First commit with entire first rendition of the project

tests/test_config.py

@@ -0,0 +1,101 @@
+import os
+import tempfile
+
+import yaml
+
+from spectra.config import DEFAULT_CONFIG, _deep_merge, load_config
+
+
+class TestLoadConfig:
+    def test_defaults_when_no_file(self):
+        cfg = load_config(path="/nonexistent/.spectra/config.yaml")
+        assert cfg["display"]["saturation"] == 0.5
+        assert cfg["display"]["orientation"] == 0
+        assert cfg["unsplash"]["access_key"] == ""
+        assert cfg["schedule"]["interval_hours"] == 1
+
+    def test_load_specific_path(self):
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".yaml", delete=False) as f:
+            yaml.dump({"display": {"saturation": 0.8}}, f)
+            path = f.name
+        try:
+            cfg = load_config(path)
+            assert cfg["display"]["saturation"] == 0.8
+            assert cfg["display"]["orientation"] == 0
+        finally:
+            os.unlink(path)
+
+    def test_missing_path_logs_and_uses_defaults(self):
+        cfg = load_config("/nonexistent/path/config.yaml")
+        assert cfg["display"]["saturation"] == 0.5
+
+    def test_partial_merge_does_not_remove_other_keys(self):
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".yaml", delete=False) as f:
+            yaml.dump({"display": {"saturation": 0.3}}, f)
+            path = f.name
+        try:
+            cfg = load_config(path)
+            assert cfg["display"]["saturation"] == 0.3
+            assert cfg["display"]["resolution"]["width"] == 1600
+            assert cfg["unsplash"]["access_key"] == ""
+        finally:
+            os.unlink(path)
+
+    def test_empty_file_uses_defaults(self):
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".yaml", delete=False) as f:
+            f.write("")
+            path = f.name
+        try:
+            cfg = load_config(path)
+            assert cfg["display"]["saturation"] == 0.5
+        finally:
+            os.unlink(path)
+
+    def test_deep_merge_overrides_nested_key(self):
+        base = {"a": {"b": 1, "c": 2}, "d": 3}
+        override = {"a": {"b": 99}}
+        _deep_merge(base, override)
+        assert base["a"]["b"] == 99
+        assert base["a"]["c"] == 2
+        assert base["d"] == 3
+
+    def test_deep_merge_adds_new_keys(self):
+        base = {"a": 1}
+        override = {"b": 2}
+        _deep_merge(base, override)
+        assert base["a"] == 1
+        assert base["b"] == 2
+
+    def test_deep_merge_overrides_non_dict_with_dict(self):
+        base = {"a": 1}
+        override = {"a": {"b": 2}}
+        _deep_merge(base, override)
+        assert base["a"] == {"b": 2}
+
+    def test_default_config_not_mutated_by_load(self):
+        original_sat = DEFAULT_CONFIG["display"]["saturation"]
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".yaml", delete=False) as f:
+            yaml.dump({"display": {"saturation": 0.9}}, f)
+            path = f.name
+        try:
+            load_config(path)
+            assert DEFAULT_CONFIG["display"]["saturation"] == original_sat
+        finally:
+            os.unlink(path)
+
+    def test_default_config_not_mutated_by_multiple_loads(self):
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".yaml", delete=False) as f:
+            yaml.dump({"unsplash": {"query": "cats"}}, f)
+            path1 = f.name
+        with tempfile.NamedTemporaryFile(mode="w", suffix=".yaml", delete=False) as f:
+            yaml.dump({"unsplash": {"query": "dogs"}}, f)
+            path2 = f.name
+        try:
+            c1 = load_config(path1)
+            c2 = load_config(path2)
+            assert c1["unsplash"]["query"] == "cats"
+            assert c2["unsplash"]["query"] == "dogs"
+            assert DEFAULT_CONFIG["unsplash"]["query"] == ""
+        finally:
+            os.unlink(path1)
+            os.unlink(path2)