1 files changed, 108 insertions, 0 deletions
diff --git a/tools/testing/kunit/kunit_config.py b/tools/testing/kunit/kunit_config.py
new file mode 100644
index 000000000..48b5f34b2
--- /dev/null
+++ b/tools/testing/kunit/kunit_config.py
@@ -0,0 +1,108 @@
+# SPDX-License-Identifier: GPL-2.0
+#
+# Builds a .config from a kunitconfig.
+#
+# Copyright (C) 2019, Google LLC.
+# Author: Felix Guo <felixguoxiuping@gmail.com>
+# Author: Brendan Higgins <brendanhiggins@google.com>
+
+from dataclasses import dataclass
+import re
+from typing import Dict, Iterable, List, Set, Tuple
+
+CONFIG_IS_NOT_SET_PATTERN = r'^# CONFIG_(\w+) is not set$'
+CONFIG_PATTERN = r'^CONFIG_(\w+)=(\S+|".*")$'
+
+@dataclass(frozen=True)
+class KconfigEntry:
+	name: str
+	value: str
+
+	def __str__(self) -> str:
+		if self.value == 'n':
+			return f'# CONFIG_{self.name} is not set'
+		return f'CONFIG_{self.name}={self.value}'
+
+
+class KconfigParseError(Exception):
+	"""Error parsing Kconfig defconfig or .config."""
+
+
+class Kconfig:
+	"""Represents defconfig or .config specified using the Kconfig language."""
+
+	def __init__(self) -> None:
+		self._entries = {}  # type: Dict[str, str]
+
+	def __eq__(self, other) -> bool:
+		if not isinstance(other, self.__class__):
+			return False
+		return self._entries == other._entries
+
+	def __repr__(self) -> str:
+		return ','.join(str(e) for e in self.as_entries())
+
+	def as_entries(self) -> Iterable[KconfigEntry]:
+		for name, value in self._entries.items():
+			yield KconfigEntry(name, value)
+
+	def add_entry(self, name: str, value: str) -> None:
+		self._entries[name] = value
+
+	def is_subset_of(self, other: 'Kconfig') -> bool:
+		for name, value in self._entries.items():
+			b = other._entries.get(name)
+			if b is None:
+				if value == 'n':
+					continue
+				return False
+			if value != b:
+				return False
+		return True
+
+	def conflicting_options(self, other: 'Kconfig') -> List[Tuple[KconfigEntry, KconfigEntry]]:
+		diff = []  # type: List[Tuple[KconfigEntry, KconfigEntry]]
+		for name, value in self._entries.items():
+			b = other._entries.get(name)
+			if b and value != b:
+				pair = (KconfigEntry(name, value), KconfigEntry(name, b))
+				diff.append(pair)
+		return diff
+
+	def merge_in_entries(self, other: 'Kconfig') -> None:
+		for name, value in other._entries.items():
+			self._entries[name] = value
+
+	def write_to_file(self, path: str) -> None:
+		with open(path, 'a+') as f:
+			for e in self.as_entries():
+				f.write(str(e) + '\n')
+
+def parse_file(path: str) -> Kconfig:
+	with open(path, 'r') as f:
+		return parse_from_string(f.read())
+
+def parse_from_string(blob: str) -> Kconfig:
+	"""Parses a string containing Kconfig entries."""
+	kconfig = Kconfig()
+	is_not_set_matcher = re.compile(CONFIG_IS_NOT_SET_PATTERN)
+	config_matcher = re.compile(CONFIG_PATTERN)
+	for line in blob.split('\n'):
+		line = line.strip()
+		if not line:
+			continue
+
+		match = config_matcher.match(line)
+		if match:
+			kconfig.add_entry(match.group(1), match.group(2))
+			continue
+
+		empty_match = is_not_set_matcher.match(line)
+		if empty_match:
+			kconfig.add_entry(empty_match.group(1), 'n')
+			continue
+
+		if line[0] == '#':
+			continue
+		raise KconfigParseError('Failed to parse: ' + line)
+	return kconfig