Merge pull request #4864 from jestabro/util-file-compare

T8031: file comparison in boolean check unsaved_commits should ignore blank lines

2 files changed, 29 insertions, 1 deletions

diff --git a/python/vyos/config_mgmt.py b/python/vyos/config_mgmt.py
index 6bc9ff333..1ce397136 100644
--- a/python/vyos/config_mgmt.py
+++ b/python/vyos/config_mgmt.py
@@ -48,6 +48,7 @@ from vyos.utils.process import is_systemd_service_active
 from vyos.utils.process import rc_cmd
 from vyos.defaults import DEFAULT_COMMIT_CONFIRM_MINUTES
 from vyos.component_version import append_system_version
+from vyos.utils.file import file_compare
 
 SAVE_CONFIG = '/usr/libexec/vyos/vyos-save-config.py'
 config_json = '/run/vyatta/config/config.json'
@@ -97,7 +98,7 @@ def unsaved_commits(allow_missing_config=False) -> bool:
         return True
     tmp_save = '/tmp/config.running'
     save_config(tmp_save)
-    ret = not cmp(tmp_save, config_file, shallow=False)
+    ret = not file_compare(tmp_save, config_file)
     os.unlink(tmp_save)
     return ret
 
diff --git a/python/vyos/utils/file.py b/python/vyos/utils/file.py
index 98d88d9e4..6708ade2d 100644
--- a/python/vyos/utils/file.py
+++ b/python/vyos/utils/file.py
@@ -312,3 +312,30 @@ def move_recursive(src: str, dst: str, overwrite=False):
 
     copy_recursive(src, dst, overwrite=overwrite)
     shutil.rmtree(src)
+
+
+def file_compare(file1: str, file2: str) -> bool:
+    """
+    Compare two files modulo blank lines, leading/trailing whitespace, final
+    newline.
+
+    Returns:
+        bool: True if files are equivalent in the sense above.
+
+    """
+
+    def non_empty(line):
+        return bool(line.strip())
+
+    with open(file1) as f1, open(file2) as f2:
+        it1 = filter(non_empty, f1)
+        it2 = filter(non_empty, f2)
+
+        try:
+            for l1, l2 in zip(it1, it2, strict=True):
+                if l1.strip() != l2.strip():
+                    return False
+        except ValueError:
+            return False
+
+        return True