## has one non-nul byte in header padding

## VALID_HEADER includes a LENGTH Header and LENGTH Body
VALID_HEADER method_call

HEADER_FIELD INTERFACE
TYPE STRING
STRING 'org.freedesktop.Foo'
HEADER_FIELD MEMBER
TYPE STRING
STRING 'Bar'
HEADER_FIELD PATH
TYPE OBJECT_PATH
OBJECT_PATH '/foo'

HEADER_FIELD UNKNOWN
TYPE STRING
STRING 'a'
ALIGN 8
## kill a padding byte and replace it
CHOP 1
BYTE 'q'
END_LENGTH Header
START_LENGTH Body
END_LENGTH Body