Ok,

PyErr(PyBaseExceptionRef),

ContinueBlock,

ContinueLine,

vm: &VirtualMachine,

source: &str,

scope: Scope,

empty_line_given: bool,

continuing_block: bool,

) -> ShellExecResult {

// compiling expects only UNIX style line endings, and will replace windows line endings

// internally. Since we might need to analyze the source to determine if an error could be

// resolved by future input, we need the location from the error to match the source code that

// was actually compiled.

#[cfg(windows)]

let source = &source.replace("\r\n", "\n");

match vm.compile(source, compiler::Mode::Single, "<stdin>".to_owned()) {

Ok(code) => {

if empty_line_given || !continuing_block {

// We want to execute the full code

match vm.run_code_obj(code, scope) {

Ok(_val) => ShellExecResult::Ok,

Err(err) => ShellExecResult::PyErr(err),

}

} else {

// We can just return an ok result

ShellExecResult::Ok

}

}

Err(CompileError::Parse(ParseError {

error: ParseErrorType::Lexical(LexicalErrorType::Eof),

..

})) => ShellExecResult::ContinueLine,

Err(CompileError::Parse(ParseError {

error:

ParseErrorType::Lexical(LexicalErrorType::FStringError(

InterpolatedStringErrorType::UnterminatedTripleQuotedString,

)),

..

})) => ShellExecResult::ContinueLine,

Err(err) => {

// Check if the error is from an unclosed triple quoted string (which should always

// continue)

if let CompileError::Parse(ParseError {

error: ParseErrorType::Lexical(LexicalErrorType::UnclosedStringError),

raw_location,

..

}) = err

{

let loc = raw_location.start().to_usize();

let mut iter = source.chars();

if let Some(quote) = iter.nth(loc)

&& iter.next() == Some(quote)

&& iter.next() == Some(quote)

{

return ShellExecResult::ContinueLine;

}

};

// bad_error == true if we are handling an error that should be thrown even if we are continuing

// if its an indentation error, set to true if we are continuing and the error is on column 0,

// since indentations errors on columns other than 0 should be ignored.

// if its an unrecognized token for dedent, set to false

let bad_error = match err {

CompileError::Parse(ref p) => {

match &p.error {

ParseErrorType::Lexical(LexicalErrorType::IndentationError) => {

continuing_block

} // && p.location.is_some()

ParseErrorType::OtherError(msg) => {

!msg.starts_with("Expected an indented block")

}

_ => true, // !matches!(p, ParseErrorType::UnrecognizedToken(Tok::Dedent, _))

}

}

_ => true, // It is a bad error for everything else

};

// If we are handling an error on an empty line or an error worthy of throwing

if empty_line_given || bad_error {

ShellExecResult::PyErr(vm.new_syntax_error(&err, Some(source)))

} else {

ShellExecResult::ContinueBlock

}

}

}

let mut repl = Readline::new(helper::ShellHelper::new(vm, scope.globals.clone()));

let mut full_input = String::new();

// Retrieve a `history_path_str` dependent on the OS

let repl_history_path = match dirs::config_dir() {

Some(mut path) => {

path.push("rustpython");

path.push("repl_history.txt");

path

}

None => ".repl_history.txt".into(),

};

if repl.load_history(&repl_history_path).is_err() {

println!("No previous history.");

}

// We might either be waiting to know if a block is complete, or waiting to know if a multiline

// statement is complete. In the former case, we need to ensure that we read one extra new line

// to know that the block is complete. In the latter, we can execute as soon as the statement is

// valid.

let mut continuing_block = false;

let mut continuing_line = false;

loop {

let prompt_name = if continuing_block || continuing_line {

"ps2"

} else {

"ps1"

};

let prompt = vm

.sys_module

.get_attr(prompt_name, vm)

.and_then(|prompt| prompt.str(vm));

let prompt = match prompt {

Ok(ref s) => s.expect_str(),

Err(_) => "",

};

continuing_line = false;

let result = match repl.readline(prompt) {

ReadlineResult::Line(line) => {

#[cfg(debug_assertions)]

debug!("You entered {line:?}");

repl.add_history_entry(line.trim_end()).unwrap();

let empty_line_given = line.is_empty();

if full_input.is_empty() {

full_input = line;

} else {

full_input.push_str(&line);

}

full_input.push('\n');

match shell_exec(

vm,

&full_input,

scope.clone(),

empty_line_given,

continuing_block,

) {

ShellExecResult::Ok => {

if continuing_block {

if empty_line_given {

// We should exit continue mode since the block successfully executed

continuing_block = false;

full_input.clear();

}

} else {

// We aren't in continue mode so proceed normally

full_input.clear();

}

Ok(())

}

// Continue, but don't change the mode

ShellExecResult::ContinueLine => {

continuing_line = true;

Ok(())

}

ShellExecResult::ContinueBlock => {

continuing_block = true;

Ok(())

}

ShellExecResult::PyErr(err) => {

continuing_block = false;

full_input.clear();

Err(err)

}

}

}

ReadlineResult::Interrupt => {

continuing_block = false;

full_input.clear();

let keyboard_interrupt =

vm.new_exception_empty(vm.ctx.exceptions.keyboard_interrupt.to_owned());

Err(keyboard_interrupt)

}

ReadlineResult::Eof => {

break;

}

#[cfg(unix)]

ReadlineResult::OsError(num) => {

let os_error = vm.new_exception_msg(

vm.ctx.exceptions.os_error.to_owned(),

format!("{num:?}").into(),

);

vm.print_exception(os_error);

break;

}

ReadlineResult::Other(err) => {

eprintln!("Readline error: {err:?}");

break;

}

ReadlineResult::Io(err) => {

eprintln!("IO error: {err:?}");

break;

}

};

if let Err(exc) = result {

if exc.fast_isinstance(vm.ctx.exceptions.system_exit) {

repl.save_history(&repl_history_path).unwrap();

return Err(exc);

}

vm.print_exception(exc);

}

}

repl.save_history(&repl_history_path).unwrap();

Ok(())