sjtakada / yang-rs

yang-rs

Rust YANG parser. Supporting RFC7950.

Usage

Parse and dump a YANG file.

cargo run YANG-FILE

Code example to parse YANG string and get parsed Rust object.

use yang_rs::parser::Parser;
use yang_rs::config::Config;
use yang_rs::core::YangStmt;

let mut f = File::open(filename)?;
let mut s = String::new();

f.read_to_string(&mut s)?;

let yang = Parser::parse_yang_from_string(s, config)?;
match yang {
    YangStmt::ModuleStmt(module) => {
        println!("arg {:?}", module.arg());
        println!("arg {:?}", module.module_header().yang_version());
    }
    _ => {}
}

yang-rs's Issues

Parser: double-quoted multi-line string after multi-line block comment

Given the following input for the parser:

/*this is a multi
line comment */ "and this is a quoted multi
                              line string"

When calling parser.get_token():

• Expected result: Token::QuotedString("and this is a quoted multi\nline string")
• Actual result: Token::QuotedString("and this is a quoted multi\n line string")

It has two additional spaces.

Special characters not processed in double quoted string

rfc-6.1.3:

Within a double-quoted string (enclosed within " "), a backslash
character introduces a representation of a special character, which
depends on the character that immediately follows the backslash:

\n      newline
\t      a tab character
\"      a double quote
\\      a single backslash

The backslash MUST NOT be followed by any other character.

Expected
the following double quoted string: a\nb\nc should be translated to:

a
b
c

Actual
The contents of the token is: a\nb\nc

Parser: the parser defines Token::Identifier, whereas an identifier is not a token

RFC-7950 defines tokens here:
https://www.rfc-editor.org/rfc/rfc7950.html#section-6.1.2

And identifiers are defined here:
https://www.rfc-editor.org/rfc/rfc7950.html#section-6.2

The parser defines a token Token::Identifier that is not mentioned in the RFC as a token, only in the ABNF grammar.

This misconception does not lead to any errors, but confusing for the consumer of the Parser. For example, this way, the Token::Identifier may contain a prefix.

The following input:

"my extension" "my argument";

should throw an error, but not on tokenising (lexer) level, but on parser level.