From d528bf5d3df65655a027cdb46d6734f91518bc7b Mon Sep 17 00:00:00 2001
From: Eugene Samoylov <eugenesmlv@gmail.com>
Date: Tue, 15 Oct 2019 00:32:37 +0000
Subject: [PATCH] Fix for `Get-Content -ReadCount 0` behavior when
 `-TotalCount` is set (#10749)

---
 .../commands/management/GetContentCommand.cs                | 2 +-
 .../Microsoft.PowerShell.Management/Get-Content.Tests.ps1   | 6 ++++++
 2 files changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/Microsoft.PowerShell.Commands.Management/commands/management/GetContentCommand.cs b/src/Microsoft.PowerShell.Commands.Management/commands/management/GetContentCommand.cs
index bc1e87042..bf7d6037b 100644
--- a/src/Microsoft.PowerShell.Commands.Management/commands/management/GetContentCommand.cs
+++ b/src/Microsoft.PowerShell.Commands.Management/commands/management/GetContentCommand.cs
@@ -206,7 +206,7 @@ namespace Microsoft.PowerShell.Commands
                             // I am using TotalCount - countToRead so that I don't
                             // have to worry about overflow
 
-                            if ((TotalCount > 0) && (TotalCount - countToRead < countRead))
+                            if ((TotalCount > 0) && (countToRead == 0 || (TotalCount - countToRead < countRead)))
                             {
                                 countToRead = TotalCount - countRead;
                             }
diff --git a/test/powershell/Modules/Microsoft.PowerShell.Management/Get-Content.Tests.ps1 b/test/powershell/Modules/Microsoft.PowerShell.Management/Get-Content.Tests.ps1
index 4c4e9337f..ffb198daa 100644
--- a/test/powershell/Modules/Microsoft.PowerShell.Management/Get-Content.Tests.ps1
+++ b/test/powershell/Modules/Microsoft.PowerShell.Management/Get-Content.Tests.ps1
@@ -342,6 +342,12 @@ baz
             $expected[1] = $thirdLine
             Compare-Object -ReferenceObject $expected -DifferenceObject $result | Should -BeNullOrEmpty
         }
+        It "Should return the same number of first lines as set in -TotalCount at one time for -ReadCount 0" {
+            $result = Get-Content -Path $testPath -TotalCount 3 -ReadCount 0
+            $result.Length | Should -Be 3
+            $expected = $firstLine,$secondLine,$thirdLine
+            Compare-Object -ReferenceObject $expected -DifferenceObject $result | Should -BeNullOrEmpty
+        }
         It "A warning should be emitted if both -AsByteStream and -Encoding are used together" {
             [byte[]][char[]]"test" | Set-Content -Encoding Unicode -AsByteStream "${TESTDRIVE}\bfile.txt" -WarningVariable contentWarning *> $null
             $contentWarning.Message | Should -Match "-AsByteStream"