编辑命令行提示符 prompt，支持显示 git 分支、标签等信息

实时在
Linhieng/current–Microsoft.PowerShell_profile.ps1 上更新

打开 $Profile 文件，将下面内容粘贴到其中即可：

<# 负责打印 git 分支相关信息支持输出以下信息：当前分支，或者是 hash 值当前目录是否为 git 子目录当前是否有提交历史
#>
function write_host_git_branch {# 在这里，能确保是一个 git 仓库，或者是一个 git 仓库中的子目录# 获取当前 HEAD 所在分支名。如果当前是 detached HEAD 状态，则显示为 hash。$git_branch = git symbolic-ref --short --quiet HEADWrite-Host "(" -ForegroundColor "DarkGray" -NoNewlineif ( $null -eq $git_branch ) {$hash = git rev-parse --short HEADWrite-Host $hash -ForegroundColor "red" -NoNewline} else {Write-Host $git_branch -ForegroundColor "blue" -NoNewline}Write-Host ") " -ForegroundColor "DarkGray" -NoNewlineif (# 如果当前目录没有 .git 文件夹，说明当前是在 git 仓库的子目录$false -eq (Test-Path .git)) {Write-Host "sub " -ForegroundColor "DarkGray" -NoNewline}$git_log = git log 2>&1if (# 命令执行失败$? -eq $false) {write_host_not_commits($git_log)}$tags = git tag --points-at HEADif ($null -ne $tags) {$tags_one_line =  ($tags -split '\r?\n') -join ', 'Write-Host "[" -ForegroundColor "DarkGray" -NoNewlineWrite-Host "$tags_one_line" -ForegroundColor "DarkYellow" -NoNewlineWrite-Host "] " -ForegroundColor "DarkGray" -NoNewline}# 打印子模块相关信息会有性能问题# $submodule = git submodule status 2>&1
}function write_host_not_commits($git_log) {$error_message = ($git_log.Exception.Message | Select-Object -First 1).Trim()if ($true -eq $error_message.EndsWith("does not have any commits yet")) {Write-Host "not commits yet"  -ForegroundColor "red" -NoNewline} else {Write-Host "❌fatal: $error_message" -ForegroundColor "red" -NoNewline}return
}function wirte_host_git_wrong($git_output) {# 转换为字符串对象，并只获取第一行的内容$error_message = ($git_output.Exception.Message | Select-Object -First 1).Trim()# 检查输出是否以指定的前缀开头if (# 空（非 git 仓库）$true -eq $error_message.StartsWith("fatal: not a git repository")) {Write-Host "" -NoNewline} elseif (# 不安全的仓库$true -eq $error_message.StartsWith("fatal: detected dubious ownership")) {Write-Host "❌fatal: detected dubious ownership" -ForegroundColor "red" -NoNewline} else {Write-Host "❌fatal: $error_message" -ForegroundColor "red" -NoNewline}
}function write_host_git_info {# 执行 Git 命令并捕获输出。 2>&1 表示将 stderr 重定向到 stdout, 以将错误信息保存在 $git_output 变量中$git_output = git rev-parse --is-inside-work-tree 2>&1if (# 前一个命令执行失败$? -eq $false) {wirte_host_git_wrong($git_output)return}write_host_git_branch
}# 判断当前是否是管理员
function has_admin_power {$identity = [Security.Principal.WindowsIdentity]::GetCurrent()$principal = [Security.Principal.WindowsPrincipal] $identity$adminRole = [Security.Principal.WindowsBuiltInRole]::Administratorreturn $principal.IsInRole($adminRole)
}function __prompt {# 空格原则：输出内容时，不需要考虑给前面留空，只需要考虑给后面留空$pwsh_version = "PS$($Host.version.Major) "$fullpath = "$($executionContext.SessionState.Path.CurrentLocation)"Write-Host "`n$pwsh_version" -NoNewlineWrite-Host "$fullpath " -NoNewline -ForegroundColor "green"write_host_git_infoif (has_admin_power) {return "`n# "} else {return "`n$ "}}# 主入口
function prompt {# 编写的代码可能报错try {__promptreturn} catch {# 输出报错信息Write-Host "powershell script error occurred: $_" -NoNewline -ForegroundColor "red"}return "`nPS> "
}# 解决终端的中文乱码问题。注意，chcp 无效！
$OutputEncoding = [console]::InputEncoding = [console]::OutputEncoding = New-Object System.Text.UTF8Encoding
# 设置 UpArrow 快捷方式为向前搜索
Set-PSReadLineKeyHandler -Key UpArrow -ScriptBlock {[Microsoft.PowerShell.PSConsoleReadLine]::HistorySearchBackward()[Microsoft.PowerShell.PSConsoleReadLine]::EndOfLine()
} # 设置向上键为后向搜索历史记录
# 设置 DownArrow 快捷方式为向后搜索
Set-PSReadLineKeyHandler -Key DownArrow -ScriptBlock {[Microsoft.PowerShell.PSConsoleReadLine]::HistorySearchForward()[Microsoft.PowerShell.PSConsoleReadLine]::EndOfLine()
}