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use crate::debug_level;
use crate::source::CustomDecoder;
use crate::token_rewriter::TokenRewriter;
/// Configuration of the parser
#[derive(Debug)]
pub struct ParserOptions {
/// Name of the buffer. Used in all diagnostic messages
pub buffer_name: String,
/// Controls which debug information is printed during parsing
///
/// Can be:
///
/// + lib_ruby_parser::debug_level::None
/// + lib_ruby_parser::debug_level::Parser
/// + lib_ruby_parser::debug_level::Lexer
/// + lib_ruby_parser::debug_level::Buffer
/// + or a combination of them (like `Lexer | Buffer`, these value is just a bitmask)
pub debug: debug_level::Type,
/// Custom decoder that can be used if the source is encoded
/// in unknown encoding. Only UTF-8 and ASCII-8BIT/BINARY are
/// supported out of the box.
///
/// # Example
/// ```rust
/// use lib_ruby_parser::source::{CustomDecoder, CustomDecoderResult, InputError};
/// use lib_ruby_parser::{debug_level, Parser, ParserOptions, ParserResult};
///
/// fn decode(encoding: String, input: Vec<u8>) -> CustomDecoderResult {
/// if "US-ASCII" == encoding.to_uppercase() {
/// // reencode and return Ok(result)
/// return CustomDecoderResult::Ok(b"# encoding: us-ascii\ndecoded".to_vec().into());
/// }
/// CustomDecoderResult::Err(InputError::DecodingError(
/// "only us-ascii is supported".into(),
/// ))
/// }
///
/// let decoder = CustomDecoder::new(Box::new(decode));
/// let options = ParserOptions {
/// decoder,
/// debug: debug_level::PARSER,
/// ..Default::default()
/// };
/// let parser = Parser::new(b"# encoding: us-ascii\n3 + 3".to_vec(), options);
/// let ParserResult { ast, input, .. } = parser.do_parse();
///
/// assert_eq!(
/// ast.unwrap().expression().source(&input).unwrap(),
/// "decoded".to_string()
/// )
/// ```
pub decoder: CustomDecoder,
/// Optional token rewriter, see TokenRewriter API
///
/// # Example
/// ```
/// use lib_ruby_parser::{
/// nodes::*,
/// token_rewriter::*,
/// Bytes, BytesTrait, Node, Parser, ParserOptions, ParserResult, Token, TokenTrait,
/// };
/// fn rewrite_foo_to_bar(mut token: Box<Token>, input: &[u8]) -> TokenRewriterResult {
/// // simply rewrite all tokens "foo" to "bar"
/// if token.to_string_lossy() == "foo" {
/// token.set_token_value(Bytes::new(b"bar".to_vec()));
/// }
///
/// // return token + keep it + keep lexer's state
/// TokenRewriterResult {
/// rewritten_token: token,
/// token_action: RewriteAction::Keep,
/// lex_state_action: LexStateAction::Keep,
/// }
/// }
/// let token_rewriter = TokenRewriter::new(Box::new(rewrite_foo_to_bar));
/// let options = ParserOptions {
/// token_rewriter,
/// ..Default::default()
/// };
/// let ParserResult { ast, .. } = Parser::new(b"foo = 1".to_vec(), options).do_parse();
///
/// let ast = ast.unwrap();
///
/// let lvar_name = match &*ast {
/// Node::Lvasgn(Lvasgn { name, .. }) => name,
/// other => panic!("expected lvasgn node, got {:?}", other),
/// };
/// assert_eq!(*lvar_name, String::from("bar"));
/// ```
pub token_rewriter: TokenRewriter,
/// When set to true Parser records tokens.
/// When set to false `ParserResult.tokens` is guaranteed to be empty.
/// If you don't need tokens better set it to false to speed up parsing.
pub record_tokens: bool,
}
const DEFAULT_BUFFER_NAME: &str = "(eval)";
impl Default for ParserOptions {
fn default() -> Self {
Self {
buffer_name: DEFAULT_BUFFER_NAME.to_string(),
debug: debug_level::NONE,
decoder: CustomDecoder::none(),
token_rewriter: TokenRewriter::none(),
record_tokens: true,
}
}
}