feat(cli): improve multiline previews

tests/cli/test_cli_user_message_preview.py

@@ -0,0 +1,92 @@
+import importlib
+import os
+import sys
+from unittest.mock import MagicMock, patch
+
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), ".."))
+
+
+_cli_mod = None
+
+
+def _make_cli(user_message_preview=None):
+    global _cli_mod
+    clean_config = {
+        "model": {
+            "default": "anthropic/claude-opus-4.6",
+            "base_url": "https://openrouter.ai/api/v1",
+            "provider": "auto",
+        },
+        "display": {
+            "compact": False,
+            "tool_progress": "all",
+            "user_message_preview": user_message_preview or {"first_lines": 2, "last_lines": 2},
+        },
+        "agent": {},
+        "terminal": {"env_type": "local"},
+    }
+    clean_env = {"LLM_MODEL": "", "HERMES_MAX_ITERATIONS": ""}
+    prompt_toolkit_stubs = {
+        "prompt_toolkit": MagicMock(),
+        "prompt_toolkit.history": MagicMock(),
+        "prompt_toolkit.styles": MagicMock(),
+        "prompt_toolkit.patch_stdout": MagicMock(),
+        "prompt_toolkit.application": MagicMock(),
+        "prompt_toolkit.layout": MagicMock(),
+        "prompt_toolkit.layout.processors": MagicMock(),
+        "prompt_toolkit.filters": MagicMock(),
+        "prompt_toolkit.layout.dimension": MagicMock(),
+        "prompt_toolkit.layout.menus": MagicMock(),
+        "prompt_toolkit.widgets": MagicMock(),
+        "prompt_toolkit.key_binding": MagicMock(),
+        "prompt_toolkit.completion": MagicMock(),
+        "prompt_toolkit.formatted_text": MagicMock(),
+        "prompt_toolkit.auto_suggest": MagicMock(),
+    }
+    with patch.dict(sys.modules, prompt_toolkit_stubs), patch.dict("os.environ", clean_env, clear=False):
+        import cli as mod
+
+        mod = importlib.reload(mod)
+        _cli_mod = mod
+        with patch.object(mod, "get_tool_definitions", return_value=[]), patch.dict(mod.__dict__, {"CLI_CONFIG": clean_config}):
+            return mod.HermesCLI()
+
+
+class TestSubmittedUserMessagePreview:
+    def test_default_preview_shows_first_two_lines_and_last_two_lines(self):
+        cli = _make_cli()
+
+        rendered = cli._format_submitted_user_message_preview(
+            "line1\nline2\nline3\nline4\nline5\nline6"
+        )
+
+        assert "line1" in rendered
+        assert "line2" in rendered
+        assert "line5" in rendered
+        assert "line6" in rendered
+        assert "line3" not in rendered
+        assert "line4" not in rendered
+        assert "(+2 more lines)" in rendered
+
+    def test_preview_can_hide_last_lines(self):
+        cli = _make_cli({"first_lines": 2, "last_lines": 0})
+
+        rendered = cli._format_submitted_user_message_preview(
+            "line1\nline2\nline3\nline4\nline5\nline6"
+        )
+
+        assert "line1" in rendered
+        assert "line2" in rendered
+        assert "line5" not in rendered
+        assert "line6" not in rendered
+        assert "(+4 more lines)" in rendered
+
+    def test_invalid_first_lines_value_falls_back_to_one(self):
+        cli = _make_cli({"first_lines": 0, "last_lines": 2})
+
+        rendered = cli._format_submitted_user_message_preview("line1\nline2\nline3\nline4")
+
+        assert "line1" in rendered
+        assert "line3" in rendered
+        assert "line4" in rendered
+        assert "(+1 more line)" in rendered