Variable key replaces original warnings

[Olof Johansson <olof.johansson@axis.com>]

Hi all,

We've started to see issues on master like

   WARNING:
     Variable key          USERADD_PARAM_${PN}             (; --system --home / --no-create-home --comment 'Storage manager daemon' --gid storage storage)
     replaces original key USERADD_PARAM_recording-indexer (--system --home / --no-create-home --comment 'apache httpd' --gid www www).

(my alignment...)

The warning happens when doing

 WWWUSER_PACKAGE ?= "${PN}"
 USERADD_PARAM_${WWWUSER_PACKAGE} := "--system --home / --no-create-home --gid www www"

 USERADD_PARAM_${PN}_append = "; --system --home / --no-create-home --gid username username"

(in reality, the first two lines are inherited from a class, and the third in
the recipe itself.)

With bitbake -e I see what looks like the expected value, with both users being
created. If I change USERADD_PARAM_${WWWUSER_PACKAGE} (second line) to
USERADD_PARAM_${PN} no warning is printed, so this only seems to be a problem
in cases where multiple unique non-expanded vars expand to the same expanded
var.

I made a unit test that should demonstrate the problem (I think), and it fails
because of the warnings:

diff --git a/bitbake/lib/bb/tests/data.py b/bitbake/lib/bb/tests/data.py
index e9aab57..e7716cc 100644
--- a/bitbake/lib/bb/tests/data.py
+++ b/bitbake/lib/bb/tests/data.py
@@ -386,6 +386,15 @@ class TestKeyExpansion(unittest.TestCase):
             self.assertTrue(logContains("Variable key VAL_${FOO} (A) replaces original key VAL_foo (B)", logs))
         self.assertEqual(self.d.getVar("VAL_foo", True), "A")
 
+    def test_append(self):
+        self.d.setVar("TEST_${BAR}", "Bar")
+        self.d.setVar("TEST_${FOO}_append", "Foo")
+        with LogRecord() as logs:
+            bb.data.expandKeys(self.d)
+            self.assertFalse(logContains("Variable key TEST_${FOO} (Foo) replaces original key TEST_foo (Bar)", logs))
+        self.assertEqual(self.d.getVar("TEST_${FOO}", True), "BarFoo")


If you have any ideas on what this issue can be or how to fix it, please
let me know :)

-- 
olof johansson