From c959f14172cef9fee564d179ff71d20afd6f7884 Mon Sep 17 00:00:00 2001
From: Daniel-I-Am <djdecloet@gmail.com>
Date: Mon, 27 Dec 2021 16:39:52 +0100
Subject: [PATCH] Optimize things that need to run if already correct

---
 run.py | 36 ++++++++++++++++++++++++------------
 1 file changed, 24 insertions(+), 12 deletions(-)

diff --git a/run.py b/run.py
index 1a7a9bc..4496c43 100755
--- a/run.py
+++ b/run.py
@@ -91,21 +91,27 @@ def convert_template(env, template, key_value_store, out):
     if not os.path.isdir(out_dir_name):
         dryrun_safe_mkdir(out_dir_name)
 
-    if os.path.isfile(out) and not args.force:
-        if args.diff:
-            with open(out) as file:
-                current = file.read()
+    if os.path.isfile(out):
+        if is_content_different(out, rendered):
+            if args.diff:
+                with open(out) as file:
+                    current = file.read()
 
-            for line in difflib.unified_diff(current.split('\n'), rendered.split('\n'), fromfile=out, tofile=out+'.new', lineterm=''):
-                print(line, file=sys.stderr)
+                for line in difflib.unified_diff(current.split('\n'), rendered.split('\n'), fromfile=out, tofile=out+'.new', lineterm=''):
+                    print(line, file=sys.stderr)
 
-        if not args.force:
-            print(f"File `{out}` already exists, will not overwrite. Rerun with `-f` to force overwriting existing files.", file=sys.stderr)
-            return
+            if not args.force:
+                print(f"File `{out}` already exists, will not overwrite. Rerun with `-f` to force overwriting existing files.", file=sys.stderr)
+                return
 
-    dryrun_safe_write(out, rendered)
-    if template_permissions != default_permissions:
-        dryrun_safe_chmod(out, template_permissions)
+            dryrun_safe_write(out, rendered)
+
+            if template_permissions != default_permissions:
+                dryrun_safe_chmod(out, template_permissions)
+        else:
+            current_permissions = os.stat(out).st_mode & 0o777
+            if template_permissions != current_permissions:
+                dryrun_safe_chmod(out, template_permissions)
 
     if args.link:
         first_line = source.split('\n')[0]
@@ -135,6 +141,12 @@ def create_symlink(source, destination):
 
     dryrun_safe_create_symlink(source, destination)
 
+def is_content_different(file_location, test_content):
+    with open(file_location) as file:
+        content = file.read()
+
+    return content != test_content
+
 def get_current_umask():
     current_umask = os.umask(0o022)
     os.umask(current_umask)