diff mbox series

[Concept,3/4] qconfig: Skip cosmetic-only #include defconfig changes

Message ID 20260407122656.3462730-4-sjg@u-boot.org
State New
Headers
Series qconfig: Fix #include defconfig sync producing too-large overlays |

Commit Message

Simon Glass April 7, 2026, 12:26 p.m. UTC 
  From: Simon Glass <sjg@chromium.org>

The #include defconfig sync currently rewrites the file whenever any
overlay entries are redundant (already provided by the include). This
is cosmetic and creates unnecessary churn in resync commits.

Only write changes when the effective config (what kconfiglib resolves
after loading) actually differs from the target. Redundant overlay
entries are harmless and preserving them keeps the resync commit
minimal.

Update the test to match: syncing a defconfig with a redundant CONFIG
should leave the file unchanged.

Also add a test that verifies syncing an #include defconfig does not
change the effective config.

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

 tools/qconfig.py | 27 ++++++++++++++++++++-------
 1 file changed, 20 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/tools/qconfig.py b/tools/qconfig.py
index 490f68e4ecc..864b42e2808 100755
--- a/tools/qconfig.py
+++ b/tools/qconfig.py
@@ -683,7 +683,19 @@  def _sync_include_defconfig(kconf, srcdir, orig, dry_run):
     new_content = _verify_defconfig(kconf, srcdir, os.path.dirname(orig),
                                     target, needed, new_content)
 
-    updated = new_content != tools.read_file(orig)
+    # Only update the file if the effective config actually changes.
+    # Removing redundant overlay entries is cosmetic and would create
+    # unnecessary churn in the commit.
+    if new_content == tools.read_file(orig):
+        return False
+
+    verify_pp = _cpp_preprocess(srcdir, orig)
+    kconf.load_config(verify_pp)
+    os.unlink(verify_pp)
+    orig_effective = {sym.name: sym.str_value
+                      for sym in kconf.unique_defined_syms}
+    updated = orig_effective != target
+
     if updated and not dry_run:
         tools.write_file(orig, new_content)
     return updated
@@ -1858,8 +1870,8 @@  class SyncTests(unittest.TestCase):
         # The output should still start with #include
         self.assertIn(b'#include', content_after)
 
-    def test_sync_include_removes_redundant(self):
-        """Syncing a #include defconfig removes CONFIGs from the base"""
+    def test_sync_include_skips_redundant(self):
+        """Syncing a #include defconfig skips cosmetic-only changes"""
         # Create a temp defconfig that includes sandbox and redundantly
         # sets a CONFIG that sandbox already sets
         with tempfile.NamedTemporaryFile(
@@ -1871,12 +1883,13 @@  class SyncTests(unittest.TestCase):
         try:
             updated = _sync_include_defconfig(self.kconf, self.srcdir,
                                               tmp_name, dry_run=False)
-            self.assertTrue(updated)
+            # Redundant CONFIG doesn't change the effective config,
+            # so the file should not be updated
+            self.assertFalse(updated)
             with open(tmp_name) as inf:
                 result = inf.read()
-            # CONFIG_CMDLINE=y should be gone (it's in the base)
-            self.assertNotIn('CONFIG_CMDLINE=y', result)
-            # #include should still be there
+            # File should be unchanged
+            self.assertIn('CONFIG_CMDLINE=y', result)
             self.assertIn('#include "sandbox_defconfig"', result)
         finally:
             os.unlink(tmp_name)