Changed stage level arguments to a string

src/opustrainer/trainer.py

@@ -496,7 +496,7 @@ def _load_stage(self, ymldata:dict, basepath:str, stage_name:str, available_data
                 until_dataset=until_dataset_name,
                 until_epoch=until_epoch,
                 modifiers=self._load_modifiers(ymldata[stage_name], basepath) if isinstance(ymldata[stage_name], dict) and 'modifiers' in ymldata[stage_name] else None,
-                arguments=[str(arg) for arg in ymldata[stage_name]['arguments']] if isinstance(ymldata[stage_name], dict) and 'arguments' in ymldata[stage_name] else [],
+                arguments=shlex.split(ymldata[stage_name]['arguments']) if isinstance(ymldata[stage_name], dict) and 'arguments' in ymldata[stage_name] else [],
             )
         except Exception as exc:
             raise CurriculumLoaderError(f"could not complete the parse of stage '{stage_name}': {exc!s}") from exc
@@ -839,9 +839,13 @@ def main(args:argparse.Namespace) -> None:
     # Make trainer listen to `kill -SIGUSR1 $PID` to print dataset progress
     signal.signal(signal.SIGUSR1, lambda signum, handler: print_state(trainer.state()))
 
+    # Trainer is whatever is in config['trainer'], unless you specified it on
+    # the cli. If neither is specified, this will raise an KeyError.
+    model_trainer_cmd = args.trainer or shlex.split(config['trainer'])
+
     while trainer.stage is not None:
         model_trainer = subprocess.Popen(
-            (args.trainer or shlex.split(config['trainer'])) + trainer.stage.arguments,
+            model_trainer_cmd + trainer.stage.arguments,
             stdin=subprocess.PIPE,
             encoding="utf-8",
             preexec_fn=ignore_sigint) # ignore_sigint makes marian ignore Ctrl-C. We'll stop it from here.

tests/test_trainer_cli.py

@@ -54,14 +54,14 @@ def test_early_stopping(self):
 						'clean 1.0',
 						'until clean inf'
 					],
-					'arguments': ['5000']
+					'arguments': '-n 5000'
 				},
 				'mid': {
 					'mix': [
 						'medium 1.0',
 						'until medium inf',
 					],
-					'arguments': ['10000']
+					'arguments': '-n 10000'
 				},
 				'seed': 1111
 		}
@@ -76,7 +76,7 @@ def test_early_stopping(self):
 				'--do-not-resume',
 				'--no-shuffle',
 				'--config', str(Path(tmp) / 'config.yml'),
-				'head', '-n', # plus value for n, per stage
+				'head', # plus value for -n, per stage
 			], stdout=fout, stderr=ferr)
 
 			retval = child.wait(30)
@@ -89,7 +89,7 @@ def test_early_stopping(self):
 			# Assert we got the number of lines we'd expect
 			line_count = sum(1 for _ in fout)
 			expected_line_count = sum(
-				int(config[stage]['arguments'][0])
+				int(config[stage]['arguments'][3:]) # interpret the `-n XXX`
 				for stage in config['stages']
 			)
 			self.assertEqual(line_count, expected_line_count)