Describe the bug

1. When starting with nu --no-config-file/-n:

   • the Nushell defaults for $env.config are not populated into the environment. The defaults are still in play if they haven't been overwritten by a corresponding variable in the environment, but they cannot be introspected by the user with, e.g., $env.config.color_config.
   • $env.NU_LIB_DIRS is populated with a default, even if it was not present in the parent process
   • $env.PROMPT_ variables are not populated by default, but may be inherited from the parent process.

2. When starting with an empty or user-generated config.nu or env.nu the default config values are also not populated into the environment. Same rules as above apply.

3. However, when starting nu when no env.nu and/or config.nu exists, Nushell will ask the user if they want to create one. If the user responds with "n"/No, then there is no file, but $env.config is fully populated with the defaults (when there is no config.nu), as are $env.PROMPT_* variables when there is no env.nu.

How to reproduce

Best to run all of these from a parent Bash process where there are no Nushell environment variables set. For Windows users, WSL makes this pretty easy by starting with wsl ~ -e /usr/bin/bash.

1. Scenario 1 above

   nu -n
   $env.config
   # => Result
   $env.config                                                                                                                                                                                                                 
   08/22/2024 09:34:23 AM
   Error: nu::shell::column_not_found
   
     × Cannot find column 'config'
      ╭─[entry #1:1:1]
    1 │ $env.config
      · ──┬─ ───┬──
      ·   │     ╰── cannot find column 'config'
      ·   ╰── value originates here
      ╰────
   
   $env.NU_LIB_DIRS
   # => Result
   ╭───┬────────────────────────────────────────────╮
   │ 0 │ /home/ntd/.config/nushell/scripts          │
   │ 1 │ /home/ntd/.local/share/nushell/completions │
   ╰───┴────────────────────────────────────────────╯
   

2. Scenario 2 above:

   Important: Run through Scenario 3 to start, but don't exit Nushell when finished.

   touch ($nu.default-config-dir | path join "config.nu")
   # Exit Nushell, don't exit Bash so that the XDG_CONFIG_HOME is still in play
   nu
   # Get prompt only for env.nu - Say "no"
   $env.config.color_config.block 
   # => Result
   Error: nu::shell::column_not_found
   
     × Cannot find column 'config'
      ╭─[entry #1:1:1]
    1 │ $env.config.color_config.block
      · ──┬─ ───┬──
      ·   │     ╰── cannot find column 'config'
      ·   ╰── value originates here
      ╰────
   
   # default_env.nu is still in play
   view source ($env.PROMPT_COMMAND)
   # => {|| create_left_prompt }

3. Scenario 3 above:

   # from bash
   export XDG_CONFIG_HOME=$(mktemp -d)
   nu
   # Say n to both prompts
   $env.config.color_config.block
   # => white
   view source ($env.PROMPT_COMMAND)
   # => {|| create_left_prompt }
   view source create_left_prompt
   # => Prompt function is defined
   view files | find default
   # =>
   ╭───┬───────────────────┬───────┬────────┬───────╮
   │ # │     filename      │ start │  end   │ size  │
   ├───┼───────────────────┼───────┼────────┼───────┤
   │ 0 │ default_env.nu    │ 85633 │  89910 │  4277 │
   │ 1 │ default_config.nu │ 89967 │ 119773 │ 29806 │
   ╰───┴───────────────────┴───────┴────────┴───────╯

Expected behavior

My ideal scenario is more of an enhancement request that I'll open separately, but I would expect more consistency in the way that default_config.nu and default_env.nu are loaded.

Screenshots

No response

Configuration

Additional context

No response