panache-git: do not print stderr from Git commands (nushell#813)

Nushell 0.92 changed how external commands operate in pipelines:
https://www.nushell.sh/blog/2024-04-02-nushell_0_92_0.html

After updating to Nushell 0.92, panache-git would print errors when the
current working directory was not a Git repository: "fatal: not a git
repository (or any of the parent directories): .git"

This change properly handles stderr from Git commands according to
Nushell's updated external command behavior.

Also, Nushell 0.91 introduced "is-not-empty", so places in the code
where a string was checked for being not-empty or not-contains were
simplified a bit.

Finally, the main command in the module was renamed to "main" to make it
simpler to import and use in config.

modules/prompt/panache-git.nu

@@ -4,20 +4,20 @@
 # Quick Start:
 # - Download this file (panache-git.nu)
 # - In your Nushell config:
-# - Import the panache-git command from the panache-git.nu module file
+# - Import the main command from the panache-git.nu module file
 # - Set panache-git as your prompt command
 # - Disable the separate prompt indicator by setting it to an empty string
 # - For example, with this file in your home directory:
-# use ~/panache-git.nu panache-git
-# $env.PROMPT_COMMAND = { panache-git }
-# $env.PROMPT_INDICATOR = { "" }
+# use ~/panache-git.nu main
+# $env.PROMPT_COMMAND = {|| panache-git }
+# $env.PROMPT_INDICATOR = {|| "" }
 # - Restart Nushell
 #
 # For more documentation or to file an issue, see https://github.com/ehdevries/panache-git
 
 
 # An opinionated Git prompt for Nushell, styled after posh-git
-export def prompt-with-panache [] {
+export def main [] {
  let prompt = ($'(current-dir) (repo-styled)' | str trim)
  $'($prompt)> '
 }
@@ -30,7 +30,7 @@ export def current-dir [] {
  do --ignore-errors { $current_dir | path relative-to $nu.home-path } | str join
  )
 
- let in_sub_dir_of_home = ($current_dir_relative_to_home | is-empty | nope)
+ let in_sub_dir_of_home = ($current_dir_relative_to_home | is-not-empty)
 
  let current_dir_abbreviated = (if $in_sub_dir_of_home {
  $'~(char separator)($current_dir_relative_to_home)' | str replace -ar '\\' '/'
@@ -43,7 +43,7 @@ export def current-dir [] {
 
 # Get repository status as structured data
 export def repo-structured [] {
- let in_git_repo = (do --ignore-errors { git rev-parse --abbrev-ref HEAD } | is-empty | nope)
+ let in_git_repo = (do { git rev-parse --abbrev-ref HEAD } | complete | get stdout | is-not-empty)
 
  let status = (if $in_git_repo {
  git --no-optional-locks status --porcelain=2 --branch | lines
@@ -55,8 +55,7 @@ export def repo-structured [] {
  $status
  | where ($it | str starts-with '# branch.head')
  | first
- | str contains '(detached)'
- | nope
+ | str contains --not '(detached)'
  } else {
  false
  })
@@ -86,8 +85,7 @@ export def repo-structured [] {
  $status
  | where ($it | str starts-with '# branch.upstream')
  | str join
- | is-empty
- | nope
+ | is-not-empty
  } else {
  false
  })
@@ -96,8 +94,7 @@ export def repo-structured [] {
  $status
  | where ($it | str starts-with '# branch.ab')
  | str join
- | is-empty
- | nope
+ | is-not-empty
  } else {
  false
  })
@@ -133,8 +130,7 @@ export def repo-structured [] {
  $status
  | where ($it | str starts-with '1') or ($it | str starts-with '2')
  | str join
- | is-empty
- | nope
+ | is-not-empty
  } else {
  false
  })
@@ -143,8 +139,7 @@ export def repo-structured [] {
  $status
  | where ($it | str starts-with '?')
  | str join
- | is-empty
- | nope
+ | is-not-empty
  } else {
  false
  })
@@ -153,8 +148,7 @@ export def repo-structured [] {
  $status
  | where ($it | str starts-with 'u')
  | str join
- | is-empty
- | nope
+ | is-not-empty
  } else {
  false
  })
@@ -380,10 +374,6 @@ export def repo-styled [] {
 
 # Helper commands to encapsulate style and make everything else more readable
 
-def nope [] {
- each { |it| $it == false }
-}
-
 def bright-cyan [] {
  each { |it| $"(ansi -e '96m')($it)(ansi reset)" }
 }