qemu/tests/qapi-schema
Markus Armbruster c7a3f25200 qapi.py: Restructure lexer and parser
The parser has a rather unorthodox structure:

    Until EOF:

        Read a section:

            Generator function get_expr() yields one section after the
            other, as a string.  An unindented, non-empty line that
            isn't a comment starts a new section.

        Lexing:

            Split section into a list of tokens (strings), with help
            of generator function tokenize().

        Parsing:

            Parse the first expression from the list of tokens, with
            parse(), throw away any remaining tokens.

            In parse_schema(): record value of an enum, union or
            struct key (if any) in the appropriate global table,
            append expression to the list of expressions.

    Return list of expressions.

Known issues:

(1) Indentation is significant, unlike in real JSON.

(2) Neither lexer nor parser have any idea of source positions.  Error
    reporting is hard, let's go shopping.

(3) The one error we bother to detect, we "report" via raise.

(4) The lexer silently ignores invalid characters.

(5) If everything in a section gets ignored, the parser crashes.

(6) The lexer treats a string containing a structural character exactly
    like the structural character.

(7) Tokens trailing the first expression in a section are silently
    ignored.

(8) The parser accepts any token in place of a colon.

(9) The parser treats comma as optional.

(10) parse() crashes on unexpected EOF.

(11) parse_schema() crashes when a section's expression isn't a JSON
    object.

Replace this piece of original art by a thoroughly unoriginal design.
Takes care of (1), (2), (5), (6) and (7), and lays the groundwork for
addressing the others.  Generated source files remain unchanged.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1374939721-7876-4-git-send-email-armbru@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-07-29 10:37:10 -05:00
..
comments.err
comments.exit
comments.json
comments.out
empty.err
empty.exit
empty.json
empty.out
funny-char.err
funny-char.exit
funny-char.json
funny-char.out
indented-expr.err
indented-expr.exit
indented-expr.json
indented-expr.out qapi.py: Restructure lexer and parser 2013-07-29 10:37:10 -05:00
missing-colon.err
missing-colon.exit
missing-colon.json
missing-colon.out qapi.py: Restructure lexer and parser 2013-07-29 10:37:10 -05:00
missing-comma-list.err
missing-comma-list.exit
missing-comma-list.json
missing-comma-list.out
missing-comma-object.err
missing-comma-object.exit
missing-comma-object.json
missing-comma-object.out
non-objects.err
non-objects.exit
non-objects.json
non-objects.out
qapi-schema-test.err
qapi-schema-test.exit
qapi-schema-test.json
qapi-schema-test.out
quoted-structural-chars.err qapi.py: Restructure lexer and parser 2013-07-29 10:37:10 -05:00
quoted-structural-chars.exit qapi.py: Restructure lexer and parser 2013-07-29 10:37:10 -05:00
quoted-structural-chars.json
quoted-structural-chars.out qapi.py: Restructure lexer and parser 2013-07-29 10:37:10 -05:00
test-qapi.py
trailing-comma-list.err
trailing-comma-list.exit
trailing-comma-list.json
trailing-comma-list.out
trailing-comma-object.err
trailing-comma-object.exit
trailing-comma-object.json
trailing-comma-object.out
unclosed-list.err
unclosed-list.exit
unclosed-list.json
unclosed-list.out
unclosed-object.err
unclosed-object.exit
unclosed-object.json
unclosed-object.out
unclosed-string.err
unclosed-string.exit
unclosed-string.json
unclosed-string.out