Simplify test suite to pytest unit scaffolding

tests/unit/__init__.py

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+"""Unit test package for PeakRDL BusDecoder."""

tests/unit/conftest.py

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+"""Pytest fixtures for unit tests."""
+
+from __future__ import annotations
+
+from pathlib import Path
+from tempfile import NamedTemporaryFile
+from typing import Iterable, Mapping, Optional
+
+import pytest
+from systemrdl import RDLCompileError, RDLCompiler
+
+
+@pytest.fixture
+def compile_rdl(tmp_path: Path):
+    """Compile inline SystemRDL source and return the elaborated root node.
+
+    Parameters
+    ----------
+    tmp_path:
+        Temporary directory provided by pytest.
+    """
+
+    def _compile(
+        source: str,
+        *,
+        top: Optional[str] = None,
+        defines: Optional[Mapping[str, object]] = None,
+        include_paths: Optional[Iterable[Path | str]] = None,
+    ):
+        compiler = RDLCompiler()
+
+        for key, value in (defines or {}).items():
+            compiler.define(key, value)
+
+        for include_path in include_paths or ():
+            compiler.add_include_path(str(include_path))
+
+        with NamedTemporaryFile("w", suffix=".rdl", dir=tmp_path) as tmp_file:
+            tmp_file.write(source)
+            tmp_file.flush()
+
+            try:
+                compiler.compile_file(tmp_file.name)
+                if top is not None:
+                    return compiler.elaborate(top)
+                return compiler.elaborate()
+            except RDLCompileError:
+                compiler.print_messages()
+                raise
+
+    return _compile