Address feedback to install.ps1

scripts/obtain/install.ps1

@@ -3,22 +3,59 @@
 # Licensed under the MIT license. See LICENSE file in the project root for full license information.
 #
 
+<#
+.SYNOPSIS
+    Installs dotnet cli
+.DESCRIPTION
+    Installs dotnet cli. If dotnet installation already exists in the given directory
+    it will update it only if the requested version differs from the one already installed.
+.PARAMETER Channel
+    Channel is the way of reasoning about stability and quality of dotnet. This parameter takes one of the values:
+    - nightly - Possibly unstable, frequently changing
+    - preview - Pre-release stable with known issues and feature gaps
+    - production - Most stable releases
+.PARAMETER Version
+    Represents a build version on specific channel. Possible values:
+    - 4-part version in a format A.B.C.D - represents specific version of build
+    - latest - most latest build on specific channel
+    - lkg - last known good version on specific channel
+.PARAMETER InstallDir
+    Path to where to install dotnet. Note that binaries will be placed directly in a given directory.
+    Defaults to %LocalAppData%\Microsoft\.dotnet
+.PARAMETER Architecture
+    Architecture of dotnet binaries to be installed. Defaults to the OS architecture.
+    Possible values are: AMD64 and x86
+.PARAMETER DebugSymbols
+    If set the installer will include symbols in the installation.
+.PARAMETER DryRun
+    If set it will not perform installation but instead display what command line to use to consistently install
+    currently requested version of dotnet cli. In example if you specify version 'latest' it will display a link
+    with specific version so that this command can be used deterministicly in a build script.
+    It also displays binaries location if you prefer to install or download it yourself.
+.PARAMETER NoPath
+    By default this script will set environment variable PATH for the current process to the binaries folder inside installation folder.
+    If set it will display binaries location but not set any environment variable.
+.PARAMETER Verbose
+    Displays diagnostics information.
+.PARAMETER AzureFeed
+    This parameter should not be usually changed by user. It allows to change URL for the Azure feed used by this installer.
+#>
 [cmdletbinding()]
 param(
    [string]$Channel="nightly",
    [string]$Version="Latest",
    [string]$InstallDir="<usershare>",
    [string]$Architecture="auto",
+   [switch]$DebugSymbols, # TODO: Switch does not work yet. Symbols zip is not being uploaded yet.
    [switch]$DryRun,
-   [bool]$DebugSymbols=$false, # TODO: There is no zip uploaded yet
-   [bool]$NoPath=$false
+   [switch]$NoPath,
+   [string]$AzureFeed="https://dotnetcli.blob.core.windows.net/dotnet"
 )
 
 Set-StrictMode -Version Latest
 $ErrorActionPreference="Stop"
 $ProgressPreference="SilentlyContinue"
 
-$AzureFeed="https://dotnetcli.blob.core.windows.net/dotnet"
 $LocalVersionFileRelativePath="\.version"
 $BinFolderRelativePath="\bin"
 
@@ -49,7 +86,7 @@ function Get-CLIArchitecture-From-Architecture([string]$Architecture) {
 
     switch ($Architecture.ToLower()) {
         { $_ -eq "auto" } { return Get-CLIArchitecture-From-Architecture $(Get-Machine-Architecture) }
-        { ($_ -eq "amd64") -Or ($_ -eq "x64") } { return "x64" }
+        { ($_ -eq "amd64") -or ($_ -eq "x64") } { return "x64" }
         { $_ -eq "x86" } { return "x86" }
         default { throw "Architecture not supported. If you think this is a bug, please report it at https://github.com/dotnet/cli/issues" }
     }
@@ -82,9 +119,10 @@ function Get-Latest-Version-Info([string]$AzureFeed, [string]$AzureChannel, [str
 function Get-Azure-Channel-From-Channel([string]$Channel) {
     Say-Invocation $MyInvocation
 
+    # For compatibility with build scripts accept also directly Azure channels names
     switch ($Channel.ToLower()) {
-        { $_ -eq "nightly" } { return "dev" }
-        { $_ -eq "preview" } { return "beta" }
+        { ($_ -eq "nightly") -or ($_ -eq "dev") } { return "dev" }
+        { ($_ -eq "preview") -or ($_ -eq "beta") } { return "beta" }
         { $_ -eq "production" } { throw "Production channel does not exist yet" }
         default { throw "``$Channel`` is an invalid channel name. Use one of the following: ``nightly``, ``preview``, ``production``" }
     }
@@ -134,7 +172,7 @@ function Resolve-Installation-Path([string]$InstallDir) {
 function Get-Installed-Version-Info([string]$InstallRoot) {
     Say-Invocation $MyInvocation
 
-    $VersionFile = $InstallRoot + $LocalVersionFileRelativePath
+    $VersionFile = Join-Path -Path $InstallRoot -ChildPath $LocalVersionFileRelativePath
     Say-Verbose "Local version file: $VersionFile"
     
     if (Test-Path $VersionFile) {
@@ -212,10 +250,13 @@ Extract-And-Override-Zip -ZipPath $ZipPath -OutPath $InstallRoot
 Say "Removing installation artifacts"
 Remove-Item $ZipPath
 
+$BinPath = Get-Absolute-Path $(Join-Path -Path $InstallRoot -ChildPath $BinFolderRelativePath)
 if (-Not $NoPath) {
-    $BinPath = Get-Absolute-Path $(Join-Path -Path $InstallRoot -ChildPath $BinFolderRelativePath)
-    Say "Adding to PATH: `"$BinPath`""
+    Say "Adding to current process PATH: `"$BinPath`". Note: This change will not be visible if PowerShell was run as a child process."
     $env:path += ";$BinPath"
 }
+else {
+    Say "Binaries of dotnet can be found in $BinPath"
+}
 
 Say "Installation finished"