From 3d76d59b7339c7d3724bedcee205933578801a41 Mon Sep 17 00:00:00 2001
From: aviau <alexandre@alexandreviau.net>
Date: Thu, 7 Jun 2018 15:23:05 -0400
Subject: [PATCH] memmap: opening empty path should be an error

---
 lstater_test.go | 10 +++++-----
 memmap.go       |  5 +++++
 memmap_test.go  | 10 ++++++++++
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/lstater_test.go b/lstater_test.go
index 477924f..5723224 100644
--- a/lstater_test.go
+++ b/lstater_test.go
@@ -73,7 +73,7 @@ func TestLstatIfPossible(t *testing.T) {
 	}
 
 	testLstat := func(l Lstater, pathFile, pathSymlink string) {
-		shouldLstat := pathSymlink != ""
+		shouldLstat := pathSymlink != FilePathSeparator
 		statRegular := checkLstat(l, pathFile, shouldLstat)
 		statSymlink := checkLstat(l, pathSymlink, shouldLstat)
 		if statRegular == nil || statSymlink == nil {
@@ -81,7 +81,7 @@ func TestLstatIfPossible(t *testing.T) {
 		}
 
 		symSym := statSymlink.Mode()&os.ModeSymlink == os.ModeSymlink
-		if symSym == (pathSymlink == "") {
+		if symSym == (pathSymlink == FilePathSeparator) {
 			t.Fatal("expected the FileInfo to describe the symlink")
 		}
 
@@ -95,8 +95,8 @@ func TestLstatIfPossible(t *testing.T) {
 	testLstat(overlayFs1, pathFile, pathSymlink)
 	testLstat(overlayFs2, pathFile, pathSymlink)
 	testLstat(basePathFs, "afero.txt", "symafero.txt")
-	testLstat(overlayFsMemOnly, pathFileMem, "")
-	testLstat(basePathFsMem, "aferom.txt", "")
+	testLstat(overlayFsMemOnly, pathFileMem, FilePathSeparator)
+	testLstat(basePathFsMem, "aferom.txt", FilePathSeparator)
 	testLstat(roFs, pathFile, pathSymlink)
-	testLstat(roFsMem, pathFileMem, "")
+	testLstat(roFsMem, pathFileMem, FilePathSeparator)
 }
diff --git a/memmap.go b/memmap.go
index 09498e7..8d163df 100644
--- a/memmap.go
+++ b/memmap.go
@@ -159,6 +159,11 @@ func (m *MemMapFs) MkdirAll(path string, perm os.FileMode) error {
 
 // Handle some relative paths
 func normalizePath(path string) string {
+	// Cleaning an empty path would result in "."
+	if path == "" {
+		return path
+	}
+
 	path = filepath.Clean(path)
 
 	switch path {
diff --git a/memmap_test.go b/memmap_test.go
index 47414ab..5d9ac68 100644
--- a/memmap_test.go
+++ b/memmap_test.go
@@ -449,3 +449,13 @@ func TestMemFsUnexpectedEOF(t *testing.T) {
 		t.Fatal("Expected ErrUnexpectedEOF")
 	}
 }
+
+func TestStatEmptyPath(t *testing.T) {
+	t.Parallel()
+
+	fs := NewMemMapFs()
+
+	if _, err := fs.Stat(""); !os.IsNotExist(err) {
+		t.Fatal(err)
+	}
+}