use std::path::PathBuf;
use crate::{
builtins::global_builtins,
errors::{Error, ErrorKind, EvalResult},
nix_search_path::NixSearchPath,
observer::{DisassemblingObserver, NoOpObserver, TracingObserver},
pretty_ast::pretty_print_expr,
value::Value,
SourceCode,
};
/// Runtime options for the Tvix interpreter
#[derive(Debug, Clone, Default)]
#[cfg_attr(feature = "repl", derive(clap::Parser))]
pub struct Options {
/// Dump the raw AST to stdout before interpreting
#[cfg_attr(feature = "repl", clap(long, env = "TVIX_DISPLAY_AST"))]
display_ast: bool,
/// Dump the bytecode to stdout before evaluating
#[cfg_attr(feature = "repl", clap(long, env = "TVIX_DUMP_BYTECODE"))]
dump_bytecode: bool,
/// Trace the runtime of the VM
#[cfg_attr(feature = "repl", clap(long, env = "TVIX_TRACE_RUNTIME"))]
trace_runtime: bool,
/// Print warnings
#[cfg_attr(
feature = "repl",
clap(long, env = "TVIX_WARNINGS", default_value = "true")
)]
warnings: bool,
/// A colon-separated list of directories to use to resolve `<...>`-style paths
#[cfg_attr(feature = "repl", clap(long, short = 'I', env = "NIX_PATH"))]
nix_search_path: Option<NixSearchPath>,
}
impl Options {
#[cfg(test)]
pub(crate) fn test_options() -> Options {
Options {
warnings: false,
..Options::default()
}
}
}
pub fn interpret(code: &str, location: Option<PathBuf>, options: Options) -> EvalResult<Value> {
let source = SourceCode::new();
let file = source.add_file(
location
.as_ref()
.map(|p| p.to_string_lossy().to_string())
.unwrap_or_else(|| "[tvix-repl]".into()),
code.into(),
);
let parsed = rnix::ast::Root::parse(code);
let errors = parsed.errors();
if !errors.is_empty() {
let err = Error {
kind: ErrorKind::ParseErrors(errors.to_vec()),
span: file.span,
};
err.fancy_format_stderr(&source);
return Err(err);
}
// If we've reached this point, there are no errors.
let root_expr = parsed
.tree()
.expr()
.expect("expression should exist if no errors occured");
if options.display_ast {
println!("{}", pretty_print_expr(&root_expr));
}
let builtins = crate::compiler::prepare_globals(Box::new(global_builtins(source.clone())));
let result = if options.dump_bytecode {
crate::compiler::compile(
&root_expr,
location,
file.clone(),
builtins,
&mut DisassemblingObserver::new(source.clone(), std::io::stderr()),
)
} else {
crate::compiler::compile(
&root_expr,
location,
file.clone(),
builtins,
&mut NoOpObserver::default(),
)
}?;
if options.warnings {
for warning in result.warnings {
warning.fancy_format_stderr(&source);
}
}
for error in &result.errors {
error.fancy_format_stderr(&source);
}
if let Some(err) = result.errors.last() {
return Err(err.clone());
}
let result = if options.trace_runtime {
crate::vm::run_lambda(
options.nix_search_path.unwrap_or_default(),
&mut TracingObserver::new(std::io::stderr()),
result.lambda,
)
} else {
crate::vm::run_lambda(
options.nix_search_path.unwrap_or_default(),
&mut NoOpObserver::default(),
result.lambda,
)
};
if let Err(err) = &result {
err.fancy_format_stderr(&source);
}
result.map(|r| {
if options.warnings {
for warning in r.warnings {
warning.fancy_format_stderr(&source);
}
}
r.value
})
}