From d518f3b44ae3b3dd97838b583a1caef12a9f9464 Mon Sep 17 00:00:00 2001
From: Adrien CABARBAYE <adrien.cabarbaye@arm.com>
Date: Thu, 5 Sep 2024 23:42:04 +0100
Subject: [PATCH] :sparkles: `[filesystem]` Add a way to determine all parents
 of a path (#503)

<!--
Copyright (C) 2020-2022 Arm Limited or its affiliates and Contributors.
All rights reserved.
SPDX-License-Identifier: Apache-2.0
-->
### Description
try to give the same functionality as
[pathlib](https://github.com/python/cpython/blob/3.12/Lib/pathlib.py#L263)

### Test Coverage

<!--
Please put an `x` in the correct box e.g. `[x]` to indicate the testing
coverage of this change.
-->

- [x]  This change is covered by existing or additional automated tests.
- [ ] Manual testing has been performed (and evidence provided) as
automated testing was not feasible.
- [ ] Additional tests are not required for this change (e.g.
documentation update).
---
 changes/20240905230606.feature    |  1 +
 utils/filesystem/filepath.go      | 30 ++++++++++++++++-
 utils/filesystem/filepath_test.go | 56 +++++++++++++++++++++++++++++++
 3 files changed, 86 insertions(+), 1 deletion(-)
 create mode 100644 changes/20240905230606.feature

diff --git a/changes/20240905230606.feature b/changes/20240905230606.feature
new file mode 100644
index 0000000000..955a13c3b2
--- /dev/null
+++ b/changes/20240905230606.feature
@@ -0,0 +1 @@
+:sparkles: [filesystem] Add a way to determine all parents of a path similar to python's [pathlib](https://docs.python.org/3/library/pathlib.html#pathlib.PurePath.parents)
diff --git a/utils/filesystem/filepath.go b/utils/filesystem/filepath.go
index b13b220cf8..84742da954 100644
--- a/utils/filesystem/filepath.go
+++ b/utils/filesystem/filepath.go
@@ -13,11 +13,39 @@ import (
 	"github.com/ARM-software/golang-utils/utils/reflection"
 )
 
-// FilepathStem returns  the final path component, without its suffix.
+// FilepathStem returns  the final path component, without its suffix. It's similar to `stem` in python's [pathlib](https://docs.python.org/3/library/pathlib.html#pathlib.PurePath.stem)
 func FilepathStem(fp string) string {
 	return strings.TrimSuffix(filepath.Base(fp), filepath.Ext(fp))
 }
 
+// FilepathParents returns a list of to the logical ancestors of the path and it's similar to `parents` in python's [pathlib](https://docs.python.org/3/library/pathlib.html#pathlib.PurePath.parents)
+func FilepathParents(fp string) []string {
+	return FilePathParentsOnFilesystem(GetGlobalFileSystem(), fp)
+}
+
+// FilePathParentsOnFilesystem is similar to FilepathParents but with the ability to be applied to a particular filesystem.
+func FilePathParentsOnFilesystem(fs FS, fp string) (parents []string) {
+	cleanFp := filepath.Clean(fp)
+	elements := strings.Split(cleanFp, string(fs.PathSeparator()))
+	if len(elements) <= 1 {
+		return
+	}
+	path := elements[0]
+	if path == "" {
+		elements = elements[1:]
+		if len(elements) <= 1 {
+			return
+		}
+		path = elements[0]
+	}
+	parents = append(parents, path)
+	for i := 1; i < len(elements)-1; i++ {
+		path = strings.Join([]string{path, elements[i]}, string(fs.PathSeparator()))
+		parents = append(parents, path)
+	}
+	return
+}
+
 // FileTreeDepth returns the depth of a file in a tree starting from root
 func FileTreeDepth(fs FS, root, filePath string) (depth int64, err error) {
 	if reflection.IsEmpty(filePath) {
diff --git a/utils/filesystem/filepath_test.go b/utils/filesystem/filepath_test.go
index 06becf2481..ae0d94ac66 100644
--- a/utils/filesystem/filepath_test.go
+++ b/utils/filesystem/filepath_test.go
@@ -12,6 +12,7 @@ import (
 
 	"github.com/ARM-software/golang-utils/utils/commonerrors"
 	"github.com/ARM-software/golang-utils/utils/commonerrors/errortest"
+	"github.com/ARM-software/golang-utils/utils/platform"
 )
 
 func TestFilepathStem(t *testing.T) {
@@ -29,6 +30,61 @@ func TestFilepathStem(t *testing.T) {
 	})
 }
 
+func TestFilepathParents(t *testing.T) {
+	type PathTest struct {
+		path            string
+		expectedParents []string
+	}
+	tests := []PathTest{
+		{},
+		{
+			path:            "                             ",
+			expectedParents: nil,
+		},
+		{
+			path:            "/",
+			expectedParents: nil,
+		},
+		{
+			path:            ".",
+			expectedParents: nil,
+		},
+		{
+			path:            "./",
+			expectedParents: nil,
+		},
+		{
+			path:            "./blah",
+			expectedParents: nil,
+		},
+		{
+			path:            filepath.Join("a", "great", "fake", "path", "blah"),
+			expectedParents: []string{"a", filepath.Join("a", "great"), filepath.Join("a", "great", "fake"), filepath.Join("a", "great", "fake", "path")},
+		},
+		{
+			path:            "/foo/bar/setup.py",
+			expectedParents: []string{`foo`, filepath.Join(`foo`, `bar`)},
+		},
+	}
+
+	if platform.IsWindows() {
+		tests = append(tests, PathTest{
+			path:            "C:/foo/bar/setup.py",
+			expectedParents: []string{"C:", filepath.Join(`C:`, `\foo`), filepath.Join(`C:`, `\foo`, `bar`)},
+		})
+	} else {
+		tests = append(tests, PathTest{
+			path:            "C:/foo/bar/setup.py",
+			expectedParents: []string{"C:", filepath.Join(`C:`, `foo`), filepath.Join(`C:`, `foo`, `bar`)},
+		})
+	}
+	for _, tt := range tests {
+		t.Run(tt.path, func(t *testing.T) {
+			assert.ElementsMatch(t, tt.expectedParents, FilepathParents(tt.path))
+		})
+	}
+}
+
 func TestFileTreeDepth(t *testing.T) {
 	random := fmt.Sprintf("%v %v %v", faker.Name(), faker.Name(), faker.Name())
 	complexRandom := fmt.Sprintf("%v&#~@£*-_()^+!%v %v", faker.Name(), faker.Name(), faker.Name())