MIL-009: Executable with PyInstaller

Review record RC-048 (Go, autonomous mode, not independent).

Task: MIL-009#1
Task: MIL-009#2
Task: MIL-009#3
Task: MIL-009#4
Task: MIL-009#5
Task: MIL-009#6
Task: MIL-009#7
Task: MIL-009#8

tests/unit/test_runtime.py

@@ -0,0 +1,45 @@
+"""Tests of the runtime helpers.
+
+@file test_runtime.py
+@brief Checks where resources and the executable are, frozen or from source.
+"""
+
+from pathlib import Path
+
+from flash_card import runtime
+
+BUNDLE = Path("bundle")
+EXECUTABLE = Path("apps") / "flash-card.exe"
+ROOT = Path("project")
+
+
+def test_pick_resource_root_returns_bundle_when_frozen() -> None:
+    assert runtime.pick_resource_root(True, BUNDLE, ROOT) == BUNDLE
+
+
+def test_pick_resource_root_returns_root_when_not_frozen() -> None:
+    assert runtime.pick_resource_root(False, BUNDLE, ROOT) == ROOT
+
+
+def test_pick_resource_root_returns_root_when_bundle_is_unknown() -> None:
+    assert runtime.pick_resource_root(True, None, ROOT) == ROOT
+
+
+def test_pick_executable_dir_returns_executable_folder_when_frozen() -> None:
+    assert runtime.pick_executable_dir(True, EXECUTABLE, ROOT) == EXECUTABLE.parent
+
+
+def test_pick_executable_dir_returns_root_when_not_frozen() -> None:
+    assert runtime.pick_executable_dir(False, EXECUTABLE, ROOT) == ROOT
+
+
+def test_is_frozen_is_false_in_a_test_run() -> None:
+    assert runtime.is_frozen() is False
+
+
+def test_resource_root_is_project_root_in_a_source_run() -> None:
+    assert (runtime.resource_root() / "pyproject.toml").is_file()
+
+
+def test_executable_dir_is_project_root_in_a_source_run() -> None:
+    assert runtime.executable_dir() == runtime.source_root()