meli/text_processing/build.rs
Manos Pitsidianakis 321be8555f
Cleanup startup error exit paths
Make startup methods return Results so that the main binary can exit
cleanly instead of using std::process::exit from arbitrary positions,
which exits the process immediately and doesn't run destructors.
2019-11-16 00:33:22 +02:00

74 lines
2.6 KiB
Rust

const LINE_BREAK_TABLE_URL: &str = "http://www.unicode.org/Public/UCD/latest/ucd/LineBreak.txt";
use std::fs::File;
use std::io::prelude::*;
use std::io::BufReader;
use std::path::{Path, PathBuf};
use std::process::Command;
include!("src/types.rs");
fn main() -> Result<(), std::io::Error> {
let mod_path = Path::new("src/tables.rs");
if mod_path.exists() {
eprintln!(
"{} already exists, delete it if you want to replace it.",
mod_path.display()
);
std::process::exit(0);
}
let mut tmpdir_path = PathBuf::from(
std::str::from_utf8(&Command::new("mktemp").arg("-d").output()?.stdout)
.unwrap()
.trim(),
);
tmpdir_path.push("LineBreak.txt");
Command::new("curl")
.args(&["-o", tmpdir_path.to_str().unwrap(), LINE_BREAK_TABLE_URL])
.output()?;
let file = File::open(&tmpdir_path)?;
let buf_reader = BufReader::new(file);
let mut line_break_table: Vec<(u32, u32, LineBreakClass)> = Vec::with_capacity(3800);
for line in buf_reader.lines() {
let line = line.unwrap();
if line.starts_with('#') || line.starts_with(' ') || line.is_empty() {
continue;
}
let tokens: &str = line.split_whitespace().next().unwrap();
let semicolon_idx: usize = tokens.chars().position(|c| c == ';').unwrap();
/* LineBreak.txt list is ascii encoded so we can assume each char takes one byte: */
let chars_str: &str = &tokens[..semicolon_idx];
let mut codepoint_iter = chars_str.split("..");
let first_codepoint: u32 =
u32::from_str_radix(std::dbg!(codepoint_iter.next().unwrap()), 16).unwrap();
let sec_codepoint: u32 = codepoint_iter
.next()
.map(|v| u32::from_str_radix(std::dbg!(v), 16).unwrap())
.unwrap_or(first_codepoint);
let class = &tokens[semicolon_idx + 1..semicolon_idx + 1 + 2];
line_break_table.push((first_codepoint, sec_codepoint, LineBreakClass::from(class)));
}
let mut file = File::create(&mod_path)?;
file.write_all(b"use crate::types::LineBreakClass::*;\n")
.unwrap();
file.write_all(b"use crate::types::LineBreakClass;\n\n")
.unwrap();
file.write_all(b"const line_break_rules: &'static [(u32, u32, LineBreakClass)] = &[\n")
.unwrap();
for l in &line_break_table {
file.write_all(format!(" (0x{:X}, 0x{:X}, {:?}),\n", l.0, l.1, l.2).as_bytes())
.unwrap();
}
file.write_all(b"];").unwrap();
std::fs::remove_file(&tmpdir_path).unwrap();
tmpdir_path.pop();
std::fs::remove_dir(&tmpdir_path).unwrap();
Ok(())
}