Fix case where DSDA not being set in the config caused a crash.

Also fix the relevant error message's formatting.

dcc/config.py

@@ -15,7 +15,7 @@ class ConfigBase(object):
             self.doom.joinpath(self.config_name)).read()
 
         self._dsda = self._config.get("dsda")
-        if self.dsda is None:
+        if self._dsda is None:
             raise Exception(
                 "required key 'dsda' not set in config "
                 + f"{self.doom.joinpath(self.config_name)}.")
@@ -37,7 +37,7 @@ class ConfigBase(object):
         propname = "_".join(what)
         val = self._config
         for w in what:
-            val = val[w]
+            val = val.get(w)
             if val is None:
                 val = default
                 break

dcc/extract.py

@@ -40,6 +40,6 @@ class Extract(dcc.doom_base.Wad):
                 )
 
         print(
-            "Lump {parsed_args.lump} not found in any wad in "
+            f"Lump {parsed_args.lump} not found in any wad in "
             + f"{parsed_args.wad}"
         )

pyproject.toml

@@ -16,6 +16,9 @@ dependencies = [
     "omgifol (>=0.5.1,<0.6.0)",
     "tomlkit (>=0.13.3,<0.14.0)",
     "wand (>=0.6.13,<0.7.0)",
+    "pytest (>=8.4.2,<9.0.0)",
+    "pillow (>=11.3.0,<12.0.0)",
+    "pytest-mockito (>=0.0.4,<0.0.5)",
 ]
 
 
@@ -31,3 +34,8 @@ dcc = { source = "dcc/main.py", type = "onefile" }
 
 [tool.poetry-pyinstaller-plugin.collect]
 all = ["cliff"]
+
+[tool.pytest.ini_options]
+testpaths = [
+	"tests",
+]