launch: a reason joined after 'The engine could not be installed.' starts with a capital; test

strata_cli/launch/runner.py

@@ -81,6 +81,11 @@ def missing_file(failure: str) -> bool:
     return failure.startswith(("ModuleNotFoundError", "ImportError", "FileNotFoundError"))
 
 
+def capital(text: str) -> str:
+    """A reason that was written to stand alone ("the update feed could not be read: ...") starts the sentence it is joined to with a capital."""
+    return text[:1].upper() + text[1:]
+
+
 class LaunchError(RuntimeError):
     """A step could not be done. `text` says what it means; `next` says what to do."""
 
@@ -615,6 +620,7 @@ class Runner:
                             why = str(res["error"])
                             break
             why = why or (tail[-1] if tail else "")
+            why = capital(why)                         # (joined after a sentence: "the update feed could not be read ..." starts a new one)
             raise LaunchError("The engine could not be installed." + (f" {why}" if why else ""),
                               "Check your internet connection, or point Strata at an update source with --feed, then try again.", 6)
         self.emit("engine", "The engine is installed.", 100)

tests/terminal/test_launch.py

@@ -970,6 +970,12 @@ class FlagsCommand(unittest.TestCase):
         self.assertEqual(code, 0)                                              # the preset's own key
         self.assertTrue(out.strip().startswith("sk-strata-"))
 
+    def test_a_reason_joined_after_a_sentence_starts_with_a_capital(self):
+        from strata_cli.launch.runner import capital
+        self.assertEqual(capital("the update feed could not be read: no route"), "The update feed could not be read: no route")
+        self.assertEqual(capital("Already fine."), "Already fine.")
+        self.assertEqual(capital(""), "")
+
     def test_launch_error_is_one_plain_sentence(self):
         from strata_cli.launch.runner import LaunchError
         with mock.patch.object(Runner, "run", side_effect=LaunchError("The engine could not be installed.", "Check your internet.", 6)):