complete restructure

vibe_bot/tests/test_textutil.py

@@ -0,0 +1,109 @@
+"""Tests for the textutil module."""
+
+from __future__ import annotations
+
+import pytest
+
+from vibe_bot.textutil import split_message
+
+
+def test_split_message_empty() -> None:
+    assert split_message("") == []
+
+
+def test_split_message_short_text_single_chunk() -> None:
+    assert split_message("hello") == ["hello"]
+
+
+def test_split_message_exact_limit() -> None:
+    text = "a" * 1900
+    chunks = split_message(text)
+    assert chunks == [text]
+    assert len(chunks) == 1
+
+
+def test_split_message_just_over_limit_no_newline() -> None:
+    text = "a" * 1901
+    chunks = split_message(text)
+    assert "".join(chunks) == text
+    assert all(len(c) <= 1900 for c in chunks)
+    assert chunks == ["a" * 1900, "a"]
+
+
+def test_split_message_no_newlines_long() -> None:
+    text = "x" * 5000
+    chunks = split_message(text)
+    assert "".join(chunks) == text
+    assert all(len(c) <= 1900 for c in chunks)
+
+
+def test_split_message_respects_newlines() -> None:
+    # Many short lines spanning several chunks: boundaries fall on newlines.
+    text = "\n".join(f"line {i}" for i in range(1, 501))
+    chunks = split_message(text)
+    assert "".join(chunks) == text
+    assert all(len(c) <= 1900 for c in chunks)
+    assert len(chunks) > 1
+    # Every chunk except the last ends on a newline (split at a line boundary).
+    for chunk in chunks[:-1]:
+        assert chunk.endswith("\n")
+
+
+def test_split_message_long_line_hard_split() -> None:
+    # A single line longer than the limit must be hard-split.
+    text = "a" * 5000 + "\n" + "short"
+    chunks = split_message(text)
+    assert "".join(chunks) == text
+    assert all(len(c) <= 1900 for c in chunks)
+
+
+def test_split_message_emoji_round_trip() -> None:
+    # Multi-codepoint emoji at split boundaries must not corrupt on join.
+    text = "hello 🌍 world 👨‍👩‍👧‍👦 end " * 500
+    for limit in (1, 10, 100, 1900):
+        chunks = split_message(text, limit)
+        assert "".join(chunks) == text
+        assert all(len(c) <= limit for c in chunks)
+
+
+def test_split_message_property_round_trip_corpus() -> None:
+    corpus = [
+        "",
+        "a",
+        "a" * 1900,
+        "a" * 1901,
+        "line1\nline2\nline3",
+        "para one\n\npara two\n\npara three",
+        "no newline " * 1000,
+        "emoji 🎉 " * 1000,
+        "👨‍👩‍👧‍👦" * 2000,
+        "mixed 🌍 text and 日本語 and emoji 🎊 here",
+        # NFD combining marks (e + U+0301, a + U+0308) straddle split points.
+        "cafe\u0301 " * 1000,
+        "a\u0308\u0301 b\u0327\u0301 c\u0308 " * 1000,
+        # Code spans with backticks and spaces.
+        "`inline code` and `x = 1` spans " * 500,
+        "``double backtick`` `single` " * 500,
+    ]
+    for text in corpus:
+        for limit in (1, 5, 100, 1900):
+            chunks = split_message(text, limit)
+            assert "".join(chunks) == text, f"round-trip failed for limit={limit}"
+            assert all(len(c) <= limit for c in chunks)
+
+
+def test_split_message_exact_multiple_of_limit() -> None:
+    """Input that is an exact multiple of the limit splits into full chunks."""
+    for limit in (1, 5, 100, 1900):
+        text = "z" * (limit * 4)
+        chunks = split_message(text, limit)
+        assert "".join(chunks) == text
+        assert len(chunks) == 4
+        assert all(len(c) == limit for c in chunks)
+
+
+def test_split_message_limit_must_be_positive() -> None:
+    with pytest.raises(ValueError):
+        split_message("hello", 0)
+    with pytest.raises(ValueError):
+        split_message("hello", -5)