lex-core 0.8.2

Parser library for the lex format
Documentation 
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//! Test factories for creating locations and spanned tokens succinctly.
//!
//! The lexer and parser now require every token to carry a byte-span. These helpers
//! keep tests concise while enforcing that requirement.

use std::ops::Range;

use super::core::Token;

/// Canonical alias for spanned tokens used across tests
pub type Tokens = Vec<(Token, Range<usize>)>;

/// Make a byte range location
pub fn make_loc(start: usize, end: usize) -> Range<usize> {
    start..end
}

/// Make a single spanned token
pub fn mk_token(token: Token, start: usize, end: usize) -> (Token, Range<usize>) {
    (token, make_loc(start, end))
}

/// Make a vector of spanned tokens from a list of (Token, start, end)
pub fn mk_tokens(specs: &[(Token, usize, usize)]) -> Tokens {
    specs
        .iter()
        .cloned()
        .map(|(t, s, e)| mk_token(t, s, e))
        .collect()
}

/// Create tokens with zero-length spans for convenience in tests that only
/// care about token order.
pub fn mk_tokens_with_dummy_span(tokens: Vec<Token>) -> Tokens {
    tokens
        .into_iter()
        .map(|token| mk_token(token, 0, 0))
        .collect()
}