test: move vocoder training tests into one file

Gets rid of all the duplication in the tests

TTS/bin/train_vocoder.py

@@ -1,6 +1,8 @@
 import logging
 import os
+import sys
 from dataclasses import dataclass, field
+from typing import Optional
 
 from trainer import Trainer, TrainerArgs
 
@@ -16,7 +18,7 @@ class TrainVocoderArgs(TrainerArgs):
     config_path: str = field(default=None, metadata={"help": "Path to the config file."})
 
 
-def main():
+def main(arg_list: Optional[list[str]] = None):
     """Run `tts` model training directly by a `config.json` file."""
     setup_logger("TTS", level=logging.INFO, screen=True, formatter=ConsoleFormatter())
 
@@ -25,7 +27,7 @@ def main():
     parser = train_args.init_argparse(arg_prefix="")
 
     # override trainer args from comman-line args
-    args, config_overrides = parser.parse_known_args()
+    args, config_overrides = parser.parse_known_args(arg_list)
     train_args.parse_args(args)
 
     # load config.json and register
@@ -75,6 +77,7 @@ def main():
         parse_command_line_args=False,
     )
     trainer.fit()
+    sys.exit(0)
 
 
 if __name__ == "__main__":

tests/vocoder_tests/test_training.py

@@ -0,0 +1,112 @@
+import glob
+import os
+
+import pytest
+
+from tests import run_main
+from TTS.bin.train_vocoder import main
+from TTS.vocoder.configs import (
+    FullbandMelganConfig,
+    HifiganConfig,
+    MelganConfig,
+    MultibandMelganConfig,
+    ParallelWaveganConfig,
+    WavegradConfig,
+    WavernnConfig,
+)
+from TTS.vocoder.models.wavernn import WavernnArgs
+
+GITHUB_ACTIONS = os.getenv("GITHUB_ACTIONS") == "true"
+
+BASE_CONFIG = {
+    "batch_size": 8,
+    "eval_batch_size": 8,
+    "num_loader_workers": 0,
+    "num_eval_loader_workers": 0,
+    "run_eval": True,
+    "test_delay_epochs": -1,
+    "epochs": 1,
+    "seq_len": 8192,
+    "eval_split_size": 1,
+    "print_step": 1,
+    "print_eval": True,
+    "data_path": "tests/data/ljspeech",
+}
+
+DISCRIMINATOR_MODEL_PARAMS = {
+    "base_channels": 16,
+    "max_channels": 64,
+    "downsample_factors": [4, 4, 4],
+}
+
+
+def create_config(config_class, **overrides):
+    params = {**BASE_CONFIG, **overrides}
+    return config_class(**params)
+
+
+def run_train(tmp_path, config):
+    config_path = str(tmp_path / "test_vocoder_config.json")
+    output_path = tmp_path / "train_outputs"
+    config.output_path = output_path
+    config.audio.do_trim_silence = True
+    config.audio.trim_db = 60
+    config.save_json(config_path)
+
+    # Train the model for one epoch
+    run_main(main, ["--config_path", config_path])
+
+    # Find the latest folder
+    continue_path = str(max(glob.glob(os.path.join(output_path, "*/")), key=os.path.getmtime))
+
+    # Restore the model and continue training for one more epoch
+    run_main(main, ["--continue_path", continue_path])
+
+
+def test_train_hifigan(tmp_path):
+    config = create_config(HifiganConfig, seq_len=1024)
+    run_train(tmp_path, config)
+
+
+def test_train_melgan(tmp_path):
+    config = create_config(
+        MelganConfig,
+        batch_size=4,
+        eval_batch_size=4,
+        seq_len=2048,
+        discriminator_model_params=DISCRIMINATOR_MODEL_PARAMS,
+    )
+    run_train(tmp_path, config)
+
+
+def test_train_multiband_melgan(tmp_path):
+    config = create_config(
+        MultibandMelganConfig, steps_to_start_discriminator=1, discriminator_model_params=DISCRIMINATOR_MODEL_PARAMS
+    )
+    run_train(tmp_path, config)
+
+
+def test_train_fullband_melgan(tmp_path):
+    config = create_config(FullbandMelganConfig, discriminator_model_params=DISCRIMINATOR_MODEL_PARAMS)
+    run_train(tmp_path, config)
+
+
+def test_train_parallel_wavegan(tmp_path):
+    config = create_config(ParallelWaveganConfig, batch_size=4, eval_batch_size=4, seq_len=2048)
+    run_train(tmp_path, config)
+
+
+# TODO: Reactivate after improving CI run times
+@pytest.mark.skipif(GITHUB_ACTIONS, reason="Takes ~2h on CI (15min/step vs 8sec/step locally)")
+def test_train_wavegrad(tmp_path):
+    config = create_config(WavegradConfig, test_noise_schedule={"min_val": 1e-6, "max_val": 1e-2, "num_steps": 2})
+    run_train(tmp_path, config)
+
+
+def test_train_wavernn(tmp_path):
+    config = create_config(
+        WavernnConfig,
+        model_args=WavernnArgs(),
+        seq_len=256,  # For shorter test time
+    )
+    run_train(tmp_path, config)