pmb: flasher: frontend: don't fail if kernel config cannot be found (MR 2184)

When using a kernel from Alpine the kernel configuration cannot be
found in pmaports. We cannot check the kernel config for missing
options in that case, but that's no reason to break the flasher
entirely.

pmb/flasher/frontend.py

@@ -20,7 +20,7 @@ def kernel(args):
         pmb.chroot.initfs.build(args, flavor, "rootfs_" + args.device)
 
     # Check kernel config
-    pmb.parse.kconfig.check(args, flavor)
+    pmb.parse.kconfig.check(args, flavor, must_exist=False)
 
     # Generate the paths and run the flasher
     if args.action_flasher == "boot":

pmb/parse/kconfig.py

@@ -167,11 +167,13 @@ def check(args, pkgname,
           force_zram_check=False,
           force_netboot_check=False,
           force_uefi_check=False,
-          details=False):
+          details=False,
+          must_exist=True):
     """
     Check for necessary kernel config options in a package.
 
     :returns: True when the check was successful, False otherwise
+              None if the aport cannot be found (only if must_exist=False)
     """
     # Pkgname: allow omitting "linux-" prefix
     if pkgname.startswith("linux-"):
@@ -181,7 +183,9 @@ def check(args, pkgname,
 
     # Read all kernel configs in the aport
     ret = True
-    aport = pmb.helpers.pmaports.find(args, "linux-" + flavor)
+    aport = pmb.helpers.pmaports.find(args, "linux-" + flavor, must_exist=must_exist)
+    if aport is None:
+        return None
     apkbuild = pmb.parse.apkbuild(f"{aport}/APKBUILD")
     pkgver = apkbuild["pkgver"]
     check_anbox = force_anbox_check or (

test/test_kconfig_check.py

@@ -21,6 +21,10 @@ def args(tmpdir, request):
 
 
 def test_kconfig_check(args):
+    # non-existing package
+    assert pmb.parse.kconfig.check(args, "non-existing-kernel-package",
+                                   must_exist=False) is None
+
     # basic checks, from easiers to hard-ish
     dir = f"{pmb_test.const.testdata}/kconfig_check/"
     assert not pmb.parse.kconfig.check_file(dir +