Fix running 'osc build --alternative-project=...' when there's no .osc in the current directory

behave/features/build.feature

@@ -11,3 +11,21 @@ Background:
 Scenario: Run `osc build --just-print-buildroot`
     When I execute osc with args "build --just-print-buildroot"
     Then the exit code is 0
+
+
+Scenario: Run `osc build --alternative-project in an empty directory`
+   Given I set working directory to "{context.osc.temp}"
+    # we point to a spec that doesn't exist, so the command parses the arguments but fails to run the build
+    When I execute osc with args "build --alternative-project=test:factory does-not-exist.spec"
+    Then stdout contains "Building does-not-exist.spec for standard/x86_64"
+     And the exit code is 2
+
+
+Scenario: Run `osc build --alternative-project in an empty directory that has .git in the parent tree`
+   Given I set working directory to "{context.osc.temp}"
+     And I execute "git init -b main"
+     And I create directory "{context.osc.temp}/package"
+    # we point to a spec that doesn't exist, so the command parses the arguments but fails to run the build
+    When I execute osc with args "build --alternative-project=test:factory does-not-exist.spec"
+    Then stdout contains "Building does-not-exist.spec for standard/x86_64"
+     And the exit code is 2

behave/features/steps/common.py

@@ -205,6 +205,12 @@ def step_impl(context):
     raise AssertionError(f"Stderr doesn't match:\n{expected}\n\nActual stderr:\n{found}")
 
 
+@behave.step('I create directory "{path}"')
+def step_impl(context, path):
+    path = path.format(context=context)
+    os.makedirs(path, exist_ok=True)
+
+
 @behave.step('I set working directory to "{path}"')
 def step_impl(context, path):
     path = path.format(context=context)

osc/commandline.py

@@ -7554,7 +7554,9 @@ Please submit there instead, or use --nodevelproject to force direct submission.
         self._debug("arg_repository: ", arg_repository)
         self._debug("arg_descr: ", arg_descr)
 
-        store_obj = osc_store.get_store(".")
+        # we shouldn't make any assumptions if the working copy is valid or not, we simply *try* to read the store and get the metadata from it
+        # the code that calls parse_repoarchdescr() is responsible for checking the store if necessary
+        store_obj = osc_store.get_store(".", check=False)
 
         repositories = []
         # store list of repos for potential offline use
@@ -7907,7 +7909,12 @@ Please submit there instead, or use --nodevelproject to force direct submission.
             except oscerr.NoWorkingCopy:
                 if opts.apiurl and opts.alternative_project:
                     # HACK: ignore invalid working copy and run the build anyway if --alternative-project is specified
-                    store = git_scm.GitStore(Path.cwd(), check=False)
+                    try:
+                        store = git_scm.GitStore(Path.cwd(), check=False)
+                    except oscerr.NoWorkingCopy:
+                        # HACK: if running from an empty directory that has no .git in the parent tree, initialize an empty Store() object
+                        #       this allows running the build with --alternative-project even if .osc doesn't exist at all
+                        store = osc_store.Store(Path.cwd(), check=False)
                 else:
                     raise