fix(cli): don't crash on redirected output with a legacy code page

concore_cli/cli.py

@@ -21,7 +21,10 @@
 @click.group()
 @click.version_option(version=__version__, prog_name="concore")
 def cli():
-    pass
+    # Legacy code pages (e.g. cp1252 when output is redirected on Windows) can't
+    # encode symbols like the check mark; replace them instead of crashing.
+    if hasattr(sys.stdout, "reconfigure"):
+        sys.stdout.reconfigure(errors="replace")
 
 
 @cli.command()

tests/test_cli.py

@@ -882,6 +882,22 @@ def test_build_command_shared_source_specialization_merges_edge_params(self):
             self.assertIn("PORT_NAME_B_C", content)
             self.assertIn("PORT_B_C", content)
 
+    def test_cli_redirected_output_with_legacy_encoding(self):
+        env = dict(os.environ, PYTHONIOENCODING="cp1252")
+        repo_root = str(Path(__file__).resolve().parent.parent)
+        env["PYTHONPATH"] = repo_root + os.pathsep + env.get("PYTHONPATH", "")
+        result = subprocess.run(
+            [sys.executable, "-c", "from concore_cli.cli import cli; cli()"]
+            + ["init", "demo"],
+            cwd=self.temp_dir,
+            env=env,
+            stdin=subprocess.DEVNULL,
+            capture_output=True,
+            timeout=60,
+        )
+        self.assertEqual(result.returncode, 0, result.stderr.decode(errors="replace"))
+        self.assertTrue((Path(self.temp_dir) / "demo" / "workflow.graphml").exists())
+
     def test_build_command_existing_output(self):
         with self.runner.isolated_filesystem(temp_dir=self.temp_dir):
             result = self.runner.invoke(cli, ["init", "test-project"])