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.
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.
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.
No longer using RAII wrappers around pthread_mutex_t and pthread_cond_t
in favor of the C++11 std::mutex, std::recursive_mutex, and
std::condition_variable data types.
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.
It's bugged me forever that the scope is the second arg to `env_get()`
but not `env_set()`. And since I'll be introducing some helper functions
that wrap `env_set()` now is a good time to change the order of its
arguments.
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
Fish 2.6.0 introduced a regression that keeps setting
`fish_escape_delay_ms` as a uvar from working. This also fixes a related
problem: callbacks generated from the initial loading of universal vars
were not being acted on.
Fixes#4196
This fixes a stupid bug in my previous commit to standardize on a new
`list_to_array_val()` function. This adds a unit test to keep this from
regressing.
This is the first step in implementing a better abstraction for handling
fish script vars in the C++ code. It implements a new function (with two
signatures) to provide a standard method for construct the flag string
representation of a fish script array.
Partial fix for #4200
This implements `status is-breakpoint` that returns true if the current
shell prompt is displayed in the context of a `breakpoint` command.
This also fixes several bugs. Most notably making `breakpoint` a no-op if
the shell isn't interactive. Also, typing `breakpoint` at an interactive
prompt should be an error rather than creating a new nested debugging
context.
Partial fix for #1310
This started out as a refactoring to eliminate the lint warnings. Adding
unit tests revealed the current implementation does not behave as
implied. So this is a complete rewrite of the implementation. With the
addition of unit tests so that it doesn't break in the future and anyone
who thinks this new version behaves wrong can update the unit tests to
help ensure we're testing for the correct behavior.
Fixes#4027
This changes all of the builtins to behave like `string` to return
STATUS_INVALID_ARGS (121) if the args passed to the command don't make
sense. Also change several of the builtins to use the existing symbols
(e.g., STATUS_CMD_OK and STATUS_CMD_ERROR) rather than hardcoded "0"
and "1" for consistency and to make it easier to find such values in
the future.
Fixes#3985
This primarily replaces "STATUS_BUILTIN_OK" with "STATUS_CMD_OK" and
"STATUS_BUILTIN_ERROR" with "STATUS_CMD_ERROR". That is because we want
to make it clear these status codes are applicable to fish functions as
well as builtins. Future changes will make it easier to use these
symbols and values in functions.
There should be just one place that calls `setupterm()`. While refactoring
the code I also decided to not make initializing the curses subsystem a
fatal error. We now try two fallback terminal names ("ansi" and "dumb")
and if those can't be used we still end up with a usable shell.
Fixes#3850
I recently upgraded the software on my macOS server and was dismayed to
see that cppcheck reported a huge number of format string errors due to
mismatches between the format string and its arguments from calls to
`assert()`. It turns out they are due to the macOS header using `%lu`
for the line number which is obviously wrong since it is using the C
preprocessor `__LINE__` symbol which evaluates to a signed int.
I also noticed that the macOS implementation writes to stdout, rather
than stderr. It also uses `printf()` which can be a problem on some
platforms if the stream is already in wide mode which is the normal case
for fish.
So implement our own `assert()` implementation. This also eliminates
double-negative warnings that we get from some of our calls to
`assert()` on some platforms by oclint.
Also reimplement the `DIE()` macro in terms of our internal
implementation.
Rewrite `assert(0 && msg)` statements to `DIE(msg)` for clarity and to
eliminate oclint warnings about constant expressions.
Fixes#3276, albeit not in the fashion I originally envisioned.
We now are stingier with taking history file locks - if the lock
is held too long we may just break it. But the current file save
architecture holds the lock for the duration of the save. It also
has some not-quite-right checks that can cause spurious failures in
the history stress test.
Reimplement the history save to retry. Rather than holding the lock,
rewrite the file to a temporary location and then take the lock. If
the history file has changed, start all over.
This is going to be slower under contention, but the advantage is that
the lock is only held for a brief period (stat + rename) rather than
across calls to write().
Some updated logic also fixes spurious failures that were easy to observe
when tsan was enabled. These failures were due to failing to check if the
file at the path was the same file we opened.
The next step is to move the history file saving to a background thread
to reduce the chances of it impacting user's typing.
Commit ab189a75 introduced a regression where we stop breaking out
of loops in response to a child death via a signal. Fix that regression.
Also introduces a test to help ensure we don't regress in the future.
Fixes#3780
Previously we would try to walk all the blocks (from within the
signal handler!) and mark them as skipped. Stop doing that, it's
wildly unsafe.
Also rationalize how the skip flag is set per block. Remove places
that shouldn't set it (e.g. break and continue shouldn't set skip
on the loop block).
We should never use stdio functions that use stdout implicitly. Saving a
few characters isn't worth the inconsistency. Too, using the forms such
as `fwprintf()` which take an explicit stream makes it easier to find
the places we write to stdout versus stderr.
Fixes#3728
