test: fix the four failures in the unit suite

Both pairs were test bugs, not defects in the code under test.

tests/test_opencode_binary.py -- resolve_opencode_argv() returns str(Path), so
the expected value has to be spelled the same way: str(Path("/mgd/opencode"))
is "/mgd/opencode" on POSIX and "\mgd\opencode" on Windows. The POSIX form was
hard-coded, so `test_managed_present_wins` and `test_download_when_no_path`
failed on Windows only. Compare against str(Path(...)).

tests/general/test_four_way_standalone.py -- `set_hp` refuses to guess when the
process holds more than one hyperparam set ("Multiple hyperparam sets present;
provide hp_name explicitly"), and the ledger is global: the sets registered by
the other levels in this file, and by any module that ran earlier in the same
process, are still there. So the two set_hp tests passed or failed depending on
what had run before them. They now name their set via resolve_hp_name(),
exactly as test_hp_lists_and_shows in the same file already does for `hp` --
and which its own comment explains was added for this reason.

Full suite as CI runs it (pytest ./tests -m "not scale"): 1901 passed,
145 skipped, 17 deselected.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

Author: guillaume-byte

tests/general/test_four_way_standalone.py

@@ -504,15 +504,22 @@ def test_hp_lists_and_shows(self):
         self.assertEqual(shown["name"], name)
         self.assertEqual(shown["hyperparams"]["experiment_name"], "standalone_config")
 
+    # `set_hp` refuses to guess when the process holds more than one
+    # hyperparam set ("Multiple hyperparam sets present; provide hp_name
+    # explicitly"), and the ledger is global: the sets registered by the other
+    # levels in this file (and by any test module that ran earlier in the same
+    # process) are still there. Name the set, exactly as test_hp_lists_and_shows
+    # already does for `hp` -- the alternative, asserting on whichever set the
+    # CLI happens to pick, is what made these two order-dependent.
     def test_set_hp_updates_the_live_config(self):
-        answer = self.cli("set_hp optimizer.lr 0.0005")
+        answer = self.cli(f"set_hp {resolve_hp_name()} optimizer.lr 0.0005")
         self.assertTrue(answer["ok"], answer)
         self.assertEqual(answer["key"], "optimizer.lr")
         self.assertEqual(answer["value"], 0.0005)
         self.assertEqual(self.hp["optimizer"]["lr"], 0.0005)
 
     def test_set_hp_updates_a_nested_data_key(self):
-        answer = self.cli("set_hp data.train_loader.batch_size 32")
+        answer = self.cli(f"set_hp {resolve_hp_name()} data.train_loader.batch_size 32")
         self.assertTrue(answer["ok"], answer)
         self.assertEqual(self.hp["data"]["train_loader"]["batch_size"], 32)
 

tests/test_opencode_binary.py

@@ -218,11 +218,17 @@ class ResolverPrecedenceTests(unittest.TestCase):
     """opencode_process.resolve_opencode_argv order:
     managed-present -> PATH -> managed-download -> npx -> None."""
 
+    # resolve_opencode_argv returns str(Path), so the expected value has to be
+    # spelled the same way: str(Path("/mgd/opencode")) is "/mgd/opencode" on
+    # POSIX and "\\mgd\\opencode" on Windows. Hard-coding the POSIX form made
+    # these two fail on Windows only, for no reason in the code under test.
+    MANAGED = str(Path("/mgd/opencode"))
+
     def test_managed_present_wins(self):
         with patch.object(opencode_process.opencode_binary, "find_managed_binary",
                           return_value=Path("/mgd/opencode")), \
                 patch.object(opencode_process.shutil, "which", return_value="/usr/bin/opencode"):
-            self.assertEqual(opencode_process.resolve_opencode_argv(), ["/mgd/opencode"])
+            self.assertEqual(opencode_process.resolve_opencode_argv(), [self.MANAGED])
 
     def test_path_used_before_download(self):
         with patch.object(opencode_process.opencode_binary, "find_managed_binary", return_value=None), \
@@ -237,7 +243,7 @@ def test_download_when_no_path(self):
                 patch.object(opencode_process.opencode_binary, "ensure_managed_binary",
                              return_value=Path("/mgd/opencode")), \
                 patch.object(opencode_process.shutil, "which", return_value=None):
-            self.assertEqual(opencode_process.resolve_opencode_argv(), ["/mgd/opencode"])
+            self.assertEqual(opencode_process.resolve_opencode_argv(), [self.MANAGED])
 
     def test_npx_last_resort(self):
         def which(name):