Files
ruff/src/pycodestyle/rules.rs

638 lines
21 KiB
Rust

use itertools::izip;
use once_cell::sync::Lazy;
use regex::Regex;
use rustc_hash::FxHashMap;
use rustpython_ast::{Arguments, Constant, Excepthandler, Location, Stmt, StmtKind, Unaryop};
use rustpython_parser::ast::{Cmpop, Expr, ExprKind};
use crate::ast::helpers;
use crate::ast::helpers::{
create_expr, except_range, match_leading_content, match_trailing_content, unparse_expr,
};
use crate::ast::types::Range;
use crate::ast::whitespace::leading_space;
use crate::checkers::ast::Checker;
use crate::fix::Fix;
use crate::registry::Diagnostic;
use crate::settings::Settings;
use crate::source_code::{Generator, Locator, Stylist};
use crate::violations;
static URL_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"^https?://\S+$").unwrap());
fn is_overlong(
line: &str,
line_length: usize,
limit: usize,
ignore_overlong_task_comments: bool,
task_tags: &[String],
) -> bool {
if line_length <= limit {
return false;
}
let mut chunks = line.split_whitespace();
let (Some(first), Some(second)) = (chunks.next(), chunks.next()) else {
// Single word / no printable chars - no way to make the line shorter
return false;
};
if first == "#" {
if ignore_overlong_task_comments {
let second = second.trim_end_matches(':');
if task_tags.iter().any(|tag| tag == second) {
return false;
}
}
// Do not enforce the line length for commented lines that end with a URL
// or contain only a single word.
if chunks.last().map_or(true, |c| URL_REGEX.is_match(c)) {
return false;
}
}
true
}
/// E501
pub fn line_too_long(lineno: usize, line: &str, settings: &Settings) -> Option<Diagnostic> {
let line_length = line.chars().count();
let limit = settings.line_length;
if is_overlong(
line,
line_length,
limit,
settings.pycodestyle.ignore_overlong_task_comments,
&settings.task_tags,
) {
Some(Diagnostic::new(
violations::LineTooLong(line_length, limit),
Range::new(
Location::new(lineno + 1, limit),
Location::new(lineno + 1, line_length),
),
))
} else {
None
}
}
/// W505
pub fn doc_line_too_long(lineno: usize, line: &str, settings: &Settings) -> Option<Diagnostic> {
let Some(limit) = settings.pycodestyle.max_doc_length else {
return None;
};
let line_length = line.chars().count();
if is_overlong(
line,
line_length,
limit,
settings.pycodestyle.ignore_overlong_task_comments,
&settings.task_tags,
) {
Some(Diagnostic::new(
violations::DocLineTooLong(line_length, limit),
Range::new(
Location::new(lineno + 1, limit),
Location::new(lineno + 1, line_length),
),
))
} else {
None
}
}
fn compare(left: &Expr, ops: &[Cmpop], comparators: &[Expr], stylist: &Stylist) -> String {
unparse_expr(
&create_expr(ExprKind::Compare {
left: Box::new(left.clone()),
ops: ops.to_vec(),
comparators: comparators.to_vec(),
}),
stylist,
)
}
/// E711, E712
pub fn literal_comparisons(
checker: &mut Checker,
expr: &Expr,
left: &Expr,
ops: &[Cmpop],
comparators: &[Expr],
check_none_comparisons: bool,
check_true_false_comparisons: bool,
) {
// Mapping from (bad operator index) to (replacement operator). As we iterate
// through the list of operators, we apply "dummy" fixes for each error,
// then replace the entire expression at the end with one "real" fix, to
// avoid conflicts.
let mut bad_ops: FxHashMap<usize, Cmpop> = FxHashMap::default();
let mut diagnostics: Vec<Diagnostic> = vec![];
let op = ops.first().unwrap();
// Check `left`.
let mut comparator = left;
let next = &comparators[0];
if check_none_comparisons
&& matches!(
comparator.node,
ExprKind::Constant {
value: Constant::None,
kind: None
}
)
{
if matches!(op, Cmpop::Eq) {
let diagnostic = Diagnostic::new(
violations::NoneComparison(op.into()),
Range::from_located(comparator),
);
if checker.patch(diagnostic.kind.code()) && !helpers::is_constant_non_singleton(next) {
bad_ops.insert(0, Cmpop::Is);
}
diagnostics.push(diagnostic);
}
if matches!(op, Cmpop::NotEq) {
let diagnostic = Diagnostic::new(
violations::NoneComparison(op.into()),
Range::from_located(comparator),
);
if checker.patch(diagnostic.kind.code()) && !helpers::is_constant_non_singleton(next) {
bad_ops.insert(0, Cmpop::IsNot);
}
diagnostics.push(diagnostic);
}
}
if check_true_false_comparisons {
if let ExprKind::Constant {
value: Constant::Bool(value),
kind: None,
} = comparator.node
{
if matches!(op, Cmpop::Eq) {
let diagnostic = Diagnostic::new(
violations::TrueFalseComparison(value, op.into()),
Range::from_located(comparator),
);
if checker.patch(diagnostic.kind.code())
&& !helpers::is_constant_non_singleton(next)
{
bad_ops.insert(0, Cmpop::Is);
}
diagnostics.push(diagnostic);
}
if matches!(op, Cmpop::NotEq) {
let diagnostic = Diagnostic::new(
violations::TrueFalseComparison(value, op.into()),
Range::from_located(comparator),
);
if checker.patch(diagnostic.kind.code())
&& !helpers::is_constant_non_singleton(next)
{
bad_ops.insert(0, Cmpop::IsNot);
}
diagnostics.push(diagnostic);
}
}
}
// Check each comparator in order.
for (idx, (op, next)) in izip!(ops, comparators).enumerate() {
if check_none_comparisons
&& matches!(
next.node,
ExprKind::Constant {
value: Constant::None,
kind: None
}
)
{
if matches!(op, Cmpop::Eq) {
let diagnostic = Diagnostic::new(
violations::NoneComparison(op.into()),
Range::from_located(next),
);
if checker.patch(diagnostic.kind.code())
&& !helpers::is_constant_non_singleton(comparator)
{
bad_ops.insert(idx, Cmpop::Is);
}
diagnostics.push(diagnostic);
}
if matches!(op, Cmpop::NotEq) {
let diagnostic = Diagnostic::new(
violations::NoneComparison(op.into()),
Range::from_located(next),
);
if checker.patch(diagnostic.kind.code())
&& !helpers::is_constant_non_singleton(comparator)
{
bad_ops.insert(idx, Cmpop::IsNot);
}
diagnostics.push(diagnostic);
}
}
if check_true_false_comparisons {
if let ExprKind::Constant {
value: Constant::Bool(value),
kind: None,
} = next.node
{
if matches!(op, Cmpop::Eq) {
let diagnostic = Diagnostic::new(
violations::TrueFalseComparison(value, op.into()),
Range::from_located(next),
);
if checker.patch(diagnostic.kind.code())
&& !helpers::is_constant_non_singleton(comparator)
{
bad_ops.insert(idx, Cmpop::Is);
}
diagnostics.push(diagnostic);
}
if matches!(op, Cmpop::NotEq) {
let diagnostic = Diagnostic::new(
violations::TrueFalseComparison(value, op.into()),
Range::from_located(next),
);
if checker.patch(diagnostic.kind.code())
&& !helpers::is_constant_non_singleton(comparator)
{
bad_ops.insert(idx, Cmpop::IsNot);
}
diagnostics.push(diagnostic);
}
}
}
comparator = next;
}
// TODO(charlie): Respect `noqa` directives. If one of the operators has a
// `noqa`, but another doesn't, both will be removed here.
if !bad_ops.is_empty() {
// Replace the entire comparison expression.
let ops = ops
.iter()
.enumerate()
.map(|(idx, op)| bad_ops.get(&idx).unwrap_or(op))
.cloned()
.collect::<Vec<_>>();
let content = compare(left, &ops, comparators, checker.style);
for diagnostic in &mut diagnostics {
diagnostic.amend(Fix::replacement(
content.to_string(),
expr.location,
expr.end_location.unwrap(),
));
}
}
checker.diagnostics.extend(diagnostics);
}
/// E713, E714
pub fn not_tests(
checker: &mut Checker,
expr: &Expr,
op: &Unaryop,
operand: &Expr,
check_not_in: bool,
check_not_is: bool,
) {
if matches!(op, Unaryop::Not) {
if let ExprKind::Compare {
left,
ops,
comparators,
..
} = &operand.node
{
let should_fix = ops.len() == 1;
for op in ops.iter() {
match op {
Cmpop::In => {
if check_not_in {
let mut diagnostic = Diagnostic::new(
violations::NotInTest,
Range::from_located(operand),
);
if checker.patch(diagnostic.kind.code()) && should_fix {
diagnostic.amend(Fix::replacement(
compare(left, &[Cmpop::NotIn], comparators, checker.style),
expr.location,
expr.end_location.unwrap(),
));
}
checker.diagnostics.push(diagnostic);
}
}
Cmpop::Is => {
if check_not_is {
let mut diagnostic = Diagnostic::new(
violations::NotIsTest,
Range::from_located(operand),
);
if checker.patch(diagnostic.kind.code()) && should_fix {
diagnostic.amend(Fix::replacement(
compare(left, &[Cmpop::IsNot], comparators, checker.style),
expr.location,
expr.end_location.unwrap(),
));
}
checker.diagnostics.push(diagnostic);
}
}
_ => {}
}
}
}
}
}
/// E721
pub fn type_comparison(ops: &[Cmpop], comparators: &[Expr], location: Range) -> Vec<Diagnostic> {
let mut diagnostics: Vec<Diagnostic> = vec![];
for (op, right) in izip!(ops, comparators) {
if !matches!(op, Cmpop::Is | Cmpop::IsNot | Cmpop::Eq | Cmpop::NotEq) {
continue;
}
match &right.node {
ExprKind::Call { func, args, .. } => {
if let ExprKind::Name { id, .. } = &func.node {
// Ex) type(False)
if id == "type" {
if let Some(arg) = args.first() {
// Allow comparison for types which are not obvious.
if !matches!(
arg.node,
ExprKind::Name { .. }
| ExprKind::Constant {
value: Constant::None,
kind: None
}
) {
diagnostics
.push(Diagnostic::new(violations::TypeComparison, location));
}
}
}
}
}
ExprKind::Attribute { value, .. } => {
if let ExprKind::Name { id, .. } = &value.node {
// Ex) types.IntType
if id == "types" {
diagnostics.push(Diagnostic::new(violations::TypeComparison, location));
}
}
}
_ => {}
}
}
diagnostics
}
/// E722
pub fn do_not_use_bare_except(
type_: Option<&Expr>,
body: &[Stmt],
handler: &Excepthandler,
locator: &Locator,
) -> Option<Diagnostic> {
if type_.is_none()
&& !body
.iter()
.any(|stmt| matches!(stmt.node, StmtKind::Raise { exc: None, .. }))
{
Some(Diagnostic::new(
violations::DoNotUseBareExcept,
except_range(handler, locator),
))
} else {
None
}
}
fn function(name: &str, args: &Arguments, body: &Expr, stylist: &Stylist) -> String {
let body = Stmt::new(
Location::default(),
Location::default(),
StmtKind::Return {
value: Some(Box::new(body.clone())),
},
);
let func = Stmt::new(
Location::default(),
Location::default(),
StmtKind::FunctionDef {
name: name.to_string(),
args: Box::new(args.clone()),
body: vec![body],
decorator_list: vec![],
returns: None,
type_comment: None,
},
);
let mut generator: Generator = stylist.into();
generator.unparse_stmt(&func);
generator.generate()
}
/// E731
pub fn do_not_assign_lambda(checker: &mut Checker, target: &Expr, value: &Expr, stmt: &Stmt) {
if let ExprKind::Name { id, .. } = &target.node {
if let ExprKind::Lambda { args, body } = &value.node {
let mut diagnostic = Diagnostic::new(
violations::DoNotAssignLambda(id.to_string()),
Range::from_located(stmt),
);
if checker.patch(diagnostic.kind.code()) {
if !match_leading_content(stmt, checker.locator)
&& !match_trailing_content(stmt, checker.locator)
{
let first_line = checker.locator.slice_source_code_range(&Range::new(
Location::new(stmt.location.row(), 0),
Location::new(stmt.location.row() + 1, 0),
));
let indentation = &leading_space(&first_line);
let mut indented = String::new();
for (idx, line) in function(id, args, body, checker.style).lines().enumerate() {
if idx == 0 {
indented.push_str(line);
} else {
indented.push('\n');
indented.push_str(indentation);
indented.push_str(line);
}
}
diagnostic.amend(Fix::replacement(
indented,
stmt.location,
stmt.end_location.unwrap(),
));
}
}
checker.diagnostics.push(diagnostic);
}
}
}
fn is_ambiguous_name(name: &str) -> bool {
name == "l" || name == "I" || name == "O"
}
/// E741
pub fn ambiguous_variable_name(name: &str, range: Range) -> Option<Diagnostic> {
if is_ambiguous_name(name) {
Some(Diagnostic::new(
violations::AmbiguousVariableName(name.to_string()),
range,
))
} else {
None
}
}
/// E742
pub fn ambiguous_class_name<F>(name: &str, locate: F) -> Option<Diagnostic>
where
F: FnOnce() -> Range,
{
if is_ambiguous_name(name) {
Some(Diagnostic::new(
violations::AmbiguousClassName(name.to_string()),
locate(),
))
} else {
None
}
}
/// E743
pub fn ambiguous_function_name<F>(name: &str, locate: F) -> Option<Diagnostic>
where
F: FnOnce() -> Range,
{
if is_ambiguous_name(name) {
Some(Diagnostic::new(
violations::AmbiguousFunctionName(name.to_string()),
locate(),
))
} else {
None
}
}
/// W292
pub fn no_newline_at_end_of_file(contents: &str, autofix: bool) -> Option<Diagnostic> {
if !contents.ends_with('\n') {
// Note: if `lines.last()` is `None`, then `contents` is empty (and so we don't
// want to raise W292 anyway).
if let Some(line) = contents.lines().last() {
// Both locations are at the end of the file (and thus the same).
let location = Location::new(contents.lines().count(), line.len());
let mut diagnostic = Diagnostic::new(
violations::NoNewLineAtEndOfFile,
Range::new(location, location),
);
if autofix {
diagnostic.amend(Fix::insertion("\n".to_string(), location));
}
return Some(diagnostic);
}
}
None
}
// See: https://docs.python.org/3/reference/lexical_analysis.html#string-and-bytes-literals
const VALID_ESCAPE_SEQUENCES: &[char; 23] = &[
'\n', '\\', '\'', '"', 'a', 'b', 'f', 'n', 'r', 't', 'v', '0', '1', '2', '3', '4', '5', '6',
'7', 'x', // Escape sequences only recognized in string literals
'N', 'u', 'U',
];
/// Return the quotation markers used for a String token.
fn extract_quote(text: &str) -> &str {
for quote in ["'''", "\"\"\"", "'", "\""] {
if text.ends_with(quote) {
return quote;
}
}
panic!("Unable to find quotation mark for String token")
}
/// W605
pub fn invalid_escape_sequence(
locator: &Locator,
start: Location,
end: Location,
autofix: bool,
) -> Vec<Diagnostic> {
let mut diagnostics = vec![];
let text = locator.slice_source_code_range(&Range::new(start, end));
// Determine whether the string is single- or triple-quoted.
let quote = extract_quote(&text);
let quote_pos = text.find(quote).unwrap();
let prefix = text[..quote_pos].to_lowercase();
let body = &text[(quote_pos + quote.len())..(text.len() - quote.len())];
if !prefix.contains('r') {
for (row_offset, line) in body.lines().enumerate() {
let chars: Vec<char> = line.chars().collect();
for col_offset in 0..chars.len() {
if chars[col_offset] != '\\' {
continue;
}
// If the previous character was also a backslash, skip.
if col_offset > 0 && chars[col_offset - 1] == '\\' {
continue;
}
// If we're at the end of the line, skip.
if col_offset == chars.len() - 1 {
continue;
}
// If the next character is a valid escape sequence, skip.
let next_char = chars[col_offset + 1];
if VALID_ESCAPE_SEQUENCES.contains(&next_char) {
continue;
}
// Compute the location of the escape sequence by offsetting the location of the
// string token by the characters we've seen thus far.
let col = if row_offset == 0 {
start.column() + prefix.len() + quote.len() + col_offset
} else {
col_offset
};
let location = Location::new(start.row() + row_offset, col);
let end_location = Location::new(location.row(), location.column() + 2);
let mut diagnostic = Diagnostic::new(
violations::InvalidEscapeSequence(next_char),
Range::new(location, end_location),
);
if autofix {
diagnostic.amend(Fix::insertion(r"\".to_string(), location));
}
diagnostics.push(diagnostic);
}
}
}
diagnostics
}