When setting a variable without a specified scope, we should give priority
to an existing local or global above an existing universal variable with
the same name.
In 16fd780484 there was a regression that
made universal variables have priority.
Fixes#5883
Prior to this fix, a function_block stored a process_t, which was only used
when printing backtraces. Switch this to an array of arguments, and make
various other cleanups around null terminated argument arrays.
This runs build_tools/style.fish, which runs clang-format on C++, fish_indent on fish and (new) black on python.
If anything is wrong with the formatting, we should fix the tools, but automated formatting is worth it.
This was a sort of side channel that was only used to propagate redraws
after universal variable changes. We can eliminate it and handle these
more directly.
env_scoped_t lives between environment_t and env_stack_t.
It represents the read-only logic of env_stack_t and will be used to back
the new environment snapshot implementation.
Prior to this change, fish used a global flag to decide if we should check
for changes to universal variables. This flag was then checked at arbitrary
locations, potentially triggering variable updates and event handlers for
those updates; this was very hard to reason about.
Switch to triggering a universal variable update at a fixed location,
after running an external command. The common case is that the variable
file has not changed, which we can identify with just a stat() call, so
this is pretty cheap.
When popping a scope from the environment stack, we currently do a lot of
nonsense like looking for changed curses variables. We want to centralize
this in env_stack_t so that it can be migrated to the env_dispatch logic.
Move this logic up one level in preparation for doing that.
This new file is supposed to encapsulate all of the logic around
reacting to variable changes, as opposed to the environment core.
This is to help break up the env.cpp monolith.
This switches env_var_t to be an immutable value type, and stores its
contents via a shared_ptr. This eliminates string copying when fetching
env_var_t values.
