible -d "Use the visible width, excluding escape sequences"
+complete -f -c string -n "test (count (commandline -opc)) -ge 2" -n "contains -- (commandline -opc)[2] length" -s V -l visible -d "Use the visible width, excluding escape sequences"
```
which allows the `test` to be cached.
In tests, this improves performance for the string completions by 30%
by reducing all the redundant `test` calls.
The `git` completions can also greatly benefit from this.
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?)
This sorts paths by basename, dirname or full path - in future
possibly size or age.
It takes --invert to invert the sort and "--what=basename|dirname|..."
to specify what to sort
This can be used to implement better conf.d sorting, with something
like
```fish
set -l sourcelist
for file in (path sort --what=basename $__fish_config_dir/conf.d/*.fish $__fish_sysconf_dir/conf.d/*.fish $vendor_confdirs/*.fish)
```
which will iterate over the files by their basename. Then we keep a
list of their basenames to skip over anything that was already
sourced, like before.
The recent change to skip the newline for `string` changed this, and
it also hit builtin path (which is in development separately, so it's
not like it broke master).
Let's pick a good default here.
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).
These are short flags for "--perm=read" and "--type=link" and such.
Not every type or permission has a shorthand - we don't want "-s" for
"suid". So just the big three each get one.
This is needed because you might feasibly give e.g. `path filter`
globs to further match, and they might already present no results.
It's also well-handled since path simply does nothing if given no paths.
These were officially called "--null-input", but I just used
"--null-in" everywhere, which worked because getopt allows unambiguous abbreviations.
But since *I* couldn't keep it straight and the "put" is just
superfluous, let's remove it.
This is theoretically sound, because a path can only be PATH_MAX - 1
bytes long, so at least the PATH_MAXest byte needs to be a NULL.
The one case this could break is when something has a NULL-output mode
but doesn't bother printing the NULL for only one path, and that path
contains a newline. So we leave --null-in there, to force it on.
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.
s_observed_signals is used to inform the signal handler which signals may
have --on-signal functions attached to them, as an optimization. Prior to
this change it was latched: once we started observing a signal we assume we
will keep observing that signal. Make it properly increment and decrement,
in preparation for making trap work non-interactively.
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.
