56d9134534 contained an LRU cache plus
changes to the documentation; 95162ef19d
reverted both.
This commit re-adds the documentation changes, which are still correct.
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.
maybe_t is an implementation of the Maybe/Optional type, allowing
for an optional value to be stored. This will enable a more
principled approach for functions that return values or failure,
such as env_get.
This commit backs out certain optimizations around setting environment
variables, and replaces them with move semantics. env_set accepts a
list, by value, permitting callers to use std::move to transfer
ownership.
Commit f872f25f introduced a freed memory access regression on line 460
of env.cpp, where an environment variable was converted to a temporary
string, the .c_str() address of which was stored while the string
temporary was destroyed.
This commit keeps a reference to the original string lying around so
that the c_str() pointer does not point to freed memory.
Valgrind warns that the sometimes uninitialized sigaction.sa_flags field
is sometimes used when passed to the signal handler.
This patch explicitly zeros out the sigaction.sa_flags field at creation
time.
Valgrind warns that the sometimes uninitialized sigaction.sa_flags field
is sometimes used when passed to the signal handler.
This patch explicitly zeros out the sigaction.sa_flags field at creation
time.
cherry-picked from krader1961/fish-shell commit b69df4fe72
Fixes#4353 (regression in indexing of history contents) and introduces
new unit tests to catch bad $history indexing in the future.
Using bare vars is more efficient because it makes the builtin `math`
expression cache more useful. That's because if you prefix each var with
a dollar-sign then the fish parser expands it before `math` is run.
Something like `math x + 1` can be cached since the expression is the
same each time it is run. But if you do `math $x + 1` and x==1 then you're
effectively executing `math 1 + 1`. And if x==2 the next time then you're
running `math 2 + 1`. Which makes the expression cache much less effective.
This implements an LRU cache of recently seen math expressions. When
executing math inside loops and the like this can provide a 33% decrease
in the time to execute the `math` command.
Remove our `math` function that wraps `bc`. Our math builtin is now good
enough that it can be the default implementation.
Another step in resolving #3157.
We need our `math` builtin to behave like `bc` with respect to rounding
floating point values to integer to avoid breaking to many existing
uses. So when scale is zero round down to the nearest integer.
Another change for #3157.
The MuParser supports the concept of multiple expressions separated by
commas. This implements support for that so that you can do things like
this:
set results (math '1+1, 4*2, 9^2')
This is the second baby step in resolving #3157. Implement a bare minimum
builtin `math` command. This is solely to ensure that fish can be built
and run in the Travis build environments. This is okay since anyone running
`builtin math` today is already getting an error response.
Also, more work is needed to support bare var references, multiple result
values, etc.
First step in fixing issue #3157 is to check-in the source code and hook
it into our build system.
The inclusion of the MuParser source adds the MIT License to those that
apply to fish. Update our documentation to reflect that fact.
The MuParser documentation is at
http://beltoforion.de/article.php?a=muparser. The source was downloaded
from https://github.com/beltoforion/muparser/releases. It is also hosted
on Github, https://github.com/beltoforion/muparser/. I did not download
it from Github because that source contained just a couple of cleanup
changes which don't affect its behavior.
Using a read-only variable like `status` as a for loop control variable
has never worked. But without this change you simply get non-sensical
behavior that leaves you scratching your head in puzzlement. This change
replaces the non-sensical behavior with an explicit error message.
Fixes#4342
Recent changes to switch to unordered sets/maps can cause the order in
which items are returned to be non-deterministic. This change ensures
that the argparse "Mutually exclusive flags" error message to be
deterministic with respect to the order of the interpolated values.
Make setting fish vars more efficient by avoiding creating a
wcstring_list_t for the case where we're setting one value. For the case
where we're passing a list of values swap it with the list in the var
rather than copying it. This makes the benchmark in #4200 approximately
6% faster.
Since we are including XXHash32/64 anyway for the wchar_t* hashing,
we might as well use it.
Use arch-specific hash size and xxhash for all wcstring hashing
Instead of using XXHash64 for all platforms, use the 32-bit version
when running on 32-bit platforms where XXHash64 is significantly slower
than XXHash32 (and the additional precision will not be used).
Additionally, manually specify wcstring_hash as hashing method for
non-const wcstring unordered_set/map instances (the const varieties
don't have an in-library hash and so already use our xxhash-based
specialization when calling std::hash<const wcstring>).
