Add tests for `extract_content_string` error handling in `cli/main.py`

Co-authored-by: aguzererler <6199053+aguzererler@users.noreply.github.com>

tests/cli/test_main.py

@@ -0,0 +1,27 @@
+import pytest
+from cli.main import extract_content_string
+
+def test_extract_content_string_empty():
+    assert extract_content_string(None) is None
+    assert extract_content_string("") is None
+    assert extract_content_string("   ") is None
+
+def test_extract_content_string_valid_eval():
+    assert extract_content_string("[]") is None
+    assert extract_content_string("{}") is None
+    assert extract_content_string('""') is None
+
+def test_extract_content_string_invalid_eval_valueerror():
+    # simulating ValueError in literal_eval
+    assert extract_content_string("not_a_valid_python_literal") == "not_a_valid_python_literal"
+
+def test_extract_content_string_invalid_eval_syntaxerror():
+    # simulating SyntaxError in literal_eval
+    assert extract_content_string("{[}") == "{[}"
+
+def test_extract_content_string_dict():
+    assert extract_content_string({"text": "hello"}) == "hello"
+    assert extract_content_string({"text": "   "}) is None
+
+def test_extract_content_string_list():
+    assert extract_content_string([{"type": "text", "text": "hello"}, " world"]) == "hello world"