Add parse_rv to extract command value from RV file. Use this to get the RunName in run function to fix the overwrite logic.

Author: huard

CHANGELOG.rst

@@ -5,6 +5,10 @@ Changelog
 v0.18.3 (unreleased)
 --------------------
 
+New features
+^^^^^^^^^^^^
+* Added `parsers.parse_rv` to extract a Command value from an RV file.
+
 Bug fixes
 ^^^^^^^^^
 * Fixed bug affecting `GriddedForcing`, where `station_idx` in the call to ``nc_specs`` was set to ``1`` instead of ``None``. (PR #501)

src/ravenpy/config/parsers.py

@@ -10,6 +10,26 @@
 from .conventions import RAVEN_OUTPUT_FMT
 
 
+def parse_rv(rv: str, command: str) -> str:
+    """Parse an RV file to find the value of a Command (one liner).
+
+    Parameters
+    ----------
+    rv : str
+        The Raven command string, e.g. "RunName".
+    command : str
+        Valid Raven command.
+
+    Returns
+    -------
+    str:
+        Command value. None if not found.
+    """
+    pat = re.compile(rf":{command}\s+(.+)")
+    if match := re.search(pat, rv):
+        return match.groups()[0]
+
+
 def parse_diagnostics(fn: Path):
     """Return dictionary of performance metrics."""
     import csv

src/ravenpy/ravenpy.py

@@ -64,10 +64,6 @@ def run(self, overwrite: bool = False) -> "OutputReader":
         overwrite : bool
             If True, overwrite existing files.
         """
-        if not (self.workdir / f"{self.modelname}.rvi").exists():
-            # FIXME: No attribute 'write_rv' on Emulator [attribute-error]
-            self.write_rv(overwrite=overwrite)
-
         self._output_path = run(
             self.modelname, self.workdir, "output", overwrite=overwrite
         )
@@ -296,21 +292,26 @@ def run(
     if not outputdir.is_absolute():
         outputdir = (configdir / outputdir).absolute()
 
-    if modelname is None:
-        results = [f for f in outputdir.rglob(f"*.*") if "_" not in f.stem]
-    else:
-        results = [f for f in outputdir.rglob(f"{modelname}_*.*")]
-    if len(results) > 0:
-        if overwrite:
-            for f in results:
-                Path(f).unlink()
-        else:
-            msg = f"Output files already exist in {outputdir}. Use `overwrite=True` to overwrite."
-            raise FileExistsError(msg)
-
     if not outputdir.exists():
         Path(str(outputdir)).mkdir(parents=True)
 
+    # Parse RunName
+    rvi = (configdir / f"{modelname}.rvi").read_text()
+    run_name = parsers.parse_rv(rvi, "RunName") or ""
+
+    # Existing output files with the same :RunName - they would be overwritten
+    files = outputdir.glob(f"{run_name}*.*")
+
+    # Remove existing output files if overwrite is True
+    for f in files:
+        if f.is_file():
+            if overwrite:
+                f.unlink()
+            else:
+                raise FileExistsError(
+                    "Output files using this `modelname` already exist. Use `overwrite=True` to remove them."
+                )
+
     # Launch executable, wait for completion.
     cmd = [RAVEN_EXEC_PATH, modelname, "-o", str(outputdir)]
 

tests/conftest.py

@@ -25,7 +25,7 @@
 )
 
 RAVEN_TESTING_DATA_BRANCH = os.getenv("RAVEN_TESTING_DATA_BRANCH", "master")
-SKIP_TEST_DATA = os.getenv("RAVENPY_SKIP_TEST_DATA")
+SKIP_TEST_DATA = True  # os.getenv("RAVENPY_SKIP_TEST_DATA")
 DEFAULT_CACHE = Path(_default_cache_dir)
 
 

tests/test_emulators.py

@@ -59,11 +59,12 @@ def test_run(numeric_config, tmp_path):
     assert isinstance(out.storage, xr.Dataset)
 
 
-def test_run_overwrite(numeric_config, tmp_path):
+def test_run_overwrite(gr4jcn_config, tmp_path):
     """Test that the emulator actually runs and returns the expected NSE."""
-    name, conf = numeric_config
+    gr4jcn, params = gr4jcn_config
+    gr4jcn = gr4jcn.set_params(params)
 
-    e = Emulator(config=conf, workdir=tmp_path)
+    e = Emulator(config=gr4jcn, workdir=tmp_path)
     e.run()
 
     with pytest.raises(FileExistsError):