Dongbo Wang (daxian-dbw) · Oct 12, 2016 · Oct 1, 2016 · Oct 1, 2016 · Oct 1, 2016 · Oct 7, 2016
@@ -1564,6 +1564,7 @@ public static class InternalTestHooks
         internal static bool ForceScriptBlockLogging;
         internal static bool UseDebugAmsiImplementation;
         internal static bool BypassAppLockerPolicyCaching;
+        internal static bool BypassOnlineHelpRetrieval;
         // It's useful to test that we don't depend on the ScriptBlock and AST objects and can use a re-parsed version.
         internal static bool IgnoreScriptBlockCache;
 

@@ -14,6 +14,10 @@
 using System.Management.Automation.Internal;
 using System.Management.Automation.Help;
 using System.Runtime.InteropServices;
+using System.IO;
+#if !UNIX
+using Microsoft.Win32;
+#endif
 
 namespace Microsoft.PowerShell.Commands
 {
@@ -615,18 +619,39 @@ private void LaunchOnlineHelp(Uri uriToLaunch)
                     "https");
             }
 
+            // we use this test hook is to avoid actually calling out to another process
+            if (InternalTestHooks.BypassOnlineHelpRetrieval)
+            {
+                this.WriteObject(string.Format(CultureInfo.InvariantCulture, HelpDisplayStrings.OnlineHelpUri, uriToLaunch.OriginalString));
+                return;
+            }
+
             Exception exception = null;
+            bool wrapCaughtException = true;
             try
             {
                 this.WriteVerbose(string.Format(CultureInfo.InvariantCulture, HelpDisplayStrings.OnlineHelpUri, uriToLaunch.OriginalString));
                 System.Diagnostics.Process browserProcess = new System.Diagnostics.Process();
-
 #if UNIX
                 browserProcess.StartInfo.FileName = Platform.IsLinux ? "xdg-open" : /* OS X */ "open";
                 browserProcess.StartInfo.Arguments = uriToLaunch.OriginalString;
                 browserProcess.Start();
 #elif CORECLR
-                throw new PlatformNotSupportedException();
+                // On FullCLR, ProcessStartInfo.UseShellExecute is true by default. This means that the shell will be used when starting the process.
+                // On CoreCLR, UseShellExecute is not supported. To work around this, we check if there is a default browser in the system.
+                // If there is, we lunch it to open the HelpURI. If there isn't, we error out.
+                string webBrowserPath = GetDefaultWebBrowser();
+                if (webBrowserPath == null)
+                {
+                    wrapCaughtException = false;
+                    exception = PSTraceSource.NewInvalidOperationException(HelpErrors.CannotLaunchURI, uriToLaunch.OriginalString);
+                }
+                else
+                {
+                    browserProcess.StartInfo = new ProcessStartInfo(webBrowserPath);
+                    browserProcess.StartInfo.Arguments = "\"" + uriToLaunch.OriginalString + "\"";
+                    browserProcess.Start();
+                }
 #else
                 browserProcess.StartInfo.FileName = uriToLaunch.OriginalString;
                 browserProcess.Start();
@@ -643,10 +668,53 @@ private void LaunchOnlineHelp(Uri uriToLaunch)
 
             if (null != exception)
             {
-                throw PSTraceSource.NewInvalidOperationException(exception, HelpErrors.CannotLaunchURI, uriToLaunch.OriginalString);
+                if (wrapCaughtException)
+                    throw PSTraceSource.NewInvalidOperationException(exception, HelpErrors.CannotLaunchURI, uriToLaunch.OriginalString);
+                else
+                    throw exception;
             }
         }
 
+#if !UNIX
+        /// <summary>
+        /// Gets the path to the default browser by querying the Windows registry.
+        /// </summary>
+        /// <returns></returns>
+        private string GetDefaultWebBrowser()
+        {
+            // Check if there is a default browser in the system.
+            const string httpRegkey = @"HKEY_CURRENT_USER\Software\Microsoft\Windows\Shell\Associations\UrlAssociations\http\UserChoice";
+            object progId = Registry.GetValue(httpRegkey, "ProgId", null);
+            if (progId != null)
+            {
+                // Query the registry to find the web browser path.
+                using (RegistryKey browserRegKey = Registry.ClassesRoot.OpenSubKey(progId + "\\shell\\open\\command", false))
+                {
+                    string browserPath = browserRegKey?.GetValue(null)?.ToString().Replace(/* remove the quotes */ "\"", "");
+                    if (!string.IsNullOrEmpty(browserPath))
+                    {
+                        const string exeExtension = ".exe";
+                        if (!browserPath.EndsWith(exeExtension, StringComparison.OrdinalIgnoreCase))
+                        {
+                            // Remove any extra chars in the path after ".exe".
+                            int extIndex = browserPath.LastIndexOf(exeExtension, StringComparison.OrdinalIgnoreCase);
+                            browserPath = extIndex > 0 ? browserPath.Substring(0, extIndex + exeExtension.Length) : string.Empty;
+                        }
+
+                        // Make sure the path to the default browser exists.
+                        if (File.Exists(browserPath))
+                        {
+                            return browserPath;
+                        }
+                    }
+                }
+            }
+
+            // By default, return null.
+            return null;
+        }
+#endif
+
         #endregion
 
         private void HelpSystem_OnProgress(object sender, HelpProgressInfo arg)

@@ -0,0 +1,94 @@
+Describe 'Online help tests for PowerShell Core Cmdlets' -Tags "CI" {
+
+    # The csv files (V2Cmdlets.csv and V3Cmdlets.csv) contain a list of cmdlets and expected HelpURIs.
+    # The HelpURI is part of the cmdlet metadata, and when the user runs 'get-help <cmdletName> -online'
+    # the browser navigates to the address in the HelpURI. However, if a help file is present, the HelpURI
+    # on the file take precedence over the one in the cmdlet metadata. Therefore, the help content
+    # in the box needs to be deleted before running the tests, because otherwise, the HelpURI
+    # (when calling get-help -online) might not matched the one in the csv file.
+
+    # Currently update-help does not work on Linux (see  https://github.com/PowerShell/PowerShell/issues/951),
+    # so if the help content is deleted, we do not have a way to install it back, and any subsequent
+    # 'get-help' tests which depend on the help content will fail. Until this update-help issue is fixed,
+    # we need to skip these tests on Linux and OSX.
+
+    $skipTest = ([System.Management.Automation.Platform]::IsLinux -or [System.Management.Automation.Platform]::IsOSX)
+
+    BeforeAll {
+
+        # There is a bug in Linux in which a 'Boolean value defined inside Describe block cannot be evaluated properly 
+        # in if statement inside BeforeAll block on Linux' Becuase of this, I need to define the bool value again inside the block.
+        # See https://github.com/PowerShell/PowerShell/issues/2445
+        #
+        $skipTest = ([System.Management.Automation.Platform]::IsLinux -or [System.Management.Automation.Platform]::IsOSX)
+
+        if (-not $skipTest)
+        {
+            # Enable the test hook
+            [system.management.automation.internal.internaltesthooks]::SetTestHook('BypassOnlineHelpRetrieval', $true)
+
+            # Remove the help content
+            Write-Verbose "Deleting help content for get-help -online tests" -Verbose
+            $path = Join-Path $PSHOME (Get-UICulture).Name
+            Get-ChildItem "$path\*dll-help.xml" -Recurse -ErrorAction SilentlyContinue | Remove-Item -Force -ErrorAction SilentlyContinue
+        }
+    }
+
+    AfterAll {
+        if (-not $skipTest)
+        {
+            # Disable the test hook
+            [system.management.automation.internal.internaltesthooks]::SetTestHook('BypassOnlineHelpRetrieval', $false)
+        }
+    }
+
+    foreach ($filePath in @("$PSScriptRoot\testdata\HelpURI\V2Cmdlets.csv", "$PSScriptRoot\testdata\HelpURI\V3Cmdlets.csv"))
+    {
+        $cmdletList = Import-Csv $filePath -ea Stop
+
+        foreach ($cmdlet in $cmdletList)
+        {
+            # If the cmdlet is not preset in CoreCLR, skip it.
+            if (Get-Command $cmdlet.TopicTitle -ea SilentlyContinue)
+            {
+                # TopicTitle - is the cmdlet name in the csv file
+                # HelpURI - is the expected help URI in the csv file
+
+                It "Validate 'get-help $($cmdlet.TopicTitle) -Online'" -skip:$skipTest {
+                    $actualURI = Get-Help $cmdlet.TopicTitle -Online
+                    $actualURI = $actualURI.Replace("Help URI: ","")
+                    $actualURI | Should Be $cmdlet.HelpURI
+                }
+            }
+        }
+    }
+}
+
+Describe 'Get-Help -Online opens the default web browser and navigates to the cmdlet help content' -Tags "Feature" {
+
+    $skipTest = [System.Management.Automation.Platform]::IsIoT -or
+                [System.Management.Automation.Platform]::IsNanoServer
+
+    It "Get-Help get-process -online" -skip:$skipTest {
+
+        { Get-Help get-process -online } | Should Not Throw
+    }
+}
+
+Describe 'Get-Help -Online is not supported on Nano Server and IoT' -Tags "CI" {
+
+    $skipTest = -not ([System.Management.Automation.Platform]::IsIoT -or [System.Management.Automation.Platform]::IsNanoServer)
+
+    It "Get-help -online <cmdletName> throws InvalidOperation." -skip:$skipTest {
+
+        try
+        {
+            Get-Help Get-Help -Online
+            throw "Execution should not have succeeded"
+        }
+        catch
+        {
+            $_.FullyQualifiedErrorId | Should Be "InvalidOperation,Microsoft.PowerShell.Commands.GetHelpCommand"
+        }
+    }
+}