color difference in versions

Inspired by nala

.gitignore

@@ -1 +1,2 @@
 .idea/
+__pycache__/

diff.py

@@ -0,0 +1,27 @@
+from difflib import SequenceMatcher
+
+COLOR_BLUE = '\033[34m'
+ENDC = '\033[0m'
+
+
+def get_diff(a: str, b: str) -> str:
+    sm = SequenceMatcher(None, a, b)
+    output = []
+    for opcode, a0, a1, b0, b1 in sm.get_opcodes():
+        if opcode == 'equal':
+            output.append(a[a0:a1])
+        elif opcode in ['insert', 'replace']:
+            output.append(COLOR_BLUE + b[b0:b1] + ENDC)
+        elif opcode == 'delete':
+            ...
+            # output.append("<del>" + seqm.a[a0:a1] + "</del>")
+        else:
+            raise RuntimeError("unexpected opcode")
+    return ''.join(output)
+
+
+if __name__ == '__main__':
+    a = "Wort"
+    b = "Woort"
+
+    print(get_diff(a, b))

main.py

@@ -8,6 +8,8 @@ from typing import Union
 from packaging import version
 from packaging.version import Version, InvalidVersion
 
+from diff import get_diff
+
 # https://www.debian.org/doc/debian-policy/ch-controlfields.html#version
 
 SomeVersion = Union[Version]
@@ -86,12 +88,13 @@ for update in UpdateType:
     text += update.value.center(width, "-")
 
     for update in sub_updates:
+        diff_text = get_diff(update.old_version, update.new_version)
         text += (
             f"{update.name:<{max(len(u.name) for u in sub_updates)}}"
             " "
             f"{update.old_version:<{max(len(u.old_version) for u in sub_updates)}}"
             " ➜ "
-            f"{update.new_version:<{max(len(u.old_version) for u in sub_updates)}}"
+            f"{diff_text:<{max(len(u.old_version) for u in sub_updates)}}"
             "\n"
         )