From 4ac817f5ad3f2a6118987c0f82fed9dc320a4347 Mon Sep 17 00:00:00 2001
From: Ladi Prosek <laprosek@microsoft.com>
Date: Fri, 12 Feb 2021 13:14:01 +0100
Subject: [PATCH] Back-compat workaround

---
 src/Shared/FileMatcher.cs | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/Shared/FileMatcher.cs b/src/Shared/FileMatcher.cs
index c31de6d7c80..6628b3025dd 100644
--- a/src/Shared/FileMatcher.cs
+++ b/src/Shared/FileMatcher.cs
@@ -1061,10 +1061,27 @@ struct RecursionState
             {
                 return Enumerable.Empty<string>();
             }
+
+            // Back-compat hack: We don't use case-insensitive file enumeration I/O on Linux so the behavior is different depending
+            // on the NeedsToProcessEachFile flag. If the flag is false and matching is done within the _getFileSystemEntries call,
+            // it is case sensitive. If the flag is true and matching is handled with MatchFileRecursionStep, it is case-insensitive.
+            // TODO: Can we fix this by using case-insensitive file I/O on Linux?
+            bool forceFileProcessing = false;
+            string filespec;
+            if (NativeMethodsShared.IsLinux && recursionState.SearchData.DirectoryPattern != null)
+            {
+                filespec = "*.*";
+                forceFileProcessing = true;
+            }
+            else
+            {
+                filespec = recursionState.SearchData.Filespec;
+            }
+
             IEnumerable<string> files = _getFileSystemEntries(FileSystemEntity.Files, recursionState.BaseDirectory,
-                recursionState.SearchData.Filespec, projectDirectory, stripProjectDirectory);
+                filespec, projectDirectory, stripProjectDirectory);
 
-            if (!stepResult.NeedsToProcessEachFile)
+            if (!forceFileProcessing && !stepResult.NeedsToProcessEachFile)
             {
                 return files;
             }