fix: panic when calling SplitFilepath on windows

Unix unit test improved. Windows unit test included.

Signed-off-by: Timofey Kirillov <timofey.kirillov@flant.com>

pkg/util/path.go

@@ -5,6 +5,7 @@ import (
 	"os"
 	"os/user"
 	"path/filepath"
+	"runtime"
 	"strings"
 	"unicode/utf8"
 )
@@ -37,20 +38,27 @@ func ExpandPath(path string) string {
 }
 
 func SplitFilepath(path string) (result []string) {
+	separator := os.PathSeparator
+
 	path = filepath.FromSlash(path)
 	path = filepath.Clean(path)
 
-	if filepath.IsAbs(path) {
-		p, err := filepath.Rel(string(os.PathSeparator), path)
+	if runtime.GOOS == "windows" {
+		sepStr := string(separator)
+		uncRootPath := fmt.Sprintf("%s%s", sepStr, sepStr)
+
+		path = strings.TrimPrefix(path, uncRootPath)
+		path = strings.TrimPrefix(path, sepStr)
+		path = strings.TrimSuffix(path, sepStr)
+	} else if filepath.IsAbs(path) {
+		p, err := filepath.Rel(string(separator), path)
 		if err != nil {
 			panic(fmt.Sprintf("unable to get relative path for %q", path))
 		}
 		path = p
 	}
 
-	separator := os.PathSeparator
-
-	if path == "." || path == string(separator) {
+	if path == "" || path == "." || path == string(separator) {
 		return nil
 	}
 

pkg/util/path_test.go → pkg/util/path_unix_test.go

@@ -1,3 +1,5 @@
+//go:build !windows
+
 package util_test
 
 import (
@@ -55,7 +57,7 @@ type splitPathTest struct {
 	expectedPathParts []string
 }
 
-var _ = DescribeTable("split path",
+var _ = DescribeTable("split unix path",
 	func(t splitPathTest) {
 		parts := util.SplitFilepath(t.path)
 		Expect(parts).To(Equal(t.expectedPathParts))
@@ -64,6 +66,10 @@ var _ = DescribeTable("split path",
 		path:              "/",
 		expectedPathParts: nil,
 	}),
+	Entry("root dir", splitPathTest{
+		path:              "/mydir/",
+		expectedPathParts: []string{"mydir"},
+	}),
 	Entry("unnormalized root path", splitPathTest{
 		path:              "////",
 		expectedPathParts: nil,

pkg/util/path_windows_test.go

@@ -0,0 +1,58 @@
+//go:build windows
+
+package util_test
+
+import (
+	. "github.com/onsi/ginkgo/v2"
+	. "github.com/onsi/gomega"
+
+	"github.com/werf/werf/pkg/util"
+)
+
+type splitPathTest struct {
+	path              string
+	expectedPathParts []string
+}
+
+var _ = DescribeTable("split windows path",
+	func(t splitPathTest) {
+		parts := util.SplitFilepath(t.path)
+		Expect(parts).To(Equal(t.expectedPathParts))
+	},
+	Entry("UNC absolute path", splitPathTest{
+		path:              `\\Server2\Share\Test\Foo.txt`,
+		expectedPathParts: []string{"Server2", "Share", "Test", "Foo.txt"},
+	}),
+	Entry("UNC absolute non-normalized path", splitPathTest{
+		path:              `\\\\\\Server2\\\Share\\\Test\Foo.txt`,
+		expectedPathParts: []string{"Server2", "Share", "Test", "Foo.txt"},
+	}),
+	Entry("UNC root path", splitPathTest{
+		path:              `\\`,
+		expectedPathParts: nil,
+	}),
+	Entry("root disk path", splitPathTest{
+		path:              `D:\`,
+		expectedPathParts: []string{`D:`},
+	}),
+	Entry("unnormalized root disk path", splitPathTest{
+		path:              `D:\\\\\\`,
+		expectedPathParts: []string{`D:`},
+	}),
+	Entry("empty path", splitPathTest{
+		path:              "",
+		expectedPathParts: nil,
+	}),
+	Entry("absolute path to file", splitPathTest{
+		path:              `D:\path\to\file`,
+		expectedPathParts: []string{`D:`, "path", "to", "file"},
+	}),
+	Entry("absolute path to dir", splitPathTest{
+		path:              `D:\path\to\dir\`,
+		expectedPathParts: []string{`D:`, "path", "to", "dir"},
+	}),
+	Entry("relative path", splitPathTest{
+		path:              `path\to\dir\or\file`,
+		expectedPathParts: []string{"path", "to", "dir", "or", "file"},
+	}),
+)