* Revert "History, more test coverage improvements, and refactorings. (#3217)"
This reverts commit 8fc8fc89aa.
* Add tests
* Refactor .nu-env
* Change logic of Config write to logic of read()
* Fix reload always appends to old vars
* Fix reload always takes last_modified of global config
* Add reload_config in evaluation context
* Reload config after writing to it in cfg set / cfg set_into
* Add --no-history to cli options
* Use --no-history in tests
* Add comment about maybe_print_errors
* Get ctrl_exit var from context.global_config
* Use context.global_config in command "config"
* Add Readme in engine how env vars are now handled
* Update docs from autoenv command
* Move history_path from engine to nu_data
* Move load history out of if
* No let before return
* Add import for indexmap
* update docs to refer to length instead of count
* rename count to length
* change all occurrences of 'count' to 'length' in tests
* format length command
The autoenv logic mutates environment variables in the running session as
it operates and decides what to do for trusted directories containing `.nu-env`
files. Few of the ways to interact with it were all in a single test function.
We separate out all the ways that were done in the single test function to document
it better. This will greatly help once we start refactoring our way out from setting
environment variables this way to just setting them to `Scope`.
This is part of an on-going effort to keep variables (`PATH` and `ENV`)
in our `Scope` and rely on it for everything related to variables.
We expect to move away from setting (`std::*`) envrironment variables in the current
running process. This is non-trivial since we need to handle cases from vars
coming in from the outside world, prioritize, and also compare to the ones
we have both stored in memory and in configuration files.
Also to send out our in-memory (in `Scope`) variables properly to external
programs once we no longer rely on `std::env` vars from the running process.
