From f26054fe5585c8b0d89cb2e70eac647d6b6fe3c6 Mon Sep 17 00:00:00 2001
From: Keith Hill <r_keith_hill@hotmail.com>
Date: Sat, 2 Mar 2019 20:53:52 -0700
Subject: [PATCH 1/6] Pipe help system output through Out-String -Width when
 not using more

This fixes #7175 by using Out-String to properly wrap text before
sending to less or the user specified PAGER.
---
 .../engine/InitialSessionState.cs                             | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/System.Management.Automation/engine/InitialSessionState.cs b/src/System.Management.Automation/engine/InitialSessionState.cs
index 852c7e88152..1d91f06efc9 100644
--- a/src/System.Management.Automation/engine/InitialSessionState.cs
+++ b/src/System.Management.Automation/engine/InitialSessionState.cs
@@ -4205,11 +4205,11 @@ .FORWARDHELPCATEGORY Cmdlet
 
         # Respect PAGER, use more on Windows, and use less on Linux
         if ($customPagerCommand) {
-            $help | & $customPagerCommand $customPagerCommandArgs
+            $help | Out-String -Width ([System.Console]::WindowWidth - 1) | & $customPagerCommand $customPagerCommandArgs
         } elseif ($IsWindows) {
             $help | more.com
         } else {
-            $help | less -Ps""Page %db?B of %D:.\. Press h for help or q to quit\.$""
+            $help | Out-String -Width ([System.Console]::WindowWidth - 1) | less -Ps""Page %db?B of %D:.\. Press h for help or q to quit\.$""
         }
     }
 ";

From 1f06d43a76ada6d623a191532104a318790e3391 Mon Sep 17 00:00:00 2001
From: Keith Hill <r_keith_hill@hotmail.com>
Date: Sun, 3 Mar 2019 00:19:21 -0700
Subject: [PATCH 2/6] Set the string output width when sending help to pager
 app

Fix #7175
---
 .../engine/InitialSessionState.cs             | 39 ++++++++++++-------
 1 file changed, 24 insertions(+), 15 deletions(-)

diff --git a/src/System.Management.Automation/engine/InitialSessionState.cs b/src/System.Management.Automation/engine/InitialSessionState.cs
index 1d91f06efc9..c7f1556db98 100644
--- a/src/System.Management.Automation/engine/InitialSessionState.cs
+++ b/src/System.Management.Automation/engine/InitialSessionState.cs
@@ -4176,10 +4176,17 @@ .FORWARDHELPCATEGORY Cmdlet
     }
     elseif ($help -ne $null)
     {
-        $customPagerCommand = """"
-        $customPagerCommandArgs = """"
-        $customPagerCommandLine = """"
+        # Use more on Windows, and use less on Linux by default
+        if ($IsWindows) {
+            $pagerCommand = 'more.com'
+            $pagerArgs = $null
+        }
+        else {
+            $pagerCommand = 'less'
+            $pagerArgs = '-Ps""Page %db?B of %D:.\. Press h for help or q to quit\.$""'
+        }
 
+        # Respect PAGER environment variable which allows user to specify a custom pager
         if ($env:PAGER)
         {
             $customPagerCommandLine = $env:PAGER
@@ -4193,23 +4200,25 @@ .FORWARDHELPCATEGORY Cmdlet
             if (-not $cmds) {
                 # Custom command is invalid; ignore it, but issue a warning.
                 Write-Warning ""Ignoring invalid custom-paging utility command line specified in `$env:PAGER: $customPagerCommandLine""
-                $customPagerCommand = $null # use default command
             }
             elseif ($cmds.Count -eq 1 -and $cmds[0].Source -eq $customPagerCommandLine) {
-                # The full command line is an unquoted path to an existing executable
-                # with embedded spaces.
-                $customPagerCommand = $customPagerCommandLine
-                $customPagerCommandArgs = $null
+                # The full command line is an unquoted path to an existing executable with embedded spaces.
+                $pagerCommand = $customPagerCommandLine
+                $pagerArgs = $null
+            }
+            else {
+                $pagerCommand = $customPagerCommand
+                $pagerArgs = $customPagerCommandArgs
             }
         }
 
-        # Respect PAGER, use more on Windows, and use less on Linux
-        if ($customPagerCommand) {
-            $help | Out-String -Width ([System.Console]::WindowWidth - 1) | & $customPagerCommand $customPagerCommandArgs
-        } elseif ($IsWindows) {
-            $help | more.com
-        } else {
-            $help | Out-String -Width ([System.Console]::WindowWidth - 1) | less -Ps""Page %db?B of %D:.\. Press h for help or q to quit\.$""
+        if ((Get-Command $pagerCommand -ErrorAction Ignore).CommandType -eq 'Application') {
+            # If the pager is an application, format the output width before sending to the app.
+            $help | Out-String -Stream -Width ([System.Console]::WindowWidth - 1) | & $pagerCommand $pagerArgs
+        }
+        else {
+            # If the pager is a PowerShell function or script, pipe directly into it.
+            $help | & $pagerCommand $pagerArgs
         }
     }
 ";

From 790d2e3d2aba952b1ae23dfb943cf33967e9276e Mon Sep 17 00:00:00 2001
From: Keith Hill <r_keith_hill@hotmail.com>
Date: Sun, 3 Mar 2019 01:10:49 -0700
Subject: [PATCH 3/6] Fix #8912 by using PS tokenize to get custom pager cmd &
 args

---
 .../engine/InitialSessionState.cs             | 61 +++++++++++--------
 1 file changed, 37 insertions(+), 24 deletions(-)

diff --git a/src/System.Management.Automation/engine/InitialSessionState.cs b/src/System.Management.Automation/engine/InitialSessionState.cs
index c7f1556db98..28b1688b42f 100644
--- a/src/System.Management.Automation/engine/InitialSessionState.cs
+++ b/src/System.Management.Automation/engine/InitialSessionState.cs
@@ -4176,45 +4176,58 @@ .FORWARDHELPCATEGORY Cmdlet
     }
     elseif ($help -ne $null)
     {
-        # Use more on Windows, and use less on Linux by default
+        $pagerArgs = $null
+        
+        # By default use more on Windows and less on Linux.
         if ($IsWindows) {
             $pagerCommand = 'more.com'
-            $pagerArgs = $null
         }
         else {
             $pagerCommand = 'less'
             $pagerArgs = '-Ps""Page %db?B of %D:.\. Press h for help or q to quit\.$""'
         }
 
-        # Respect PAGER environment variable which allows user to specify a custom pager
-        if ($env:PAGER)
-        {
-            $customPagerCommandLine = $env:PAGER
-
-            # Split the command line into tokens, respecting quoting.
-            $customPagerCommand, $customPagerCommandArgs = & { Write-Output -- $customPagerCommandLine }
-
-            # See if the first token refers to a known command (executable),
-            # and if not, see if the command line as a whole is an executable path.
-            $cmds = Get-Command $customPagerCommand, $customPagerCommandLine -ErrorAction Ignore
-            if (-not $cmds) {
-                # Custom command is invalid; ignore it, but issue a warning.
-                Write-Warning ""Ignoring invalid custom-paging utility command line specified in `$env:PAGER: $customPagerCommandLine""
-            }
-            elseif ($cmds.Count -eq 1 -and $cmds[0].Source -eq $customPagerCommandLine) {
-                # The full command line is an unquoted path to an existing executable with embedded spaces.
-                $pagerCommand = $customPagerCommandLine
-                $pagerArgs = $null
+        # Respect PAGER environment variable which allows user to specify a custom pager.
+        # Ignore a pure whitespace PAGER value as that would cause the tokenizer to return 0 tokens.
+        if (![string]::IsNullOrWhitespace($env:PAGER)) {
+            if (Get-Command $env:PAGER -ErrorAction Ignore) {
+                # Entire PAGER value corresponds to a single command.
+                $pagerCommand = $env:PAGER
             }
             else {
-                $pagerCommand = $customPagerCommand
-                $pagerArgs = $customPagerCommandArgs
+                # PAGER value is not a valid command, check if PAGER command and arguments have been specified.
+                # Tokenize the specified $env:PAGER value. Ignore tokenizing errors since any errors may be valid
+                # argument syntax for the paging utility.
+                $errs = $null
+                $tokens = [System.Management.Automation.PSParser]::Tokenize($env:PAGER, [ref]$errs)
+
+                $customPagerCommand = $tokens[0].Content
+                if (!(Get-Command $customPagerCommand -ErrorAction Ignore)) {
+                    # Custom pager command is invalid, issue a warning.
+                    Write-Warning ""Ignoring invalid custom-paging utility command line specified in `$env:PAGER: $env:PAGER""
+                }
+                elseif ($tokens.Count -eq 1) {
+                    $pagerCommand = $customPagerCommand
+                }
+                else {
+                    # This approach will preserve all the pagers args.
+                    $pagerCommand = $customPagerCommand
+                    $pagerArgs = $env:PAGER.Substring($tokens[1].Start)
+                }
             }
         }
 
         if ((Get-Command $pagerCommand -ErrorAction Ignore).CommandType -eq 'Application') {
             # If the pager is an application, format the output width before sending to the app.
-            $help | Out-String -Stream -Width ([System.Console]::WindowWidth - 1) | & $pagerCommand $pagerArgs
+            if ($pagerArgs) {
+                # Supply pager arguments to an application without any PowerShell parsing of the arguments.
+                $env:_PSPAGER_ARGS = $pagerArgs
+                $help | Out-String -Stream -Width ([System.Console]::WindowWidth - 1) | & $pagerCommand --% %_PSPAGER_ARGS%
+                Remove-Item Env:\_PSPAGER_ARGS -ErrorAction Ignore
+            }
+            else {
+                $help | Out-String -Stream -Width ([System.Console]::WindowWidth - 1) | & $pagerCommand
+            }
         }
         else {
             # If the pager is a PowerShell function or script, pipe directly into it.

From 9374c796688f8c2bf725577535d405aa69d505f6 Mon Sep 17 00:00:00 2001
From: Keith Hill <r_keith_hill@hotmail.com>
Date: Sun, 3 Mar 2019 13:57:00 -0700
Subject: [PATCH 4/6] Fix macOS/Linux test failures

---
 .../engine/InitialSessionState.cs             | 23 +++++++++----------
 1 file changed, 11 insertions(+), 12 deletions(-)

diff --git a/src/System.Management.Automation/engine/InitialSessionState.cs b/src/System.Management.Automation/engine/InitialSessionState.cs
index 28b1688b42f..72ad1591425 100644
--- a/src/System.Management.Automation/engine/InitialSessionState.cs
+++ b/src/System.Management.Automation/engine/InitialSessionState.cs
@@ -4176,11 +4176,10 @@ .FORWARDHELPCATEGORY Cmdlet
     }
     elseif ($help -ne $null)
     {
-        $pagerArgs = $null
-        
         # By default use more on Windows and less on Linux.
         if ($IsWindows) {
             $pagerCommand = 'more.com'
+            $pagerArgs = $null
         }
         else {
             $pagerCommand = 'less'
@@ -4193,6 +4192,7 @@ .FORWARDHELPCATEGORY Cmdlet
             if (Get-Command $env:PAGER -ErrorAction Ignore) {
                 # Entire PAGER value corresponds to a single command.
                 $pagerCommand = $env:PAGER
+                $pagerArgs = $null
             }
             else {
                 # PAGER value is not a valid command, check if PAGER command and arguments have been specified.
@@ -4206,31 +4206,30 @@ .FORWARDHELPCATEGORY Cmdlet
                     # Custom pager command is invalid, issue a warning.
                     Write-Warning ""Ignoring invalid custom-paging utility command line specified in `$env:PAGER: $env:PAGER""
                 }
-                elseif ($tokens.Count -eq 1) {
-                    $pagerCommand = $customPagerCommand
-                }
                 else {
                     # This approach will preserve all the pagers args.
                     $pagerCommand = $customPagerCommand
-                    $pagerArgs = $env:PAGER.Substring($tokens[1].Start)
+                    $pagerArgs = if ($tokens.Count -gt 1) {$env:PAGER.Substring($tokens[1].Start)} else {$null}
                 }
             }
         }
 
+        # If the pager is an application, format the output width before sending to the app.
         if ((Get-Command $pagerCommand -ErrorAction Ignore).CommandType -eq 'Application') {
-            # If the pager is an application, format the output width before sending to the app.
+            $consoleWidth = [System.Console]::WindowWidth
+
             if ($pagerArgs) {
                 # Supply pager arguments to an application without any PowerShell parsing of the arguments.
-                $env:_PSPAGER_ARGS = $pagerArgs
-                $help | Out-String -Stream -Width ([System.Console]::WindowWidth - 1) | & $pagerCommand --% %_PSPAGER_ARGS%
-                Remove-Item Env:\_PSPAGER_ARGS -ErrorAction Ignore
+                # Leave environment variable to help user debug arguments supplied in $env:PAGER.
+                $env:__PSPAGER_ARGS = $pagerArgs
+                $help | Out-String -Stream -Width ($consoleWidth - 1) | & $pagerCommand --% %__PSPAGER_ARGS%
             }
             else {
-                $help | Out-String -Stream -Width ([System.Console]::WindowWidth - 1) | & $pagerCommand
+                $help | Out-String -Stream -Width ($consoleWidth - 1) | & $pagerCommand
             }
         }
         else {
-            # If the pager is a PowerShell function or script, pipe directly into it.
+            # The pager command is a PowerShell function, script or alias, so pipe directly into it.
             $help | & $pagerCommand $pagerArgs
         }
     }

From 9ecd62ce0169b352638e1925bafcb0643dd98b4e Mon Sep 17 00:00:00 2001
From: Keith Hill <r_keith_hill@hotmail.com>
Date: Sun, 3 Mar 2019 14:59:16 -0700
Subject: [PATCH 5/6] It appears that while running in tests, ConsoleWidth is
 0, set min val

---
 src/System.Management.Automation/engine/InitialSessionState.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/System.Management.Automation/engine/InitialSessionState.cs b/src/System.Management.Automation/engine/InitialSessionState.cs
index 72ad1591425..8aa6c65f098 100644
--- a/src/System.Management.Automation/engine/InitialSessionState.cs
+++ b/src/System.Management.Automation/engine/InitialSessionState.cs
@@ -4216,7 +4216,7 @@ .FORWARDHELPCATEGORY Cmdlet
 
         # If the pager is an application, format the output width before sending to the app.
         if ((Get-Command $pagerCommand -ErrorAction Ignore).CommandType -eq 'Application') {
-            $consoleWidth = [System.Console]::WindowWidth
+            $consoleWidth = [System.Math]::Max([System.Console]::WindowWidth, 20)
 
             if ($pagerArgs) {
                 # Supply pager arguments to an application without any PowerShell parsing of the arguments.

From bb62a371f9324ff971a6c571888b4d88d694e7c0 Mon Sep 17 00:00:00 2001
From: Keith Hill <r_keith_hill@hotmail.com>
Date: Tue, 9 Apr 2019 22:15:10 -0600
Subject: [PATCH 6/6] Address PR feedback

---
 src/System.Management.Automation/engine/InitialSessionState.cs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/System.Management.Automation/engine/InitialSessionState.cs b/src/System.Management.Automation/engine/InitialSessionState.cs
index 8aa6c65f098..a578d21e1ba 100644
--- a/src/System.Management.Automation/engine/InitialSessionState.cs
+++ b/src/System.Management.Automation/engine/InitialSessionState.cs
@@ -4204,7 +4204,7 @@ .FORWARDHELPCATEGORY Cmdlet
                 $customPagerCommand = $tokens[0].Content
                 if (!(Get-Command $customPagerCommand -ErrorAction Ignore)) {
                     # Custom pager command is invalid, issue a warning.
-                    Write-Warning ""Ignoring invalid custom-paging utility command line specified in `$env:PAGER: $env:PAGER""
+                    Write-Warning ""Custom-paging utility command not found. Ignoring command specified in `$env:PAGER: $env:PAGER""
                 }
                 else {
                     # This approach will preserve all the pagers args.