Fixes a bug where file listing would fail if there is a relative syml…

…ink.

This will now resolve relative symlinks based on the parent directory of the symlink.

Ex: /foo/bar/my-link -> my-file
Then: it resolves my-link to /foo/bar/my-file
Signed-off-by: Daniel Mikusa <dmikusa@vmware.com>

sherpa/file_listing.go

@@ -162,12 +162,15 @@ func process(entry FileEntry) (FileEntry, error) {
 	return entry, nil
 }
 
-func isSymlinkToDir(root string, f fs.FileInfo) (bool, error) {
+func isSymlinkToDir(symlink string, f fs.FileInfo) (bool, error) {
 	if f.Mode().Type() == fs.ModeSymlink {
-		// rawPath := filepath.Join(root, f.Name())
-		path, err := os.Readlink(root)
+		path, err := os.Readlink(symlink)
 		if err != nil {
-			return false, fmt.Errorf("unable to read symlink %s\n%w", root, err)
+			return false, fmt.Errorf("unable to read symlink %s\n%w", symlink, err)
+		}
+
+		if !filepath.IsAbs(path) {
+			path = filepath.Join(filepath.Dir(symlink), path)
 		}
 
 		stat, err := os.Stat(path)

sherpa/file_listing_test.go

@@ -65,17 +65,19 @@ func testFileListing(t *testing.T, context spec.G, it spec.S) {
 		Expect(ioutil.WriteFile(filepath.Join(path, "test-directory", "bravo.txt"), []byte{2}, 0644)).To(Succeed())
 		Expect(os.Symlink(filepath.Join(path, "test-directory"), filepath.Join(path, "symlink-test-dir")))
 		Expect(os.Symlink(filepath.Join(path, "test-directory", "bravo.txt"), filepath.Join(path, "symlink-bravo.txt")))
+		Expect(os.Symlink("alpha.txt", filepath.Join(path, "symlink-relative.txt")))
 
 		e, err := sherpa.NewFileListing(path)
 		Expect(err).NotTo(HaveOccurred())
 
-		Expect(e).To(HaveLen(5))
+		Expect(e).To(HaveLen(6))
 		Expect(e[0].Path).To(HaveSuffix("alpha.txt"))
 		Expect(e[1].Path).To(HaveSuffix("symlink-bravo.txt"))
-		Expect(e[2].Path).To(HaveSuffix("symlink-test-dir"))
-		Expect(e[3].Path).To(HaveSuffix("test-directory"))
-		Expect(e[4].Path).To(HaveSuffix("bravo.txt"))
-		Expect(e[1].SHA256).To(Equal(e[4].SHA256)) // symlink to file should have hash of target file
+		Expect(e[2].Path).To(HaveSuffix("symlink-relative.txt"))
+		Expect(e[3].Path).To(HaveSuffix("symlink-test-dir"))
+		Expect(e[4].Path).To(HaveSuffix("test-directory"))
+		Expect(e[5].Path).To(HaveSuffix("bravo.txt"))
+		Expect(e[1].SHA256).To(Equal(e[5].SHA256)) // symlink to file should have hash of target file
 	})
 
 	it("create listing and get SHA256", func() {