Given
set var a
echo "$var$(echo b)"
the double-quoted string is expanded right-to-left, so we construct an
intermediate "$varb". Since the variable "varb" is undefined, this wrongly
expands to the empty string (should be "ab"). Fix this by isolating the
expanded command substitution internally. We do the same when handling
unquoted command substitutions.
Fixes#8849
We don't want to convert the input to a "wcstring &" because
"stage_variables" needs to have the same type as other stages, so we
can use it in a loop. Communicate that to clang-tidy.
We also don't want to take "wcstring &&". As the Google style guide
states, it's not really beneficial here, and it potentially hurts
readability because it's a relatively obscure feature.
The rest of our code contains a bunch of && parameters. We might
want to get rid of some of them.
Closes#8227
This adds a hack to the parser. Given a command
echo "x$()y z"
we virtually insert double quotes before and after the command
substitution, so the command internally looks like
echo "x"$()"y z"
This hack allows to reuse the existing logic for handling (recursive)
command substitutions.
This makes the quoting syntax more complex; external highlighters
should consider adding this if possible.
The upside (more Bash compatibility) seems worth it.
Closes#159
Expansion parses slices like "$PATH[1..2]", but so does "set" when assigning
"set PATH[1..2] . .". Commit be06f842a ("Allow to omit indices in index
range expansions") forgot the latter.
Prior to this change, histories were immortal and allocated with either
unique_ptr or just leaked via new. But this can result in races in the
path detection test, as the destructor races with the pointer-captured
history. Switch to using shared_ptr.
Before running a command, or before importing a command from bash history,
we perform error checking. As part of error checking we expand commands
including variables and globs. If the glob is very large, like `/**`, then
we could hang expanding it.
One fix would be to limit the amount of expansion from the glob, but
instead let's just not expand command globs when performing error checking.
Fixes#7407
If the user types something like `/**`, prior to this change we would
attempt to expand it in the background for both highlighting and
autosuggestions. This could thrash your disk and also consume a lot of
memory.
Add a a field to operation_context_t to allow specifying a limit, and add
a "default background" limit of 512 items.
This adds the ability to limit how many expansions are produced. For
example if $big contains 10 items, and is Cartesian-expanded as
$big$big$big$big... 10 times, we would naviely get 10^10 = 10 billion
results, which fish can't actually handle. Implement this in
completion_receiver_t, which now can return false to indicate an overflow.
The initial expansion limit 'k_default_expansion_limit' is set as 512k
items. There's no way for users to change this at present.
This switches certain uses from just appending to a list to using
completion_receiver_t, in preparation for limiting how many completions
may be produced. Perhaps in time this could also be used for "streaming"
completions.
completion_receiver_t wraps a completion list; it will centralize logic
around adding completions and most importantly it will enforce that we
do not exceed our expansion limit.
When expanding a string, you may or may not want to generate
descriptions alongside the expanded string. Usually you don't want to
but descriptions were opt out. This commit makes them opt in.
Initially I wanted to pick a different name to avoid confusion with
process groups, but really job trees *are* process groups. So name them
to reflect that fact.
Also rename "placeholder" to "internal" which is clearer.
Job trees come in two flavors: “placeholders” for jobs which are only fish
functions, and non-placeholders which need to track a pgid. This adds
logic to allow a job to decide if its parent's job tree is appropriate,
and allocating a new tree if not.
Give string expansion an (optional) parent pgroup. This is threaded all
the way into eval(). This ensures that in a mixed pipeline like:
cmd | begin ; something (cmd2) ; end
that cmd2 and cmd have the same pgroup.
Add a test to ensure that command substitutions inherit pgroups
properly.
Fixes#6624
We had previously added a more helpful error message when a literal zero
index was specified when indexing into an array. This patch extends that
coverage to cases indexing into a command substitution, e.g.
```fish
echo (printf "hello\nworld\n")[0]
```
Mostly line breaks, one instance of tabs!
For some reason clang-format insists on two spaces before a same-line comment?
(I continue to be unimpressed with super-strict line length limits,
but I continue to believe in automatic styling, so it is what it is)
[ci skip]
When building fish-shell with the macOS 10.12 SDK, <sys/proc.h> does not
include <sys/time.h> but references `struct itimerval`. This causes a
compilation failure if we don't import <sys/time.h> ourselves.
This was previously masked by an import of <sys/sysctl.h>, which was
removed in fc0c39b6fd.
Glob ordering is used in a variety of places, including figuring out
conf.d and really needs to be stable.
Other ordering, like completions, is really just cosmetic and can
change if it makes for a nicer experience.
So we uncouple it by copying the wcsfilecmp from 3.0.2, which will
return the ordering to what it was in that release.
Fixes#6593
Prior to this fix, fish was rather inconsistent in when $status gets set
in response to an error. For example, a failed expansion like "$foo["
would not modify $status.
This makes the following inter-related changes:
1. String expansion now directly returns the value to set for $status on
error. The value is always used.
2. parser_t::eval() now directly returns the proc_status_t, which cleans
up a lot of call sites.
3. We expose a new function exec_subshell_for_expand() which ignores
$status but returns errors specifically related to subshell expansion.
4. We reify the notion of "expansion breaking" errors. These include
command-not-found, expand syntax errors, and others.
The upshot is we are more consistent about always setting $status on
errors.
This commit recognizes an existing pattern: many operations need some
combination of a set of variables, a way to detect cancellation, and
sometimes a parser. For example, tab completion needs a parser to execute
custom completions, the variable set, should cancel on SIGINT. Background
autosuggestions don't need a parser, but they do need the variables and
should cancel if the user types something new. Etc.
This introduces a new triple operation_context_t that wraps these concepts
up. This simplifies many method signatures and argument passing.
