lib/bbconfigbuild/configfragments: disable the previous builtin fragment when enabling a new one

There was a flaw in the logic that allowed multiple builtin fragments with
the same prefix to be enabled at the same time. The correct behaviour
is that only one of them should be enabled, and when enabling it
all previously enabled fragments should be removed.

The issues that this caused are further explained in
https://bugzilla.yoctoproject.org/show_bug.cgi?id=15987

[YOCTO #15987]

(From OE-Core rev: 4cc78af26d8c3154d4f2b3b37d8e4dc65485eb66)

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

1 files changed, 9 insertions, 6 deletions

diff --git a/meta/lib/oeqa/selftest/cases/bblayers.py b/meta/lib/oeqa/selftest/cases/bblayers.py
index d82c5aaf37..7eb176aa04 100644
--- a/meta/lib/oeqa/selftest/cases/bblayers.py
+++ b/meta/lib/oeqa/selftest/cases/bblayers.py
@@ -281,11 +281,11 @@ class BitbakeConfigBuild(OESelftestTestCase):
         2. Verify that SELFTEST_BUILTIN_FRAGMENT_VARIABLE is set after setting
            the fragment.
         3. Verify that SELFTEST_BUILTIN_FRAGMENT_VARIABLE is set after setting
-           the fragment with another value that overrides the first one.
-        4. Verify that SELFTEST_BUILTIN_FRAGMENT_VARIABLE is set to the previous
-           value after removing the second assignment (from step 3).
+           the fragment with another value that replaces the first one.
+        4. Repeat steps 2 and 3 to verify that going back and forth between values
+           works.
         5. Verify that SELFTEST_BUILTIN_FRAGMENT_VARIABLE is not set after
-           removing the original assignment.
+           removing the final assignment.
         """
         self.assertEqual(get_bb_var('SELFTEST_BUILTIN_FRAGMENT_VARIABLE'), None)
 
@@ -295,10 +295,13 @@ class BitbakeConfigBuild(OESelftestTestCase):
         runCmd('bitbake-config-build enable-fragment selftest-fragment/someothervalue')
         self.assertEqual(get_bb_var('SELFTEST_BUILTIN_FRAGMENT_VARIABLE'), 'someothervalue')
 
-        runCmd('bitbake-config-build disable-fragment selftest-fragment/someothervalue')
+        runCmd('bitbake-config-build enable-fragment selftest-fragment/somevalue')
         self.assertEqual(get_bb_var('SELFTEST_BUILTIN_FRAGMENT_VARIABLE'), 'somevalue')
 
-        runCmd('bitbake-config-build disable-fragment selftest-fragment/somevalue')
+        runCmd('bitbake-config-build enable-fragment selftest-fragment/someothervalue')
+        self.assertEqual(get_bb_var('SELFTEST_BUILTIN_FRAGMENT_VARIABLE'), 'someothervalue')
+
+        runCmd('bitbake-config-build disable-fragment selftest-fragment/someothervalue')
         self.assertEqual(get_bb_var('SELFTEST_BUILTIN_FRAGMENT_VARIABLE'), None)
 
     def test_show_fragment(self):