Fix powershell script for non-windows users

README.md

@@ -46,6 +46,14 @@ Make sure to source `jabba.sh` in your environment if you skip it:
 ```sh
 [ -s "$JABBA_HOME/jabba.sh" ] && source "$JABBA_HOME/jabba.sh"
 ```
+> (in powershell)
+
+```powershell
+[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
+Invoke-Expression (
+  Invoke-WebRequest https://github.com/shyiko/jabba/raw/master/install.ps1 -UseBasicParsing
+).Content
+```
 
 > In [fish](https://fishshell.com/) command looks a little bit different - 
 `curl -sL https://github.com/shyiko/jabba/raw/master/install.sh | bash; and . ~/.jabba/jabba.fish` 

install.ps1

@@ -1,7 +1,25 @@
 $ErrorActionPreference = "Stop"
 
-$jabbaHome = if ($env:JABBA_HOME) { $env:JABBA_HOME } else { if ($env:JABBA_DIR) { $env:JABBA_DIR } else { "$env:USERPROFILE\.jabba" } }
+$sep = [IO.Path]::DirectorySeparatorChar
+$jabbaHome = if ($env:JABBA_HOME) { 
+    $env:JABBA_HOME 
+} else { 
+    if ($env:JABBA_DIR) { 
+        $env:JABBA_DIR 
+    } else {
+        if($env:USERPROFILE){
+            "$env:USERPROFILE" + $sep + ".jabba" 
+        }else{
+            "$env:HOME" + $sep + ".jabba"
+        }
+    } 
+}
 $jabbaVersion = if ($env:JABBA_VERSION) { $env:JABBA_VERSION } else { "latest" }
+# The Windows values of the Platform enum are:
+# 0 (Win32NT), 1 (Win32S), 2 (Win32Windows) and 3 (WinCE).
+# Other values are larger and indicate non Windows operating systems
+$isOnWindows = [System.Environment]::OSVersion.Platform.value__ > 3
+$jabbaExecutableName = $isOnWindows ? "jabba.exe" : "jabba"
 
 if ($jabbaVersion -eq "latest")
 {
@@ -25,17 +43,35 @@ if ($env:JABBA_MAKE_INSTALL -eq "true")
 }
 else
 {
-    Invoke-WebRequest https://github.com/shyiko/jabba/releases/download/$jabbaVersion/jabba-$jabbaVersion-windows-amd64.exe -UseBasicParsing -OutFile $jabbaHome/bin/jabba.exe
+    # $isOnWindows, see top of the file
+    # macOS enum value: 6
+    # Unix enum value: 4
+    if($isOnWindows){
+        Invoke-WebRequest https://github.com/shyiko/jabba/releases/download/$jabbaVersion/jabba-$jabbaVersion-windows-amd64.exe -UseBasicParsing -OutFile $jabbaHome/bin/$jabbaExecutableName
+    }
+    elseif([System.Environment]::OSVersion.Platform.value__ -eq 4 || [System.Environment]::OSVersion.Platform.value__ -eq 6){
+        Invoke-WebRequest https://github.com/shyiko/jabba/releases/download/$jabbaVersion/jabba-$jabbaVersion-darwin-amd64 -UseBasicParsing -OutFile $jabbaHome/bin/$jabbaExecutableName
+    }else{
+        $osArch = [System.Environment]::Is64BitOperatingSystem ? "amd64" : "386"
+        Invoke-WebRequest https://github.com/shyiko/jabba/releases/download/$jabbaVersion/jabba-$jabbaVersion-linux-${OSARCH} -UseBasicParsing -OutFile $jabbaHome/bin/$jabbaExecutableName
+    }
 }
 
 $ErrorActionPreference="SilentlyContinue"
-& $jabbaHome\bin\jabba.exe --version | Out-Null
+
+if($isOnWindows){
+    & "$jabbaHome\bin\$jabbaExecutableName" --version | Out-Null
+}else{
+	chmod a+x "$jabbaHome/bin/$jabbaExecutableName"
+    & "$jabbaHome/bin/$jabbaExecutableName" --version | Out-Null
+}
+
 $binaryValid = $?
 $ErrorActionPreference="Continue"
 if (-not $binaryValid)
 {
-    Write-Host @"
-$jabbaHome\bin\jabba does not appear to be a valid binary.
+    Write-Host -ForegroundColor Yellow @"
+$jabbaHome\bin\$jabbaExecutableName does not appear to be a valid binary.
 
 Check your Internet connection / proxy settings and try again.
 if the problem persists - please create a ticket at https://github.com/shyiko/jabba/issues.
@@ -49,7 +85,7 @@ if the problem persists - please create a ticket at https://github.com/shyiko/ja
 function jabba
 {
     `$fd3=`$([System.IO.Path]::GetTempFileName())
-    `$command="& '$jabbaHome\bin\jabba.exe' `$args --fd3 ```"`$fd3```""
+    `$command="& '$jabbaHome\bin\$jabbaExecutableName' `$args --fd3 ```"`$fd3```""
     & { `$env:JABBA_SHELL_INTEGRATION="ON"; Invoke-Expression `$command }
     `$fd3content=`$(Get-Content `$fd3)
     if (`$fd3content) {
@@ -81,6 +117,6 @@ else
 
 Write-Host @"
 
-Installation completed
+Installation completed (you might need to restart your terminal for the jabba command to be available)
 (if you have any problems please report them at https://github.com/shyiko/jabba/issues)
 "@