Implement Add-PoshGitToProfile command

Utils.ps1

@@ -5,7 +5,8 @@ function Invoke-NullCoalescing {
     foreach($arg in $args) {
         if ($arg -is [ScriptBlock]) {
             $result = & $arg
-        } else {
+        }
+        else {
             $result = $arg
         }
         if ($result) { break }
@@ -26,6 +27,98 @@ function Invoke-Utf8ConsoleCommand ([ScriptBlock]$cmd) {
     }
 }
 
+function Add-ImportModuleToProfile {
+    param (
+        [Parameter(Position = 0, Mandatory = $true)]
+        [ValidateNotNullOrEmpty()]
+        [string]
+        $ProfilePath,
+
+        # This is only required to support PS v2 there $PSScriptRoot only works in a .psm1 file
+        [Parameter(Position = 1, Mandatory = $true)]
+        [ValidateNotNullOrEmpty()]
+        [string]
+        $ScriptRoot
+    )
+
+    # Check if profile script exists
+    if (Test-Path -LiteralPath $profilePath) {
+        $profileContent = @(Get-Content -LiteralPath $profilePath)
+        $profileContent += [string]::Empty # Empty line between previous profile script and import statement
+        $encoding = Get-FileEncoding $profilePath
+    }
+    else {
+        # Doesn't exist, so create it
+        New-Item -Path $profilePath -ItemType File
+        $profileContent = @()
+        $encoding = 'utf8'
+    }
+
+    # Check if the location of this module file is in the PSModulePath
+    if (Test-InModulePath $ScriptRoot) {
+        $profileContent += "Import-Module posh-git"
+    }
+    else {
+        $profileContent += "Import-Module '$ScriptRoot\posh-git.psd1'"
+    }
+
+    Set-Content -LiteralPath $profilePath -Value $profileContent -Encoding $encoding
+}
+
+<#
+.SYNOPSIS
+    Gets the file encoding of the specified file.
+.DESCRIPTION
+    Gets the file encoding of the specified file.
+.PARAMETER Path
+    Path to the file to check.  The file must exist.
+.EXAMPLE
+    PS C:\> Get-FileEncoding $profile
+    Get's the file encoding of the profile file.
+.INPUTS
+    None.
+.OUTPUTS
+    [System.String]
+.NOTES
+    Adapted from http://www.west-wind.com/Weblog/posts/197245.aspx
+#>
+function Get-FileEncoding($Path) {
+    $bytes = [byte[]](Get-Content $Path -Encoding byte -ReadCount 4 -TotalCount 4)
+
+    if (!$bytes) { return 'utf8' }
+
+    switch -regex ('{0:x2}{1:x2}{2:x2}{3:x2}' -f $bytes[0],$bytes[1],$bytes[2],$bytes[3]) {
+        '^efbbbf'   { return 'utf8' }
+        '^2b2f76'   { return 'utf7' }
+        '^fffe'     { return 'unicode' }
+        '^feff'     { return 'bigendianunicode' }
+        '^0000feff' { return 'utf32' }
+        default     { return 'ascii' }
+    }
+}
+
+<#
+.SYNOPSIS
+    Gets a StringComparison enum value appropriate for comparing paths on the OS platform.
+.DESCRIPTION
+    Gets a StringComparison enum value appropriate for comparing paths on the OS platform.
+.EXAMPLE
+    PS C:\> $pathStringComparison = Get-PathStringComparison
+.INPUTS
+    None
+.OUTPUTS
+    [System.StringComparison]
+#>
+function Get-PathStringComparison {
+    # File system paths are case-sensitive on Linux and case-insensitive on Windows and macOS
+    if (($PSVersionTable.PSVersion.Major -ge 6) -and $IsLinux) {
+        [System.StringComparison]::Ordinal
+    }
+    else {
+        [System.StringComparison]::OrdinalIgnoreCase
+    }
+}
+
 function Get-LocalOrParentPath($path) {
     $checkIn = Get-Item -Force .
     if ($checkIn.PSProvider.Name -ne 'FileSystem') {
@@ -35,15 +128,46 @@ function Get-LocalOrParentPath($path) {
         $pathToTest = [System.IO.Path]::Combine($checkIn.fullname, $path)
         if (Test-Path -LiteralPath $pathToTest) {
             return $pathToTest
-        } else {
+        }
+        else {
             $checkIn = $checkIn.parent
         }
     }
     return $null
 }
 
+function Test-InModulePath {
+    param (
+        [Parameter(Position=0, Mandatory=$true)]
+        [ValidateNotNull()]
+        [string]
+        $Path
+    )
+
+    $modulePaths = $env:PSModulePath -split ';'
+    if (!$modulePaths) { return $false }
+
+    $pathStringComparison = Get-PathStringComparison
+    $inModulePath = @($modulePaths | Where-Object { $Path.StartsWith($_, $pathStringComparison) }).Count -gt 0
+    $inModulePath
+}
+
+function Test-PoshGitImportedInScript {
+    param (
+        [Parameter(Position=0, Mandatory=$true)]
+        [string]
+        $Path
+    )
+
+    if (!$Path -or !(Test-Path -LiteralPath $Path)) {
+        return $false
+    }
+
+    @((Get-Content $Path -ErrorAction SilentlyContinue) -match 'posh-git').Count -gt 0
+}
+
 function dbg ($Message, [Diagnostics.Stopwatch]$Stopwatch) {
-    if($Stopwatch) {
+    if ($Stopwatch) {
         Write-Verbose ('{0:00000}:{1}' -f $Stopwatch.ElapsedMilliseconds,$Message) -Verbose # -ForegroundColor Yellow
     }
 }

install.ps1

@@ -1,5 +1,9 @@
 param([switch]$WhatIf = $false)
 
+# Dot source for Get-FileEncoding
+$scriptRoot = Split-Path $MyInvocation.MyCommand.Path -Parent
+. $scriptRoot\Utils.ps1
+
 if($PSVersionTable.PSVersion.Major -lt 2) {
     Write-Warning "posh-git requires PowerShell 2.0 or better; you have version $($Host.Version)."
     return
@@ -20,22 +24,6 @@ if(!(. (Join-Path $installDir "CheckVersion.ps1"))) {
     return
 }
 
-# Adapted from http://www.west-wind.com/Weblog/posts/197245.aspx
-function Get-FileEncoding($Path) {
-    $bytes = [byte[]](Get-Content $Path -Encoding byte -ReadCount 4 -TotalCount 4)
-
-    if(!$bytes) { return 'utf8' }
-
-    switch -regex ('{0:x2}{1:x2}{2:x2}{3:x2}' -f $bytes[0],$bytes[1],$bytes[2],$bytes[3]) {
-        '^efbbbf'   { return 'utf8' }
-        '^2b2f76'   { return 'utf7' }
-        '^fffe'     { return 'unicode' }
-        '^feff'     { return 'bigendianunicode' }
-        '^0000feff' { return 'utf32' }
-        default     { return 'ascii' }
-    }
-}
-
 $profileLine = ". '$installDir\profile.example.ps1'"
 if(Select-String -Path $PROFILE -Pattern $profileLine -Quiet -SimpleMatch) {
     Write-Host "It seems posh-git is already installed..."

posh-git.psm1

@@ -1,4 +1,4 @@
-param([switch]$NoVersionWarn)
+param([switch]$NoVersionWarn, [switch]$NoProfileCheck)
 
 if (Get-Module posh-git) { return }
 
@@ -38,7 +38,7 @@ $poshGitPromptScriptBlock = $null
 
 $currentPromptDef = if ($funcInfo = Get-Command prompt -ErrorAction SilentlyContinue) { $funcInfo.Definition }
 
-# HACK: If prompt is missing, create a global one we can overwrite with Set-Item
+# HACK: If prompt is missing, create a global one we can overwrite with Set-Item
 if (!$currentPromptDef) {
     function global:prompt { ' ' }
 }
@@ -92,6 +92,51 @@ if (!$currentPromptDef -or ($currentPromptDef -eq $defaultPromptDef)) {
     Set-Item Function:\prompt -Value $poshGitPromptScriptBlock
 }
 
+# IFF running interactive, check if user wants their profile script to be modified to import the module
+if (!$NoProfileCheck -and !$MyInvocation.ScriptName) {
+    # Search the user's profiles to see if any are using posh-git already
+    $importedInProfile = Test-PoshGitImportedInScript $PROFILE.CurrentUserCurrentHost
+    if (!$importedInProfile) {
+        $importedInProfile = Test-PoshGitImportedInScript $PROFILE.CurrentUserAllHosts
+    }
+    if (!$importedInProfile) {
+        $importedInProfile = Test-PoshGitImportedInScript $PROFILE.AllUsersCurrentHost
+    }
+    if (!$importedInProfile) {
+        $importedInProfile = Test-PoshGitImportedInScript $PROFILE.AllUsersAllHosts
+    }
+
+    # If we haven't detected that a profile script is using posh-git, ask if they want their profile modified to import posh-git
+    if (!$importedInProfile) {
+        $yesCurrent = New-Object System.Management.Automation.Host.ChoiceDescription -ArgumentList @(
+            "&Yes, for the current PowerShell host",
+            "Modify the profile for $($Host.Name) to automatically import posh-git."
+        )
+
+        $yesAll = New-Object System.Management.Automation.Host.ChoiceDescription -ArgumentList @(
+            "Yes, for &all PowerShell hosts",
+            "Modify the profile for all hosts to automatically import posh-git."
+        )
+
+        $no = New-Object System.Management.Automation.Host.ChoiceDescription -ArgumentList @(
+            "&No",
+            "Do not modify my profile. To suppress this prompt in the future, execute: Import-Module posh-git -Arg `$false, `$true"
+        )
+
+        $options = [System.Management.Automation.Host.ChoiceDescription[]]($yesCurrent, $yesAll, $no)
+
+        $title = "Modify Profile"
+        $message = "Do you want posh-git to modify your profile to automatically import this module whenever your start PowerShell?"
+        $result = $host.UI.PromptForChoice($title, $message, $options, 0)
+        switch ($result) {
+            0 { Add-ImportModuleToProfile $PROFILE.CurrentUserCurrentHost $PSScriptRoot }
+            1 { Add-ImportModuleToProfile $PROFILE.CurrentUserAllHosts $PSScriptRoot }
+            2 { } # Nothing to do if user picks 'No'
+            default { throw "Unexpected choice result: $result" }
+        }
+    }
+}
+
 # Install handler for removal/unload of the module
 $ExecutionContext.SessionState.Module.OnRemove = {
     $global:VcsPromptStatuses = $global:VcsPromptStatuses | Where-Object { $_ -ne $PoshGitVcsPrompt }

test/Utils.Tests.ps1

@@ -0,0 +1,104 @@
+. $PSScriptRoot\..\Utils.ps1
+
+Describe 'Utils Function Tests' {
+    Context 'Add-ImportModuleToProfile Tests' {
+        BeforeAll {
+           $newLine = [System.Environment]::NewLine
+        }
+        BeforeEach {
+            $profilePath = [System.IO.Path]::GetTempFileName()
+        }
+        AfterEach {
+            Remove-Item $profilePath -ErrorAction SilentlyContinue
+        }
+        It 'Creates profile file if it does not exist' {
+            Remove-Item -LiteralPath $profilePath
+            Test-Path -LiteralPath $profilePath | Should Be $false
+            $scriptRoot = Split-Path $profilePath -Parent
+            Add-ImportModuleToProfile $profilePath $scriptRoot
+            Test-Path -LiteralPath $profilePath | Should Be $true
+            Get-FileEncoding $profilePath | Should Be 'utf8'
+            $content = Get-Content $profilePath
+            $content.Count | Should Be 1
+            @($content)[0] | Should BeExactly "Import-Module '$scriptRoot\posh-git.psd1'"
+        }
+        It 'Modifies existing (Unicode) profile file correctly' {
+            $profileContent = @'
+Import-Module PSCX
+
+New-Alias pscore C:\Users\Keith\GitHub\rkeithhill\PowerShell\src\powershell-win-core\bin\Debug\netcoreapp1.1\win10-x64\powershell.exe
+'@
+            Set-Content $profilePath -Value $profileContent -Encoding Unicode
+            $scriptRoot = Split-Path $profilePath -Parent
+            Add-ImportModuleToProfile $profilePath $scriptRoot
+            Test-Path -LiteralPath $profilePath | Should Be $true
+            Get-FileEncoding $profilePath | Should Be 'unicode'
+            $content = Get-Content $profilePath
+            $content.Count | Should Be 5
+            $profileContent += "${newLine}${newLine}Import-Module '$scriptRoot\posh-git.psd1'"
+            $content -join $newLine | Should BeExactly $profileContent
+        }
+    }
+
+    Context 'Test-PoshGitImportedInScript Tests' {
+        BeforeEach {
+            $profilePath = [System.IO.Path]::GetTempFileName()
+        }
+        AfterEach {
+            Remove-Item $profilePath -ErrorAction SilentlyContinue
+        }
+        It 'Detects Import-Module posh-git in profile script' {
+            $profileContent = "Import-Module posh-git"
+            Set-Content $profilePath -Value $profileContent -Encoding Unicode
+            Test-PoshGitImportedInScript $profilePath | Should Be $true
+        }
+        It 'Detects chocolatey installed line in profile script' {
+            $profileContent = ". 'C:\tools\poshgit\dahlbyk-posh-git-18d600a\profile.example.ps1"
+            Set-Content $profilePath -Value $profileContent -Encoding Unicode
+            Test-PoshGitImportedInScript $profilePath | Should Be $true
+        }
+        It 'Returns false when profile script does not import posh-git' {
+            $profileContent = "Import-Module Pscx`nImport-Module platyPS`nImport-Module Plaster"
+            Set-Content $profilePath -Value $profileContent -Encoding Unicode
+            Test-PoshGitImportedInScript $profilePath | Should Be $false
+        }
+    }
+
+    Context 'Test-InModulePath Tests' {
+        BeforeAll {
+            $standardPSModulePath = "C:\Users\Keith\Documents\WindowsPowerShell\Modules;C:\Program Files\WindowsPowerShell\Modules;C:\WINDOWS\system32\WindowsPowerShell\v1.0\Modules\"
+        }
+        BeforeEach {
+            $origPSModulePath = $env:PSModulePath
+        }
+        AfterEach {
+            $env:PSModulePath = $origPSModulePath
+        }
+        It 'Works for install from PSGallery to current user modules location' {
+            $env:PSModulePath = $standardPSModulePath
+            $path = "C:\Users\Keith\Documents\WindowsPowerShell\Modules\posh-git\0.7.0"
+            Test-InModulePath $path | Should Be $true
+        }
+        It 'Works for install from Chocolatey not in any modules path' {
+            $env:PSModulePath = $standardPSModulePath
+            $path = "C:\tools\posh-git\dahlbyk-posh-git-18d600a"
+            Test-InModulePath $path | Should Be $false
+        }
+        It 'Works for running from posh-git Git repo and location not in modules path' {
+            $env:PSModulePath = $standardPSModulePath
+            $path = "C:\Users\Keith\GitHub\posh-git"
+            Test-InModulePath $path | Should Be $false
+        }
+        It 'Returns false when PSModulePath is empty' {
+            $env:PSModulePath = ''
+            $path = "C:\Users\Keith\Documents\WindowsPowerShell\Modules\posh-git\0.7.0"
+            Test-InModulePath $path | Should Be $false
+        }
+        It 'Returns false when PSModulePath is missing' {
+            Remove-Item Env:\PSModulePath
+            Test-Path Env:\PSModulePath | Should Be $false
+            $path = "C:\Users\Keith\Documents\WindowsPowerShell\Modules\posh-git\0.7.0"
+            Test-InModulePath $path | Should Be $false
+        }
+    }
+}

test/testDebugHarness.ps1

@@ -0,0 +1,2 @@
+
+Invoke-Pester $PSScriptRoot\Utils.Tests.ps1