buildman: Add helper functions for updating .config files

At present the only straightforward way to write tests that need a
slightly different configuration is to create a new board with its own
configuration. This is cumbersome.

It would be useful if buildman could adjust the configuration of a build
on the fly. In preparation for this, add a utility library which can
modify a .config file according to various parameters passed to it.

Signed-off-by: Simon Glass <sjg@chromium.org>

tools/buildman/test.py

@@ -12,6 +12,7 @@ import unittest
 from buildman import board
 from buildman import bsettings
 from buildman import builder
+from buildman import cfgutil
 from buildman import control
 from buildman import toolchain
 from patman import commit
@@ -624,5 +625,127 @@ class TestBuild(unittest.TestCase):
         expected = set([os.path.join(base_dir, f) for f in to_remove])
         self.assertEqual(expected, result)
 
+    def test_adjust_cfg_nop(self):
+        """check various adjustments of config that are nops"""
+        # enable an enabled CONFIG
+        self.assertEqual(
+            'CONFIG_FRED=y',
+            cfgutil.adjust_cfg_line('CONFIG_FRED=y', {'FRED':'FRED'})[0])
+
+        # disable a disabled CONFIG
+        self.assertEqual(
+            '# CONFIG_FRED is not set',
+            cfgutil.adjust_cfg_line(
+                '# CONFIG_FRED is not set', {'FRED':'~FRED'})[0])
+
+        # use the adjust_cfg_lines() function
+        self.assertEqual(
+            ['CONFIG_FRED=y'],
+            cfgutil.adjust_cfg_lines(['CONFIG_FRED=y'], {'FRED':'FRED'}))
+        self.assertEqual(
+            ['# CONFIG_FRED is not set'],
+            cfgutil.adjust_cfg_lines(['CONFIG_FRED=y'], {'FRED':'~FRED'}))
+
+        # handling an empty line
+        self.assertEqual('#', cfgutil.adjust_cfg_line('#', {'FRED':'~FRED'})[0])
+
+    def test_adjust_cfg(self):
+        """check various adjustments of config"""
+        # disable a CONFIG
+        self.assertEqual(
+            '# CONFIG_FRED is not set',
+            cfgutil.adjust_cfg_line('CONFIG_FRED=1' , {'FRED':'~FRED'})[0])
+
+        # enable a disabled CONFIG
+        self.assertEqual(
+            'CONFIG_FRED=y',
+            cfgutil.adjust_cfg_line(
+                '# CONFIG_FRED is not set', {'FRED':'FRED'})[0])
+
+        # enable a CONFIG that doesn't exist
+        self.assertEqual(
+            ['CONFIG_FRED=y'],
+            cfgutil.adjust_cfg_lines([], {'FRED':'FRED'}))
+
+        # disable a CONFIG that doesn't exist
+        self.assertEqual(
+            ['# CONFIG_FRED is not set'],
+            cfgutil.adjust_cfg_lines([], {'FRED':'~FRED'}))
+
+        # disable a value CONFIG
+        self.assertEqual(
+            '# CONFIG_FRED is not set',
+            cfgutil.adjust_cfg_line('CONFIG_FRED="fred"' , {'FRED':'~FRED'})[0])
+
+        # setting a value CONFIG
+        self.assertEqual(
+            'CONFIG_FRED="fred"',
+            cfgutil.adjust_cfg_line('# CONFIG_FRED is not set' ,
+                                    {'FRED':'FRED="fred"'})[0])
+
+        # changing a value CONFIG
+        self.assertEqual(
+            'CONFIG_FRED="fred"',
+            cfgutil.adjust_cfg_line('CONFIG_FRED="ernie"' ,
+                                    {'FRED':'FRED="fred"'})[0])
+
+        # setting a value for a CONFIG that doesn't exist
+        self.assertEqual(
+            ['CONFIG_FRED="fred"'],
+            cfgutil.adjust_cfg_lines([], {'FRED':'FRED="fred"'}))
+
+    def test_convert_adjust_cfg_list(self):
+        """Check conversion of the list of changes into a dict"""
+        self.assertEqual({}, cfgutil.convert_list_to_dict(None))
+
+        expect = {
+            'FRED':'FRED',
+            'MARY':'~MARY',
+            'JOHN':'JOHN=0x123',
+            'ALICE':'ALICE="alice"',
+            'AMY':'AMY',
+            'ABE':'~ABE',
+            'MARK':'MARK=0x456',
+            'ANNA':'ANNA="anna"',
+            }
+        actual = cfgutil.convert_list_to_dict(
+            ['FRED', '~MARY', 'JOHN=0x123', 'ALICE="alice"',
+             'CONFIG_AMY', '~CONFIG_ABE', 'CONFIG_MARK=0x456',
+             'CONFIG_ANNA="anna"'])
+        self.assertEqual(expect, actual)
+
+    def test_check_cfg_file(self):
+        """Test check_cfg_file detects conflicts as expected"""
+        # Check failure to disable CONFIG
+        result = cfgutil.check_cfg_lines(['CONFIG_FRED=1'], {'FRED':'~FRED'})
+        self.assertEqual([['~FRED', 'CONFIG_FRED=1']], result)
+
+        result = cfgutil.check_cfg_lines(
+            ['CONFIG_FRED=1', 'CONFIG_MARY="mary"'], {'FRED':'~FRED'})
+        self.assertEqual([['~FRED', 'CONFIG_FRED=1']], result)
+
+        result = cfgutil.check_cfg_lines(
+            ['CONFIG_FRED=1', 'CONFIG_MARY="mary"'], {'MARY':'~MARY'})
+        self.assertEqual([['~MARY', 'CONFIG_MARY="mary"']], result)
+
+        # Check failure to enable CONFIG
+        result = cfgutil.check_cfg_lines(
+            ['# CONFIG_FRED is not set'], {'FRED':'FRED'})
+        self.assertEqual([['FRED', '# CONFIG_FRED is not set']], result)
+
+        # Check failure to set CONFIG value
+        result = cfgutil.check_cfg_lines(
+            ['# CONFIG_FRED is not set', 'CONFIG_MARY="not"'],
+            {'MARY':'MARY="mary"', 'FRED':'FRED'})
+        self.assertEqual([
+            ['FRED', '# CONFIG_FRED is not set'],
+            ['MARY="mary"', 'CONFIG_MARY="not"']], result)
+
+        # Check failure to add CONFIG value
+        result = cfgutil.check_cfg_lines([], {'MARY':'MARY="mary"'})
+        self.assertEqual([
+            ['MARY="mary"', 'Missing expected line: CONFIG_MARY="mary"']], result)
+
+
 if __name__ == "__main__":
     unittest.main()