leo/parser/examples/parser.rs
2022-01-21 12:32:09 -08:00

71 lines
2.8 KiB
Rust

// Copyright (C) 2019-2022 Aleo Systems Inc.
// This file is part of the Leo library.
// The Leo library is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// The Leo library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with the Leo library. If not, see <https://www.gnu.org/licenses/>.
use leo_ast::Ast;
use leo_errors::{emitter::Handler, Result};
use leo_span::symbol::create_session_if_not_set_then;
use std::{env, fs, path::Path};
fn to_leo_tree(filepath: &Path) -> Result<String> {
// Loads the Leo code as a string from the given file path.
let program_filepath = filepath.to_path_buf();
let program_string = fs::read_to_string(&program_filepath).expect("failed to open input file");
// Parses the Leo file constructing an ast which is then serialized.
create_session_if_not_set_then(|_| {
let handler = Handler::default();
let ast = leo_parser::parse_ast(&handler, filepath.to_str().unwrap(), &program_string)?;
Ok(Ast::to_json_string(&ast).expect("serialization failed"))
})
}
fn main() -> Result<()> {
// Parse the command-line arguments as strings.
let cli_arguments = env::args().collect::<Vec<String>>();
// Check that the correct number of command-line arguments were passed in.
if cli_arguments.len() < 2 || cli_arguments.len() > 3 {
eprintln!("Warning - an invalid number of command-line arguments were provided.");
println!(
"\nCommand-line usage:\n\n\tleo_ast {{PATH/TO/INPUT_FILENAME}}.leo {{PATH/TO/OUTPUT_DIRECTORY (optional)}}\n"
);
return Ok(()); // Exit innocently
}
// Construct the input filepath.
let input_filepath = Path::new(&cli_arguments[1]);
// Construct the serialized syntax tree.
let serialized_leo_tree = to_leo_tree(input_filepath)?;
println!("{}", serialized_leo_tree);
// Determine the output directory.
let output_directory = match cli_arguments.len() == 3 {
true => format!(
"{}/{}.json",
cli_arguments[2],
input_filepath.file_stem().unwrap().to_str().unwrap()
),
false => format!("./{}.json", input_filepath.file_stem().unwrap().to_str().unwrap()),
};
// Write the serialized syntax tree to the output directory.
fs::write(Path::new(&output_directory), serialized_leo_tree).expect("failed to write output");
Ok(())
}