config: prevent prompting to save config when it has not changed

2 files changed, 15 insertions, 4 deletions

diff --git a/yoyo/config.py b/yoyo/config.py
index 6d05f22..0569a12 100644
--- a/yoyo/config.py
+++ b/yoyo/config.py
@@ -206,3 +206,12 @@ def find_config():
             return path
         d = os.path.dirname(d)
     return None
+
+
+def config_changed(config: ConfigParser, path: str) -> bool:
+    def to_dict(config: ConfigParser):
+        return {k: dict(section.items()) for k, section in config.items()}
+
+    if Path(path).exists():
+        return to_dict(read_config(path)) != to_dict(config)
+    return True
diff --git a/yoyo/scripts/main.py b/yoyo/scripts/main.py
index 7ae7fed..d9894ef 100755
--- a/yoyo/scripts/main.py
+++ b/yoyo/scripts/main.py
@@ -28,6 +28,7 @@ from yoyo.config import CONFIG_FILENAME
 from yoyo.config import find_config
 from yoyo.config import read_config
 from yoyo.config import save_config
+from yoyo.config import config_changed
 from yoyo.config import update_argparser_defaults
 
 verbosity_levels = {
@@ -70,9 +71,8 @@ def parse_args(
     global_args, _ = globalparser.parse_known_args(argv)
 
     # Read the config file and create a dictionary of defaults for argparser
-    config = read_config(
-        (global_args.config or find_config()) if global_args.use_config_file else None
-    )
+    configfile = global_args.config or find_config()
+    config = read_config(configfile if global_args.use_config_file else None)
 
     defaults = {}
     for argname, getter in config_args.items():
@@ -309,7 +309,9 @@ def main(argv=None):
         argparser.error(e.args[0])
 
     if config_is_empty and args.use_config_file and not args.batch_mode:
-        prompt_save_config(config, args.config or CONFIG_FILENAME)
+        config_file = args.config or CONFIG_FILENAME
+        if config_changed(config, config_file):
+            prompt_save_config(config, config_file)
 
     return exitcode