veripb-parser 0.1.2

//! Definitions of parsing errors.

use std::ops::Range;

use thiserror::Error;

/// An error from the VeriPB parsing library.
#[derive(Debug, Error)]
pub enum ParserError {
    /// Error related to reading the file.
    #[error("Failed to open file!")]
    IOError(
        #[from]
        #[source]
        std::io::Error,
    ),

    #[error("Failed to open file! File '{0}' might not exist?")]
    FileError(String),

    #[error("Unexpected token starting at position {}! Expected: {expected}!", .span.start + 1)]
    TokenError {
        span: Range<usize>,
        expected: String,
    },

    #[error("Unexpected token starting at {filename}:{}:{}! Expected {expected}!", .line+1, .span.start + 1, )]
    TokenErrorFile {
        span: Range<usize>,
        expected: String,
        line: usize,
        filename: String,
    },

    #[error{"Constraint ID parsing error!"}]
    ParseIntError(
        #[from]
        #[source]
        std::num::ParseIntError,
    ),

    #[error("The file did not contain a header, which is required for this input file format!")]
    NoHeader,
}

impl ParserError {
    pub fn token_error(span: Range<usize>, expected: &str) -> Self {
        Self::TokenError {
            span,
            expected: expected.to_string(),
        }
    }

    pub fn token_error_with_file(
        span: Range<usize>,
        expected: &str,
        filename: String,
        line: usize,
    ) -> Self {
        Self::TokenErrorFile {
            span,
            expected: expected.to_string(),
            line,
            filename,
        }
    }

    pub fn add_file_and_line(self, filename: String, line: usize) -> Option<Self> {
        match self {
            Self::TokenError { span, expected } => Some(Self::TokenErrorFile {
                span,
                expected,
                line,
                filename,
            }),
            _ => None,
        }
    }
}