ci: Add unit and integration tests

tests/unit/test_utils.py

@@ -0,0 +1,99 @@
+"""Unit tests for docker_agent_sandbox.tools._utils — no Docker required."""
+
+import pytest
+
+from docker_agent_sandbox.tools._utils import (
+    _MAX_OUTPUT_CHARS,
+    _MAX_OUTPUT_LINES,
+    _TRUNCATION_NOTICE,
+    _parent,
+    truncate_output,
+)
+
+
+# ---------------------------------------------------------------------------
+# truncate_output
+# ---------------------------------------------------------------------------
+
+
+def test_truncate_output_short_string_unchanged():
+    assert truncate_output("hello world") == "hello world"
+
+
+def test_truncate_output_empty_string():
+    assert truncate_output("") == ""
+
+
+def test_truncate_output_exactly_at_line_limit():
+    output = "line\n" * _MAX_OUTPUT_LINES
+    assert truncate_output(output) == output
+
+
+def test_truncate_output_one_over_line_limit():
+    output = "line\n" * (_MAX_OUTPUT_LINES + 1)
+    result = truncate_output(output)
+    assert _TRUNCATION_NOTICE in result
+    # 200 "line\n" kept + notice; the 201st "line" must not appear
+    assert result.count("line\n") == _MAX_OUTPUT_LINES
+
+
+def test_truncate_output_line_limit_keeps_first_200():
+    output = "line\n" * 250
+    result = truncate_output(output)
+    assert result.startswith("line\n" * _MAX_OUTPUT_LINES)
+    assert _TRUNCATION_NOTICE in result
+
+
+def test_truncate_output_exactly_at_char_limit():
+    output = "x" * _MAX_OUTPUT_CHARS
+    assert truncate_output(output) == output
+
+
+def test_truncate_output_one_over_char_limit():
+    output = "x" * (_MAX_OUTPUT_CHARS + 1)
+    result = truncate_output(output)
+    assert _TRUNCATION_NOTICE in result
+    # Exactly _MAX_OUTPUT_CHARS x's are kept before the notice
+    assert result.startswith("x" * _MAX_OUTPUT_CHARS)
+    assert result[_MAX_OUTPUT_CHARS] != "x"
+
+
+def test_truncate_output_char_limit_takes_first_20000():
+    output = "x" * 25_000
+    result = truncate_output(output)
+    assert result.startswith("x" * _MAX_OUTPUT_CHARS)
+    assert _TRUNCATION_NOTICE in result
+
+
+def test_truncate_output_line_limit_checked_before_char_limit():
+    # 201 lines of 200 chars each = 201 * 201 = ~40k chars (> char limit too).
+    # Lines are checked first, so only the line-limit truncation notice appears.
+    output = ("x" * 200 + "\n") * 201
+    result = truncate_output(output)
+    assert _TRUNCATION_NOTICE in result
+    # After line truncation the result is 200 * 201 = 40200 chars + notice,
+    # which is still > _MAX_OUTPUT_CHARS, so the char truncation fires too.
+    # Either way the result must be shorter than the input.
+    assert len(result) < len(output)
+
+
+# ---------------------------------------------------------------------------
+# _parent
+# ---------------------------------------------------------------------------
+
+
+@pytest.mark.parametrize(
+    "path, expected",
+    [
+        ("/foo/bar/baz.txt", "/foo/bar"),
+        ("/foo/bar/baz/", "/foo/bar"),   # trailing slash stripped before dirname
+        ("/foo/bar", "/foo"),
+        ("/foo", "/"),
+        ("foo/bar/baz", "foo/bar"),
+        ("foo/bar", "foo"),
+        ("foo", "."),
+        ("", "."),
+    ],
+)
+def test_parent(path, expected):
+    assert _parent(path) == expected