If just one of the range ends is negative, this now forces direction away from it.
I.e. if the beginning is negative, we go in reverse.
If the end is negative, we go forwards.
This fixes cases like
$var[2..-1]
if $var only has one element.
While supported by gcc and clang, \e is a gcc-specific extension and not
formally defined in the C or C++ standards.
See [0] for a list of valid escapes.
[0]: https://stackoverflow.com/a/10220539/17027
From the discussion in #3802, handling spaces within braces more
gracefully. Leading and trailing whitespace that isn't quoted or escaped
is stripped, whitespace in the middle is preserved. Any whitespace
encountered within expansion tokens is treated as a single space,
similar to how programming languages that don't hard break tokens/quotes
on line endings would.
This special cases expansion of $history variables, so that slicing
history no longer needs to construct the entire history array. Speedup
is around 100x in my test.
Fixes#4650
This eliminates the "missing" notion of env_var_t. Instead
env_get returns a maybe_t<env_var_t>, which forces callers to
handle the possibility that the variable is missing.
Internally fish should store vars as a vector of elements. The current
flat string representation is a holdover from when the code was written
in C.
Fixes#4200
Make the `env_var_t::missing_var()` object a singleton rather than a
dynamically constructed object. This requires some discipline in its use
since C++ doesn't directly support immutable objects. But it is slightly
more efficient and helps identify code that incorrectly mutates `env_var_t`
objects that should not be modified.
My previous change to eliminate `class var_entry_t` caused me to notice
that `env_get()` turned a set but empty var into a missing var. Which
is wrong. Fixing that brought to light several other pieces of code that
were wrong as a consequence of the aforementioned bug.
Another step to fixing issue #4200.
This is the first step to implementing issue #4200 is to stop subclassing
env_var_t from wcstring. Not too surprisingly doing this identified
several places that were incorrectly treating env_var_t and wcstring as
interchangeable types. I'm not talking about those places that passed
an env_var_t instance to a function that takes a wcstring. I'm talking
about doing things like assigning the former to the latter type, relying
on the implicit conversion, and thus losing information.
We also rename `env_get_string()` to `env_get()` for symmetry with
`env_set()` and to make it clear the function does not return a string.
This makes command substitutions impose the same limit on the amount
of data they accept as the `read` builtin. It does not limit output of
external commands or builtins in other contexts.
Fixes#3822
Rewrite the `abbr` function to store each abbreviation in a separate
variable. This greatly improves the efficiency. For the common case
it is 5x faster. For pathological cases it is upwards of 100x faster.
Most people should be able to unconditionally define abbreviations in
their config.fish without a noticable slow down.
Fixes#4048
In the rare case that we don't inherit $HOME _and_ can't read it from
/etc/passwd, this makes it so instead of triggering an assert() $HOME
is set to the empty list.
Tilde-expansion expands to nothing in such a case (and a string-empty
$HOME), `cd` errors out.
Fixes#4229.
This just removes every invalid index.
That means with `set foo a b c` and the "show" function from tests/expand.in:
- `show $foo[-5..-1]` prints "3 a b c"
- `show $foo[-10..1]` prints "1 a"
- `show $foo[2..5]` prints "2 b c"
- `show $foo[1 3 7 2]` prints "3 a c b"
and similar for command substitutions.
Fixes#826.
This is the first step in addressing issue #3965. It renames some of the
functions involved in validating variable and function names to clarify
their purpose. It also augments the documentation to make the rules for
such identifiers clearly documented.
There are at least three env vars describing a sequence of paths to be
searched where an empty path element is implicitly equivalent to ".".
This change converts the implicit "." to explicit whenever the variable
is imported or set. This makes the variable much easier to use in fish
scripts.
Fixes#3914
