Add additional coverage ahead of Path conversion (#10723)

tests/unit_tests/build_gen/test_platformio.py

@@ -0,0 +1,188 @@
+"""Tests for esphome.build_gen.platformio module."""
+
+from __future__ import annotations
+
+from collections.abc import Generator
+from pathlib import Path
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from esphome.build_gen import platformio
+from esphome.core import CORE
+
+
+@pytest.fixture
+def mock_update_storage_json() -> Generator[MagicMock]:
+    """Mock update_storage_json for all tests."""
+    with patch("esphome.build_gen.platformio.update_storage_json") as mock:
+        yield mock
+
+
+@pytest.fixture
+def mock_write_file_if_changed() -> Generator[MagicMock]:
+    """Mock write_file_if_changed for tests."""
+    with patch("esphome.build_gen.platformio.write_file_if_changed") as mock:
+        yield mock
+
+
+def test_write_ini_creates_new_file(
+    tmp_path: Path, mock_update_storage_json: MagicMock
+) -> None:
+    """Test write_ini creates a new platformio.ini file."""
+    CORE.build_path = str(tmp_path)
+
+    content = """
+[env:test]
+platform = espressif32
+board = esp32dev
+framework = arduino
+"""
+
+    platformio.write_ini(content)
+
+    ini_file = tmp_path / "platformio.ini"
+    assert ini_file.exists()
+
+    file_content = ini_file.read_text()
+    assert content in file_content
+    assert platformio.INI_AUTO_GENERATE_BEGIN in file_content
+    assert platformio.INI_AUTO_GENERATE_END in file_content
+
+
+def test_write_ini_updates_existing_file(
+    tmp_path: Path, mock_update_storage_json: MagicMock
+) -> None:
+    """Test write_ini updates existing platformio.ini file."""
+    CORE.build_path = str(tmp_path)
+
+    # Create existing file with custom content
+    ini_file = tmp_path / "platformio.ini"
+    existing_content = f"""
+; Custom header
+[platformio]
+default_envs = test
+
+{platformio.INI_AUTO_GENERATE_BEGIN}
+; Old auto-generated content
+[env:old]
+platform = old
+{platformio.INI_AUTO_GENERATE_END}
+
+; Custom footer
+"""
+    ini_file.write_text(existing_content)
+
+    # New content to write
+    new_content = """
+[env:test]
+platform = espressif32
+board = esp32dev
+framework = arduino
+"""
+
+    platformio.write_ini(new_content)
+
+    file_content = ini_file.read_text()
+
+    # Check that custom parts are preserved
+    assert "; Custom header" in file_content
+    assert "[platformio]" in file_content
+    assert "default_envs = test" in file_content
+    assert "; Custom footer" in file_content
+
+    # Check that new content replaced old auto-generated content
+    assert new_content in file_content
+    assert "[env:old]" not in file_content
+    assert "platform = old" not in file_content
+
+
+def test_write_ini_preserves_custom_sections(
+    tmp_path: Path, mock_update_storage_json: MagicMock
+) -> None:
+    """Test write_ini preserves custom sections outside auto-generate markers."""
+    CORE.build_path = str(tmp_path)
+
+    # Create existing file with multiple custom sections
+    ini_file = tmp_path / "platformio.ini"
+    existing_content = f"""
+[platformio]
+src_dir = .
+include_dir = .
+
+[common]
+lib_deps =
+    Wire
+    SPI
+
+{platformio.INI_AUTO_GENERATE_BEGIN}
+[env:old]
+platform = old
+{platformio.INI_AUTO_GENERATE_END}
+
+[env:custom]
+upload_speed = 921600
+monitor_speed = 115200
+"""
+    ini_file.write_text(existing_content)
+
+    new_content = "[env:auto]\nplatform = new"
+
+    platformio.write_ini(new_content)
+
+    file_content = ini_file.read_text()
+
+    # All custom sections should be preserved
+    assert "[platformio]" in file_content
+    assert "src_dir = ." in file_content
+    assert "[common]" in file_content
+    assert "lib_deps" in file_content
+    assert "[env:custom]" in file_content
+    assert "upload_speed = 921600" in file_content
+
+    # New auto-generated content should replace old
+    assert "[env:auto]" in file_content
+    assert "platform = new" in file_content
+    assert "[env:old]" not in file_content
+
+
+def test_write_ini_no_change_when_content_same(
+    tmp_path: Path,
+    mock_update_storage_json: MagicMock,
+    mock_write_file_if_changed: MagicMock,
+) -> None:
+    """Test write_ini doesn't rewrite file when content is unchanged."""
+    CORE.build_path = str(tmp_path)
+
+    content = "[env:test]\nplatform = esp32"
+    full_content = (
+        f"{platformio.INI_BASE_FORMAT[0]}"
+        f"{platformio.INI_AUTO_GENERATE_BEGIN}\n"
+        f"{content}"
+        f"{platformio.INI_AUTO_GENERATE_END}"
+        f"{platformio.INI_BASE_FORMAT[1]}"
+    )
+
+    ini_file = tmp_path / "platformio.ini"
+    ini_file.write_text(full_content)
+
+    mock_write_file_if_changed.return_value = False  # Indicate no change
+    platformio.write_ini(content)
+
+    # write_file_if_changed should be called with the same content
+    mock_write_file_if_changed.assert_called_once()
+    call_args = mock_write_file_if_changed.call_args[0]
+    assert call_args[0] == str(ini_file)
+    assert content in call_args[1]
+
+
+def test_write_ini_calls_update_storage_json(
+    tmp_path: Path, mock_update_storage_json: MagicMock
+) -> None:
+    """Test write_ini calls update_storage_json."""
+    CORE.build_path = str(tmp_path)
+
+    content = "[env:test]\nplatform = esp32"
+
+    platformio.write_ini(content)
+    mock_update_storage_json.assert_called_once()