Bump version to 0.0.36

.pre-commit-config.yaml

@@ -1,5 +1,5 @@
 repos:
   - repo: https://github.com/charliermarsh/ruff
-    rev: v0.0.33
+    rev: v0.0.36
     hooks:
       - id: lint

Cargo.lock

@@ -1744,7 +1744,7 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.0.33"
+version = "0.0.36"
 dependencies = [
  "anyhow",
  "bincode",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff"
-version = "0.0.33"
+version = "0.0.36"
 edition = "2021"
 
 [lib]

README.md

@@ -57,7 +57,7 @@ ruff also works with [Pre-Commit](https://pre-commit.com) (requires Cargo on sys
 ```yaml
 repos:
 - repo: https://github.com/charliermarsh/ruff
-  rev: v0.0.33
+  rev: v0.0.36
   hooks:
     - id: lint
 ```
@@ -86,7 +86,7 @@ ruff path/to/code/ --select F401 F403
 See `ruff --help` for more:
 
 ```shell
-ruff (v0.0.33)
+ruff (v0.0.36)
 An extremely fast Python linter.
 
 USAGE:
@@ -124,13 +124,12 @@ ruff's goal is to achieve feature-parity with Flake8 when used (1) without any p
 stylistic checks; limiting to Python 3 obviates the need for certain compatibility checks.)
 
 Under those conditions, Flake8 implements about 58 rules, give or take. At time of writing, ruff
-implements 28 rules. (Note that these 28 rules likely cover a disproportionate share of errors:
+implements 36 rules. (Note that these 36 rules likely cover a disproportionate share of errors:
 unused imports, undefined variables, etc.)
 
 Of the unimplemented rules, ruff is missing:
 
 - 15 rules related to string `.format` calls.
-- 6 rules related to misplaced `yield`, `break`, and `return` statements.
 - 3 rules related to syntax errors in doctests and annotations.
 - 2 rules related to redefining unused names.
 
@@ -147,15 +146,21 @@ Beyond rule-set parity, ruff suffers from the following limitations vis-à-vis F
 | Code | Name | Message |
 | ---- | ----- | ------- |
 | E402 | ModuleImportNotAtTopOfFile | Module level import not at top of file |
-| E501 | LineTooLong | Line too long |
+| E501 | LineTooLong | Line too long (89 > 88 characters) |
 | E711 | NoneComparison | Comparison to `None` should be `cond is None` |
 | E712 | TrueFalseComparison | Comparison to `True` should be `cond is True` |
 | E713 | NotInTest | Test for membership should be `not in` |
 | E714 | NotIsTest | Test for object identity should be `is not` |
+| E722 | DoNotUseBareExcept | Do not use bare `except` |
 | E731 | DoNotAssignLambda | Do not assign a lambda expression, use a def |
+| E741 | AmbiguousVariableName | ambiguous variable name '...' |
+| E742 | AmbiguousClassName | ambiguous class name '...' |
+| E743 | AmbiguousFunctionName | ambiguous function name '...' |
 | E902 | IOError | No such file or directory: `...` |
 | F401 | UnusedImport | `...` imported but unused |
 | F403 | ImportStarUsage | Unable to detect undefined names |
+| F404 | LateFutureImport | from __future__ imports must occur at the beginning of the file |
+| F407 | FutureFeatureNotDefined | future feature '...' is not defined |
 | F541 | FStringMissingPlaceholders | f-string without any placeholders |
 | F601 | MultiValueRepeatedKeyLiteral | Dictionary key literal repeated |
 | F602 | MultiValueRepeatedKeyVariable | Dictionary key `...` repeated |
@@ -163,6 +168,8 @@ Beyond rule-set parity, ruff suffers from the following limitations vis-à-vis F
 | F622 | TwoStarredExpressions | two starred expressions in assignment |
 | F631 | AssertTuple | Assert test is a non-empty tuple, which is always `True` |
 | F634 | IfTuple | If test is a tuple, which is always `True` |
+| F701 | BreakOutsideLoop | `break` outside loop |
+| F702 | ContinueOutsideLoop | `continue` not properly in loop |
 | F704 | YieldOutsideFunction | a `yield` or `yield from` statement outside of a function/method |
 | F706 | ReturnOutsideFunction | a `return` statement outside of a function/method |
 | F707 | DefaultExceptNotLast | an `except:` block as not the last exception handler |

examples/generate_rules_table.rs

@@ -3,15 +3,23 @@ use ruff::checks::{CheckKind, RejectedCmpop};
 
 fn main() {
     let mut check_kinds: Vec<CheckKind> = vec![
+        CheckKind::AmbiguousClassName("...".to_string()),
+        CheckKind::AmbiguousFunctionName("...".to_string()),
+        CheckKind::AmbiguousVariableName("...".to_string()),
         CheckKind::AssertTuple,
+        CheckKind::BreakOutsideLoop,
+        CheckKind::ContinueOutsideLoop,
         CheckKind::DefaultExceptNotLast,
         CheckKind::DoNotAssignLambda,
+        CheckKind::DoNotUseBareExcept,
         CheckKind::DuplicateArgumentName,
         CheckKind::FStringMissingPlaceholders,
+        CheckKind::FutureFeatureNotDefined("...".to_string()),
         CheckKind::IOError("...".to_string()),
         CheckKind::IfTuple,
         CheckKind::ImportStarUsage,
-        CheckKind::LineTooLong,
+        CheckKind::LateFutureImport,
+        CheckKind::LineTooLong(89, 88),
         CheckKind::ModuleImportNotAtTopOfFile,
         CheckKind::MultiValueRepeatedKeyLiteral,
         CheckKind::MultiValueRepeatedKeyVariable("...".to_string()),

resources/test/fixtures/E722.py

@@ -0,0 +1,9 @@
+try:
+    pass
+except:
+    pass
+
+try:
+    pass
+except Exception:
+    pass

resources/test/fixtures/E741.py

@@ -0,0 +1,75 @@
+from contextlib import contextmanager
+
+l = 0
+I = 0
+O = 0
+l: int = 0
+
+a, l = 0, 1
+[a, l] = 0, 1
+a, *l = 0, 1, 2
+a = l = 0
+
+o = 0
+i = 0
+
+for l in range(3):
+    pass
+
+
+for a, l in zip(range(3), range(3)):
+    pass
+
+
+def f1():
+    global l
+    l = 0
+
+
+def f2():
+    l = 0
+
+    def f3():
+        nonlocal l
+        l = 1
+
+    f3()
+    return l
+
+
+def f4(l, /, I):
+    return l, I, O
+
+
+def f5(l=0, *, I=1):
+    return l, I
+
+
+def f6(*l, **I):
+    return l, I
+
+
+@contextmanager
+def ctx1():
+    yield 0
+
+
+with ctx1() as l:
+    pass
+
+
+@contextmanager
+def ctx2():
+    yield 0, 1
+
+
+with ctx2() as (a, l):
+    pass
+
+try:
+    pass
+except ValueError as l:
+    pass
+
+if (l := 5) > 0:
+    pass

resources/test/fixtures/E742.py

@@ -0,0 +1,14 @@
+class l:
+    pass
+
+
+class I:
+    pass
+
+
+class O:
+    pass
+
+
+class X:
+    pass

resources/test/fixtures/E743.py

@@ -0,0 +1,15 @@
+def l():
+    pass
+
+
+def I():
+    pass
+
+
+class X:
+    def O(self):
+        pass
+
+
+def x():
+    pass

resources/test/fixtures/F404.py

@@ -0,0 +1,7 @@
+from __future__ import print_function
+"""Docstring"""
+from __future__ import absolute_import
+
+from collections import namedtuple
+
+from __future__ import print_function

resources/test/fixtures/F407.py

@@ -0,0 +1,2 @@
+from __future__ import print_function
+from __future__ import non_existent_feature

resources/test/fixtures/F701.py

@@ -0,0 +1,23 @@
+for i in range(10):
+    break
+else:
+    break
+
+i = 0
+while i < 10:
+    i += 1
+    break
+
+
+def f():
+    for i in range(10):
+        break
+
+    break
+
+
+class Foo:
+    break
+
+
+break

resources/test/fixtures/F702.py

@@ -0,0 +1,23 @@
+for i in range(10):
+    continue
+else:
+    continue
+
+i = 0
+while i < 10:
+    i += 1
+    continue
+
+
+def f():
+    for i in range(10):
+        continue
+
+    continue
+
+
+class Foo:
+    continue
+
+
+continue

resources/test/fixtures/F841.py

@@ -14,3 +14,11 @@ def f():
     x = 1
     y = 2
     z = x + y
+
+
+def g():
+    foo = (1, 2)
+    (a, b) = (1, 2)
+
+    bar = (1, 2)
+    (c, d) = bar

resources/test/fixtures/pyproject.toml

@@ -8,10 +8,16 @@ select = [
     "E712",
     "E713",
     "E714",
+    "E722",
     "E731",
+    "E741",
+    "E742",
+    "E743",
     "E902",
     "F401",
     "F403",
+    "F404",
+    "F407",
     "F541",
     "F601",
     "F602",
@@ -19,6 +25,8 @@ select = [
     "F622",
     "F631",
     "F634",
+    "F701",
+    "F702",
     "F704",
     "F706",
     "F707",

src/ast/checks.rs

@@ -3,7 +3,7 @@ use std::collections::BTreeSet;
 use itertools::izip;
 use rustpython_parser::ast::{
     Arg, Arguments, Cmpop, Constant, Excepthandler, ExcepthandlerKind, Expr, ExprKind, Keyword,
-    Location, Stmt, Unaryop,
+    Location, Stmt, StmtKind, Unaryop,
 };
 
 use crate::ast::operations::SourceCodeLocator;
@@ -93,6 +93,46 @@ pub fn check_do_not_assign_lambda(value: &Expr, location: Location) -> Option<Ch
     }
 }
 
+fn is_ambiguous_name(name: &str) -> bool {
+    name == "l" || name == "I" || name == "O"
+}
+
+/// Check AmbiguousVariableName compliance.
+pub fn check_ambiguous_variable_name(name: &str, location: Location) -> Option<Check> {
+    if is_ambiguous_name(name) {
+        Some(Check::new(
+            CheckKind::AmbiguousVariableName(name.to_string()),
+            location,
+        ))
+    } else {
+        None
+    }
+}
+
+/// Check AmbiguousClassName compliance.
+pub fn check_ambiguous_class_name(name: &str, location: Location) -> Option<Check> {
+    if is_ambiguous_name(name) {
+        Some(Check::new(
+            CheckKind::AmbiguousClassName(name.to_string()),
+            location,
+        ))
+    } else {
+        None
+    }
+}
+
+/// Check AmbiguousFunctionName compliance.
+pub fn check_ambiguous_function_name(name: &str, location: Location) -> Option<Check> {
+    if is_ambiguous_name(name) {
+        Some(Check::new(
+            CheckKind::AmbiguousFunctionName(name.to_string()),
+            location,
+        ))
+    } else {
+        None
+    }
+}
+
 /// Check UselessObjectInheritance compliance.
 pub fn check_useless_object_inheritance(
     stmt: &Stmt,
@@ -428,3 +468,77 @@ pub fn check_starred_expressions(
 
     None
 }
+
+/// Check BreakOutsideLoop compliance.
+pub fn check_break_outside_loop(
+    stmt: &Stmt,
+    parents: &[&Stmt],
+    parent_stack: &[usize],
+) -> Option<Check> {
+    let mut allowed: bool = false;
+    let mut parent = stmt;
+    for index in parent_stack.iter().rev() {
+        let child = parent;
+        parent = parents[*index];
+        match &parent.node {
+            StmtKind::For { orelse, .. }
+            | StmtKind::AsyncFor { orelse, .. }
+            | StmtKind::While { orelse, .. } => {
+                if !orelse.contains(child) {
+                    allowed = true;
+                    break;
+                }
+            }
+
+            StmtKind::FunctionDef { .. }
+            | StmtKind::AsyncFunctionDef { .. }
+            | StmtKind::ClassDef { .. } => {
+                break;
+            }
+            _ => {}
+        }
+    }
+
+    if !allowed {
+        Some(Check::new(CheckKind::BreakOutsideLoop, stmt.location))
+    } else {
+        None
+    }
+}
+
+/// Check ContinueOutsideLoop compliance.
+pub fn check_continue_outside_loop(
+    stmt: &Stmt,
+    parents: &[&Stmt],
+    parent_stack: &[usize],
+) -> Option<Check> {
+    let mut allowed: bool = false;
+    let mut parent = stmt;
+    for index in parent_stack.iter().rev() {
+        let child = parent;
+        parent = parents[*index];
+        match &parent.node {
+            StmtKind::For { orelse, .. }
+            | StmtKind::AsyncFor { orelse, .. }
+            | StmtKind::While { orelse, .. } => {
+                if !orelse.contains(child) {
+                    allowed = true;
+                    break;
+                }
+            }
+
+            StmtKind::FunctionDef { .. }
+            | StmtKind::AsyncFunctionDef { .. }
+            | StmtKind::ClassDef { .. } => {
+                break;
+            }
+            _ => {}
+        }
+    }
+
+    if !allowed {
+        Some(Check::new(CheckKind::ContinueOutsideLoop, stmt.location))
+    } else {
+        None
+    }
+}

src/ast/operations.rs

@@ -100,6 +100,24 @@ pub fn in_nested_block(parent_stack: &[usize], parents: &[&Stmt]) -> bool {
     false
 }
 
+/// Check if a node represents an unpacking assignment.
+pub fn is_unpacking_assignment(stmt: &Stmt) -> bool {
+    if let StmtKind::Assign { targets, value, .. } = &stmt.node {
+        for child in targets {
+            match &child.node {
+                ExprKind::Set { .. } | ExprKind::List { .. } | ExprKind::Tuple { .. } => {}
+                _ => return false,
+            }
+        }
+        match &value.node {
+            ExprKind::Set { .. } | ExprKind::List { .. } | ExprKind::Tuple { .. } => return false,
+            _ => {}
+        }
+        return true;
+    }
+    false
+}
+
 /// Struct used to efficiently slice source code at (row, column) Locations.
 pub struct SourceCodeLocator<'a> {
     content: &'a str,

src/ast/types.rs

@@ -35,8 +35,10 @@ impl Scope {
 
 #[derive(Clone, Debug)]
 pub enum BindingKind {
+    Annotation,
     Argument,
     Assignment,
+    Binding,
     Builtin,
     ClassDefinition,
     Definition,

src/check_ast.rs

@@ -1,3 +1,4 @@
+use std::ops::Deref;
 use std::path::Path;
 
 use rustpython_parser::ast::{
@@ -14,6 +15,7 @@ use crate::ast::{checks, operations, visitor};
 use crate::autofix::fixer;
 use crate::checks::{Check, CheckCode, CheckKind};
 use crate::python::builtins::{BUILTINS, MAGIC_GLOBALS};
+use crate::python::future::ALL_FEATURE_NAMES;
 use crate::python::typing;
 use crate::settings::Settings;
 
@@ -44,6 +46,7 @@ struct Checker<'a> {
     in_literal: bool,
     seen_non_import: bool,
     seen_docstring: bool,
+    futures_allowed: bool,
 }
 
 impl<'a> Checker<'a> {
@@ -73,6 +76,7 @@ impl<'a> Checker<'a> {
             in_literal: false,
             seen_non_import: false,
             seen_docstring: false,
+            futures_allowed: true,
         }
     }
 }
@@ -102,32 +106,57 @@ where
 
         // Track whether we've seen docstrings, non-imports, etc.
         match &stmt.node {
-            StmtKind::Import { .. } => {}
-            StmtKind::ImportFrom { .. } => {}
-            StmtKind::Expr { value } => {
-                if !self.seen_docstring
-                    && stmt.location.column() == 1
-                    && !operations::in_nested_block(&self.parent_stack, &self.parents)
-                {
-                    if let ExprKind::Constant {
-                        value: Constant::Str(_),
-                        ..
-                    } = &value.node
-                    {
-                        self.seen_docstring = true;
+            StmtKind::ImportFrom { module, .. } => {
+                // Allow __future__ imports until we see a non-__future__ import.
+                if self.futures_allowed {
+                    if let Some(module) = module {
+                        if module != "__future__" {
+                            self.futures_allowed = false;
+                        }
                     }
                 }
-
-                if !self.seen_non_import
-                    && stmt.location.column() == 1
+            }
+            StmtKind::Import { .. } => {
+                self.futures_allowed = false;
+            }
+            StmtKind::Expr { value } => {
+                if self.seen_docstring
+                    && !self.seen_non_import
                     && !operations::in_nested_block(&self.parent_stack, &self.parents)
                 {
                     self.seen_non_import = true;
                 }
+
+                if !self.seen_docstring
+                    && !operations::in_nested_block(&self.parent_stack, &self.parents)
+                    && matches!(
+                        &value.node,
+                        ExprKind::Constant {
+                            value: Constant::Str(_),
+                            ..
+                        },
+                    )
+                {
+                    self.seen_docstring = true;
+                }
+
+                // Allow docstrings to interrupt __future__ imports.
+                if self.futures_allowed
+                    && !matches!(
+                        &value.node,
+                        ExprKind::Constant {
+                            value: Constant::Str(_),
+                            ..
+                        },
+                    )
+                {
+                    self.futures_allowed = false;
+                }
             }
             _ => {
+                self.futures_allowed = false;
+
                 if !self.seen_non_import
-                    && stmt.location.column() == 1
                     && !operations::in_nested_block(&self.parent_stack, &self.parents)
                 {
                     self.seen_non_import = true;
@@ -158,6 +187,30 @@ where
                         }
                     }
                 }
+
+                if self.settings.select.contains(&CheckCode::E741) {
+                    self.checks.extend(names.iter().filter_map(|name| {
+                        checks::check_ambiguous_variable_name(name, stmt.location)
+                    }));
+                }
+            }
+            StmtKind::Break => {
+                if self.settings.select.contains(&CheckCode::F701) {
+                    if let Some(check) =
+                        checks::check_break_outside_loop(stmt, &self.parents, &self.parent_stack)
+                    {
+                        self.checks.push(check);
+                    }
+                }
+            }
+            StmtKind::Continue => {
+                if self.settings.select.contains(&CheckCode::F702) {
+                    if let Some(check) =
+                        checks::check_continue_outside_loop(stmt, &self.parents, &self.parent_stack)
+                    {
+                        self.checks.push(check);
+                    }
+                }
             }
             StmtKind::FunctionDef {
                 name,
@@ -173,6 +226,12 @@ where
                 args,
                 ..
             } => {
+                if self.settings.select.contains(&CheckCode::E743) {
+                    if let Some(check) = checks::check_ambiguous_function_name(name, stmt.location)
+                    {
+                        self.checks.push(check);
+                    }
+                }
                 for expr in decorator_list {
                     self.visit_expr(expr);
                 }
@@ -261,6 +320,12 @@ where
                     }
                 }
 
+                if self.settings.select.contains(&CheckCode::E742) {
+                    if let Some(check) = checks::check_ambiguous_class_name(name, stmt.location) {
+                        self.checks.push(check);
+                    }
+                }
+
                 for expr in bases {
                     self.visit_expr(expr)
                 }
@@ -357,6 +422,21 @@ where
                                 location: stmt.location,
                             },
                         );
+
+                        if self.settings.select.contains(&CheckCode::F407)
+                            && !ALL_FEATURE_NAMES.contains(&alias.node.name.deref())
+                        {
+                            self.checks.push(Check::new(
+                                CheckKind::FutureFeatureNotDefined(alias.node.name.to_string()),
+                                stmt.location,
+                            ));
+                        }
+
+                        if self.settings.select.contains(&CheckCode::F404) && !self.futures_allowed
+                        {
+                            self.checks
+                                .push(Check::new(CheckKind::LateFutureImport, stmt.location));
+                        }
                     } else if alias.node.name == "*" {
                         self.add_binding(
                             name,
@@ -491,7 +571,7 @@ where
                     self.in_literal = true;
                 }
             }
-            ExprKind::Tuple { elts, ctx } => {
+            ExprKind::Tuple { elts, ctx } | ExprKind::List { elts, ctx } => {
                 if matches!(ctx, ExprContext::Store) {
                     let check_too_many_expressions =
                         self.settings.select.contains(&CheckCode::F621);
@@ -507,12 +587,19 @@ where
                     }
                 }
             }
-            ExprKind::Name { ctx, .. } => match ctx {
+            ExprKind::Name { id, ctx } => match ctx {
                 ExprContext::Load => self.handle_node_load(expr),
                 ExprContext::Store => {
+                    if self.settings.select.contains(&CheckCode::E741) {
+                        if let Some(check) =
+                            checks::check_ambiguous_variable_name(id, expr.location)
+                        {
+                            self.checks.push(check);
+                        }
+                    }
                     let parent =
                         self.parents[*(self.parent_stack.last().expect("No parent found."))];
-                    self.handle_node_store(expr, Some(parent));
+                    self.handle_node_store(expr, parent);
                 }
                 ExprContext::Del => self.handle_node_delete(expr),
             },
@@ -744,13 +831,45 @@ where
 
     fn visit_excepthandler(&mut self, excepthandler: &'b Excepthandler) {
         match &excepthandler.node {
-            ExcepthandlerKind::ExceptHandler { name, .. } => match name {
-                Some(name) => {
-                    let scope =
-                        &self.scopes[*(self.scope_stack.last().expect("No current scope found."))];
-                    if scope.values.contains_key(name) {
+            ExcepthandlerKind::ExceptHandler { type_, name, .. } => {
+                if self.settings.select.contains(&CheckCode::E722) && type_.is_none() {
+                    self.checks.push(Check::new(
+                        CheckKind::DoNotUseBareExcept,
+                        excepthandler.location,
+                    ));
+                }
+                match name {
+                    Some(name) => {
+                        if self.settings.select.contains(&CheckCode::E741) {
+                            if let Some(check) =
+                                checks::check_ambiguous_variable_name(name, excepthandler.location)
+                            {
+                                self.checks.push(check);
+                            }
+                        }
+                        let scope = &self.scopes
+                            [*(self.scope_stack.last().expect("No current scope found."))];
+                        if scope.values.contains_key(name) {
+                            let parent = self.parents
+                                [*(self.parent_stack.last().expect("No parent found."))];
+                            self.handle_node_store(
+                                &Expr::new(
+                                    excepthandler.location,
+                                    ExprKind::Name {
+                                        id: name.to_string(),
+                                        ctx: ExprContext::Store,
+                                    },
+                                ),
+                                parent,
+                            );
+                            self.parents.push(parent);
+                        }
+
                         let parent =
                             self.parents[*(self.parent_stack.last().expect("No parent found."))];
+                        let scope = &self.scopes
+                            [*(self.scope_stack.last().expect("No current scope found."))];
+                        let definition = scope.values.get(name).cloned();
                         self.handle_node_store(
                             &Expr::new(
                                 excepthandler.location,
@@ -759,48 +878,32 @@ where
                                     ctx: ExprContext::Store,
                                 },
                             ),
-                            Some(parent),
+                            parent,
                         );
                         self.parents.push(parent);
-                    }
 
-                    let parent =
-                        self.parents[*(self.parent_stack.last().expect("No parent found."))];
-                    let scope =
-                        &self.scopes[*(self.scope_stack.last().expect("No current scope found."))];
-                    let definition = scope.values.get(name).cloned();
-                    self.handle_node_store(
-                        &Expr::new(
-                            excepthandler.location,
-                            ExprKind::Name {
-                                id: name.to_string(),
-                                ctx: ExprContext::Store,
-                            },
-                        ),
-                        Some(parent),
-                    );
-                    self.parents.push(parent);
+                        walk_excepthandler(self, excepthandler);
 
-                    walk_excepthandler(self, excepthandler);
+                        let scope = &mut self.scopes
+                            [*(self.scope_stack.last().expect("No current scope found."))];
+                        if let Some(binding) = &scope.values.remove(name) {
+                            if self.settings.select.contains(&CheckCode::F841)
+                                && binding.used.is_none()
+                            {
+                                self.checks.push(Check::new(
+                                    CheckKind::UnusedVariable(name.to_string()),
+                                    excepthandler.location,
+                                ));
+                            }
+                        }
 
-                    let scope = &mut self.scopes
-                        [*(self.scope_stack.last().expect("No current scope found."))];
-                    if let Some(binding) = &scope.values.remove(name) {
-                        if self.settings.select.contains(&CheckCode::F841) && binding.used.is_none()
-                        {
-                            self.checks.push(Check::new(
-                                CheckKind::UnusedVariable(name.to_string()),
-                                excepthandler.location,
-                            ));
+                        if let Some(binding) = definition {
+                            scope.values.insert(name.to_string(), binding);
                         }
                     }
-
-                    if let Some(binding) = definition {
-                        scope.values.insert(name.to_string(), binding);
-                    }
+                    None => walk_excepthandler(self, excepthandler),
                 }
-                None => walk_excepthandler(self, excepthandler),
-            },
+            }
         }
     }
 
@@ -838,6 +941,13 @@ where
                 location: arg.location,
             },
         );
+
+        if self.settings.select.contains(&CheckCode::E741) {
+            if let Some(check) = checks::check_ambiguous_variable_name(&arg.node.arg, arg.location)
+            {
+                self.checks.push(check);
+            }
+        }
     }
 }
 
@@ -940,7 +1050,7 @@ impl<'a> Checker<'a> {
         }
     }
 
-    fn handle_node_store(&mut self, expr: &Expr, parent: Option<&Stmt>) {
+    fn handle_node_store(&mut self, expr: &Expr, parent: &Stmt) {
         if let ExprKind::Name { id, .. } = &expr.node {
             let current =
                 &self.scopes[*(self.scope_stack.last().expect("No current scope found."))];
@@ -970,35 +1080,59 @@ impl<'a> Checker<'a> {
                 }
             }
 
-            // TODO(charlie): Handle alternate binding types (like `Annotation`).
-            if id == "__all__"
-                && matches!(current.kind, ScopeKind::Module)
-                && parent
-                    .map(|stmt| {
-                        matches!(stmt.node, StmtKind::Assign { .. })
-                            || matches!(stmt.node, StmtKind::AugAssign { .. })
-                            || matches!(stmt.node, StmtKind::AnnAssign { .. })
-                    })
-                    .unwrap_or_default()
+            if matches!(parent.node, StmtKind::AnnAssign { value: None, .. }) {
+                self.add_binding(
+                    id.to_string(),
+                    Binding {
+                        kind: BindingKind::Annotation,
+                        used: None,
+                        location: expr.location,
+                    },
+                );
+                return;
+            }
+
+            // TODO(charlie): Include comprehensions here.
+            if matches!(parent.node, StmtKind::For { .. })
+                || matches!(parent.node, StmtKind::AsyncFor { .. })
+                || operations::is_unpacking_assignment(parent)
             {
                 self.add_binding(
                     id.to_string(),
                     Binding {
-                        kind: BindingKind::Export(extract_all_names(parent.unwrap(), current)),
+                        kind: BindingKind::Binding,
                         used: None,
                         location: expr.location,
                     },
                 );
-            } else {
+                return;
+            }
+
+            if id == "__all__"
+                && matches!(current.kind, ScopeKind::Module)
+                && (matches!(parent.node, StmtKind::Assign { .. })
+                    || matches!(parent.node, StmtKind::AugAssign { .. })
+                    || matches!(parent.node, StmtKind::AnnAssign { .. }))
+            {
                 self.add_binding(
                     id.to_string(),
                     Binding {
-                        kind: BindingKind::Assignment,
+                        kind: BindingKind::Export(extract_all_names(parent, current)),
                         used: None,
                         location: expr.location,
                     },
                 );
+                return;
             }
+
+            self.add_binding(
+                id.to_string(),
+                Binding {
+                    kind: BindingKind::Assignment,
+                    used: None,
+                    location: expr.location,
+                },
+            );
         }
     }
 

src/check_lines.rs

@@ -1,11 +1,11 @@
 use rustpython_parser::ast::Location;
 
-use crate::checks::{Check, CheckKind};
+use crate::checks::{Check, CheckCode, CheckKind};
 use crate::settings::Settings;
 
 /// Whether the given line is too long and should be reported.
-fn should_enforce_line_length(line: &str, limit: usize) -> bool {
-    if line.len() > limit {
+fn should_enforce_line_length(line: &str, length: usize, limit: usize) -> bool {
+    if length > limit {
         let mut chunks = line.split_whitespace();
         if let (Some(first), Some(_)) = (chunks.next(), chunks.next()) {
             // Do not enforce the line length for commented lines with a single word
@@ -20,7 +20,7 @@ fn should_enforce_line_length(line: &str, limit: usize) -> bool {
 }
 
 pub fn check_lines(checks: &mut Vec<Check>, contents: &str, settings: &Settings) {
-    let enforce_line_too_long = settings.select.contains(CheckKind::LineTooLong.code());
+    let enforce_line_too_long = settings.select.contains(&CheckCode::E501);
 
     let mut line_checks = vec![];
     let mut ignored = vec![];
@@ -34,13 +34,16 @@ pub fn check_lines(checks: &mut Vec<Check>, contents: &str, settings: &Settings)
         }
 
         // Enforce line length.
-        if enforce_line_too_long && should_enforce_line_length(line, settings.line_length) {
-            let check = Check::new(
-                CheckKind::LineTooLong,
-                Location::new(row + 1, settings.line_length + 1),
-            );
-            if !check.is_inline_ignored(line) {
-                line_checks.push(check);
+        if enforce_line_too_long {
+            let line_length = line.len();
+            if should_enforce_line_length(line, line_length, settings.line_length) {
+                let check = Check::new(
+                    CheckKind::LineTooLong(line_length, settings.line_length),
+                    Location::new(row + 1, settings.line_length + 1),
+                );
+                if !check.is_inline_ignored(line) {
+                    line_checks.push(check);
+                }
             }
         }
     }

src/checks.rs

@@ -14,10 +14,16 @@ pub enum CheckCode {
     E712,
     E713,
     E714,
+    E722,
     E731,
+    E741,
+    E742,
+    E743,
     E902,
     F401,
     F403,
+    F404,
+    F407,
     F541,
     F601,
     F602,
@@ -25,6 +31,8 @@ pub enum CheckCode {
     F622,
     F631,
     F634,
+    F701,
+    F702,
     F704,
     F706,
     F707,
@@ -48,11 +56,17 @@ impl FromStr for CheckCode {
             "E711" => Ok(CheckCode::E711),
             "E712" => Ok(CheckCode::E712),
             "E713" => Ok(CheckCode::E713),
+            "E722" => Ok(CheckCode::E722),
             "E714" => Ok(CheckCode::E714),
             "E731" => Ok(CheckCode::E731),
+            "E741" => Ok(CheckCode::E741),
+            "E742" => Ok(CheckCode::E742),
+            "E743" => Ok(CheckCode::E743),
             "E902" => Ok(CheckCode::E902),
             "F401" => Ok(CheckCode::F401),
             "F403" => Ok(CheckCode::F403),
+            "F404" => Ok(CheckCode::F404),
+            "F407" => Ok(CheckCode::F407),
             "F541" => Ok(CheckCode::F541),
             "F601" => Ok(CheckCode::F601),
             "F602" => Ok(CheckCode::F602),
@@ -60,6 +74,8 @@ impl FromStr for CheckCode {
             "F622" => Ok(CheckCode::F622),
             "F631" => Ok(CheckCode::F631),
             "F634" => Ok(CheckCode::F634),
+            "F701" => Ok(CheckCode::F701),
+            "F702" => Ok(CheckCode::F702),
             "F704" => Ok(CheckCode::F704),
             "F706" => Ok(CheckCode::F706),
             "F707" => Ok(CheckCode::F707),
@@ -85,10 +101,16 @@ impl CheckCode {
             CheckCode::E712 => "E712",
             CheckCode::E713 => "E713",
             CheckCode::E714 => "E714",
+            CheckCode::E722 => "E722",
             CheckCode::E731 => "E731",
+            CheckCode::E741 => "E741",
+            CheckCode::E742 => "E742",
+            CheckCode::E743 => "E743",
             CheckCode::E902 => "E902",
             CheckCode::F401 => "F401",
             CheckCode::F403 => "F403",
+            CheckCode::F404 => "F404",
+            CheckCode::F407 => "F407",
             CheckCode::F541 => "F541",
             CheckCode::F601 => "F601",
             CheckCode::F602 => "F602",
@@ -96,6 +118,8 @@ impl CheckCode {
             CheckCode::F622 => "F622",
             CheckCode::F631 => "F631",
             CheckCode::F634 => "F634",
+            CheckCode::F701 => "F701",
+            CheckCode::F702 => "F702",
             CheckCode::F704 => "F704",
             CheckCode::F706 => "F706",
             CheckCode::F707 => "F707",
@@ -119,10 +143,16 @@ impl CheckCode {
             CheckCode::E712 => &LintSource::AST,
             CheckCode::E713 => &LintSource::AST,
             CheckCode::E714 => &LintSource::AST,
+            CheckCode::E722 => &LintSource::AST,
             CheckCode::E731 => &LintSource::AST,
+            CheckCode::E741 => &LintSource::AST,
+            CheckCode::E742 => &LintSource::AST,
+            CheckCode::E743 => &LintSource::AST,
             CheckCode::E902 => &LintSource::FileSystem,
             CheckCode::F401 => &LintSource::AST,
             CheckCode::F403 => &LintSource::AST,
+            CheckCode::F404 => &LintSource::AST,
+            CheckCode::F407 => &LintSource::AST,
             CheckCode::F541 => &LintSource::AST,
             CheckCode::F601 => &LintSource::AST,
             CheckCode::F602 => &LintSource::AST,
@@ -130,6 +160,8 @@ impl CheckCode {
             CheckCode::F622 => &LintSource::AST,
             CheckCode::F631 => &LintSource::AST,
             CheckCode::F634 => &LintSource::AST,
+            CheckCode::F701 => &LintSource::AST,
+            CheckCode::F702 => &LintSource::AST,
             CheckCode::F704 => &LintSource::AST,
             CheckCode::F706 => &LintSource::AST,
             CheckCode::F707 => &LintSource::AST,
@@ -160,15 +192,23 @@ pub enum RejectedCmpop {
 
 #[derive(Debug, PartialEq, Eq, Serialize, Deserialize)]
 pub enum CheckKind {
+    AmbiguousClassName(String),
+    AmbiguousFunctionName(String),
+    AmbiguousVariableName(String),
     AssertTuple,
+    BreakOutsideLoop,
+    ContinueOutsideLoop,
     DefaultExceptNotLast,
     DoNotAssignLambda,
+    DoNotUseBareExcept,
     DuplicateArgumentName,
     FStringMissingPlaceholders,
+    FutureFeatureNotDefined(String),
     IOError(String),
     IfTuple,
     ImportStarUsage,
-    LineTooLong,
+    LateFutureImport,
+    LineTooLong(usize, usize),
     ModuleImportNotAtTopOfFile,
     MultiValueRepeatedKeyLiteral,
     MultiValueRepeatedKeyVariable(String),
@@ -194,15 +234,23 @@ impl CheckKind {
     /// The name of the check.
     pub fn name(&self) -> &'static str {
         match self {
+            CheckKind::AmbiguousClassName(_) => "AmbiguousClassName",
+            CheckKind::AmbiguousFunctionName(_) => "AmbiguousFunctionName",
+            CheckKind::AmbiguousVariableName(_) => "AmbiguousVariableName",
             CheckKind::AssertTuple => "AssertTuple",
+            CheckKind::BreakOutsideLoop => "BreakOutsideLoop",
+            CheckKind::ContinueOutsideLoop => "ContinueOutsideLoop",
             CheckKind::DefaultExceptNotLast => "DefaultExceptNotLast",
+            CheckKind::DoNotAssignLambda => "DoNotAssignLambda",
+            CheckKind::DoNotUseBareExcept => "DoNotUseBareExcept",
             CheckKind::DuplicateArgumentName => "DuplicateArgumentName",
             CheckKind::FStringMissingPlaceholders => "FStringMissingPlaceholders",
+            CheckKind::FutureFeatureNotDefined(_) => "FutureFeatureNotDefined",
             CheckKind::IOError(_) => "IOError",
             CheckKind::IfTuple => "IfTuple",
             CheckKind::ImportStarUsage => "ImportStarUsage",
-            CheckKind::LineTooLong => "LineTooLong",
-            CheckKind::DoNotAssignLambda => "DoNotAssignLambda",
+            CheckKind::LateFutureImport => "LateFutureImport",
+            CheckKind::LineTooLong(_, _) => "LineTooLong",
             CheckKind::ModuleImportNotAtTopOfFile => "ModuleImportNotAtTopOfFile",
             CheckKind::MultiValueRepeatedKeyLiteral => "MultiValueRepeatedKeyLiteral",
             CheckKind::MultiValueRepeatedKeyVariable(_) => "MultiValueRepeatedKeyVariable",
@@ -230,15 +278,23 @@ impl CheckKind {
     /// A four-letter shorthand code for the check.
     pub fn code(&self) -> &'static CheckCode {
         match self {
+            CheckKind::AmbiguousClassName(_) => &CheckCode::E742,
+            CheckKind::AmbiguousFunctionName(_) => &CheckCode::E743,
+            CheckKind::AmbiguousVariableName(_) => &CheckCode::E741,
             CheckKind::AssertTuple => &CheckCode::F631,
+            CheckKind::BreakOutsideLoop => &CheckCode::F701,
+            CheckKind::ContinueOutsideLoop => &CheckCode::F702,
             CheckKind::DefaultExceptNotLast => &CheckCode::F707,
+            CheckKind::DoNotAssignLambda => &CheckCode::E731,
+            CheckKind::DoNotUseBareExcept => &CheckCode::E722,
             CheckKind::DuplicateArgumentName => &CheckCode::F831,
             CheckKind::FStringMissingPlaceholders => &CheckCode::F541,
+            CheckKind::FutureFeatureNotDefined(_) => &CheckCode::F407,
             CheckKind::IOError(_) => &CheckCode::E902,
             CheckKind::IfTuple => &CheckCode::F634,
             CheckKind::ImportStarUsage => &CheckCode::F403,
-            CheckKind::LineTooLong => &CheckCode::E501,
-            CheckKind::DoNotAssignLambda => &CheckCode::E731,
+            CheckKind::LateFutureImport => &CheckCode::F404,
+            CheckKind::LineTooLong(_, _) => &CheckCode::E501,
             CheckKind::ModuleImportNotAtTopOfFile => &CheckCode::E402,
             CheckKind::MultiValueRepeatedKeyLiteral => &CheckCode::F601,
             CheckKind::MultiValueRepeatedKeyVariable(_) => &CheckCode::F602,
@@ -264,26 +320,46 @@ impl CheckKind {
     /// The body text for the check.
     pub fn body(&self) -> String {
         match self {
+            CheckKind::AmbiguousClassName(name) => {
+                format!("ambiguous class name '{}'", name)
+            }
+            CheckKind::AmbiguousFunctionName(name) => {
+                format!("ambiguous function name '{}'", name)
+            }
+            CheckKind::AmbiguousVariableName(name) => {
+                format!("ambiguous variable name '{}'", name)
+            }
             CheckKind::AssertTuple => {
                 "Assert test is a non-empty tuple, which is always `True`".to_string()
             }
+            CheckKind::BreakOutsideLoop => "`break` outside loop".to_string(),
+            CheckKind::ContinueOutsideLoop => "`continue` not properly in loop".to_string(),
             CheckKind::DefaultExceptNotLast => {
                 "an `except:` block as not the last exception handler".to_string()
             }
+            CheckKind::DoNotAssignLambda => {
+                "Do not assign a lambda expression, use a def".to_string()
+            }
+            CheckKind::DoNotUseBareExcept => "Do not use bare `except`".to_string(),
             CheckKind::DuplicateArgumentName => {
                 "Duplicate argument name in function definition".to_string()
             }
             CheckKind::FStringMissingPlaceholders => {
                 "f-string without any placeholders".to_string()
             }
+            CheckKind::FutureFeatureNotDefined(name) => {
+                format!("future feature '{name}' is not defined")
+            }
             CheckKind::IOError(name) => {
                 format!("No such file or directory: `{name}`")
             }
             CheckKind::IfTuple => "If test is a tuple, which is always `True`".to_string(),
             CheckKind::ImportStarUsage => "Unable to detect undefined names".to_string(),
-            CheckKind::LineTooLong => "Line too long".to_string(),
-            CheckKind::DoNotAssignLambda => {
-                "Do not assign a lambda expression, use a def".to_string()
+            CheckKind::LateFutureImport => {
+                "from __future__ imports must occur at the beginning of the file".to_string()
+            }
+            CheckKind::LineTooLong(length, limit) => {
+                format!("Line too long ({length} > {limit} characters)")
             }
             CheckKind::ModuleImportNotAtTopOfFile => {
                 "Module level import not at top of file".to_string()
@@ -336,12 +412,12 @@ impl CheckKind {
             CheckKind::UndefinedExport(name) => {
                 format!("Undefined name `{name}` in `__all__`")
             }
-            CheckKind::UndefinedName(name) => {
-                format!("Undefined name `{name}`")
-            }
             CheckKind::UndefinedLocal(name) => {
                 format!("Local variable `{name}` referenced before assignment")
             }
+            CheckKind::UndefinedName(name) => {
+                format!("Undefined name `{name}`")
+            }
             CheckKind::UnusedImport(name) => format!("`{name}` imported but unused"),
             CheckKind::UnusedVariable(name) => {
                 format!("Local variable `{name}` is assigned to but never used")
@@ -357,36 +433,10 @@ impl CheckKind {
 
     /// Whether the check kind is (potentially) fixable.
     pub fn fixable(&self) -> bool {
-        match self {
-            CheckKind::AssertTuple => false,
-            CheckKind::DefaultExceptNotLast => false,
-            CheckKind::DuplicateArgumentName => false,
-            CheckKind::FStringMissingPlaceholders => false,
-            CheckKind::IOError(_) => false,
-            CheckKind::IfTuple => false,
-            CheckKind::ImportStarUsage => false,
-            CheckKind::DoNotAssignLambda => false,
-            CheckKind::LineTooLong => false,
-            CheckKind::ModuleImportNotAtTopOfFile => false,
-            CheckKind::MultiValueRepeatedKeyLiteral => false,
-            CheckKind::MultiValueRepeatedKeyVariable(_) => false,
-            CheckKind::NoAssertEquals => true,
-            CheckKind::NotInTest => false,
-            CheckKind::NotIsTest => false,
-            CheckKind::NoneComparison(_) => false,
-            CheckKind::RaiseNotImplemented => false,
-            CheckKind::ReturnOutsideFunction => false,
-            CheckKind::TooManyExpressionsInStarredAssignment => false,
-            CheckKind::TrueFalseComparison(_, _) => false,
-            CheckKind::TwoStarredExpressions => false,
-            CheckKind::UndefinedExport(_) => false,
-            CheckKind::UndefinedLocal(_) => false,
-            CheckKind::UndefinedName(_) => false,
-            CheckKind::UnusedImport(_) => false,
-            CheckKind::UnusedVariable(_) => false,
-            CheckKind::UselessObjectInheritance(_) => true,
-            CheckKind::YieldOutsideFunction => false,
-        }
+        matches!(
+            self,
+            CheckKind::NoAssertEquals | CheckKind::UselessObjectInheritance(_)
+        )
     }
 }
 

src/linter.rs

@@ -128,7 +128,7 @@ mod tests {
         )?;
         actual.sort_by_key(|check| check.location);
         let expected = vec![Check {
-            kind: CheckKind::LineTooLong,
+            kind: CheckKind::LineTooLong(123, 88),
             location: Location::new(5, 89),
             fix: None,
         }];
@@ -240,6 +240,31 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn e722() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/E722.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::E722]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![Check {
+            kind: CheckKind::DoNotUseBareExcept,
+            location: Location::new(3, 1),
+            fix: None,
+        }];
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
     #[test]
     fn e714() -> Result<()> {
         let mut actual = check_path(
@@ -298,6 +323,230 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn e741() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/E741.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::E741]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(3, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("I".to_string()),
+                location: Location::new(4, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("O".to_string()),
+                location: Location::new(5, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(6, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(8, 4),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(9, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(10, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(11, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(16, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(20, 8),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(25, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(26, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(30, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(33, 9),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(34, 9),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(40, 8),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("I".to_string()),
+                location: Location::new(40, 14),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(44, 8),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("I".to_string()),
+                location: Location::new(44, 16),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(48, 9),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("I".to_string()),
+                location: Location::new(48, 14),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(57, 16),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(66, 20),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(71, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousVariableName("l".to_string()),
+                location: Location::new(74, 5),
+                fix: None,
+            },
+        ];
+
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
+    #[test]
+    fn e742() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/E742.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::E742]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![
+            Check {
+                kind: CheckKind::AmbiguousClassName("l".to_string()),
+                location: Location::new(1, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousClassName("I".to_string()),
+                location: Location::new(5, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousClassName("O".to_string()),
+                location: Location::new(9, 1),
+                fix: None,
+            },
+        ];
+
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
+    #[test]
+    fn e743() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/E743.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::E743]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![
+            Check {
+                kind: CheckKind::AmbiguousFunctionName("l".to_string()),
+                location: Location::new(1, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousFunctionName("I".to_string()),
+                location: Location::new(5, 1),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::AmbiguousFunctionName("O".to_string()),
+                location: Location::new(10, 5),
+                fix: None,
+            },
+        ];
+
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
     #[test]
     fn f401() -> Result<()> {
         let mut actual = check_path(
@@ -366,6 +615,57 @@ mod tests {
 
         Ok(())
     }
+
+    #[test]
+    fn f404() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/F404.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::F404]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![Check {
+            kind: CheckKind::LateFutureImport,
+            location: Location::new(7, 1),
+            fix: None,
+        }];
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
+    #[test]
+    fn f407() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/F407.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::F407]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![Check {
+            kind: CheckKind::FutureFeatureNotDefined("non_existent_feature".to_string()),
+            location: Location::new(2, 1),
+            fix: None,
+        }];
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
     #[test]
     fn f541() -> Result<()> {
         let mut actual = check_path(
@@ -551,6 +851,90 @@ mod tests {
         Ok(())
     }
 
+    #[test]
+    fn f701() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/F701.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::F701]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![
+            Check {
+                kind: CheckKind::BreakOutsideLoop,
+                location: Location::new(4, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::BreakOutsideLoop,
+                location: Location::new(16, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::BreakOutsideLoop,
+                location: Location::new(20, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::BreakOutsideLoop,
+                location: Location::new(23, 1),
+                fix: None,
+            },
+        ];
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
+    #[test]
+    fn f702() -> Result<()> {
+        let mut actual = check_path(
+            Path::new("./resources/test/fixtures/F702.py"),
+            &settings::Settings {
+                line_length: 88,
+                exclude: vec![],
+                select: BTreeSet::from([CheckCode::F702]),
+            },
+            &fixer::Mode::Generate,
+        )?;
+        actual.sort_by_key(|check| check.location);
+        let expected = vec![
+            Check {
+                kind: CheckKind::ContinueOutsideLoop,
+                location: Location::new(4, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::ContinueOutsideLoop,
+                location: Location::new(16, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::ContinueOutsideLoop,
+                location: Location::new(20, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::ContinueOutsideLoop,
+                location: Location::new(23, 1),
+                fix: None,
+            },
+        ];
+        assert_eq!(actual.len(), expected.len());
+        for i in 0..actual.len() {
+            assert_eq!(actual[i], expected[i]);
+        }
+
+        Ok(())
+    }
+
     #[test]
     fn f704() -> Result<()> {
         let mut actual = check_path(
@@ -814,6 +1198,21 @@ mod tests {
                 location: Location::new(16, 5),
                 fix: None,
             },
+            Check {
+                kind: CheckKind::UnusedVariable("foo".to_string()),
+                location: Location::new(20, 5),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::UnusedVariable("a".to_string()),
+                location: Location::new(21, 6),
+                fix: None,
+            },
+            Check {
+                kind: CheckKind::UnusedVariable("b".to_string()),
+                location: Location::new(21, 9),
+                fix: None,
+            },
         ];
         assert_eq!(actual.len(), expected.len());
         for i in 0..actual.len() {

src/pyproject.rs

@@ -265,10 +265,16 @@ other-attribute = 1
                     CheckCode::E712,
                     CheckCode::E713,
                     CheckCode::E714,
+                    CheckCode::E722,
                     CheckCode::E731,
+                    CheckCode::E741,
+                    CheckCode::E742,
+                    CheckCode::E743,
                     CheckCode::E902,
                     CheckCode::F401,
                     CheckCode::F403,
+                    CheckCode::F404,
+                    CheckCode::F407,
                     CheckCode::F541,
                     CheckCode::F601,
                     CheckCode::F602,
@@ -276,6 +282,8 @@ other-attribute = 1
                     CheckCode::F622,
                     CheckCode::F631,
                     CheckCode::F634,
+                    CheckCode::F701,
+                    CheckCode::F702,
                     CheckCode::F704,
                     CheckCode::F706,
                     CheckCode::F707,

src/python.rs

@@ -1,2 +1,3 @@
 pub mod builtins;
+pub mod future;
 pub mod typing;

src/python/future.rs

@@ -0,0 +1,13 @@
+/// A copy of `__future__.all_feature_names`.
+pub const ALL_FEATURE_NAMES: &[&str] = &[
+    "nested_scopes",
+    "generators",
+    "division",
+    "absolute_import",
+    "with_statement",
+    "print_function",
+    "unicode_literals",
+    "barry_as_FLUFL",
+    "generator_stop",
+    "annotations",
+];

src/settings.rs

@@ -50,10 +50,15 @@ impl Settings {
                     CheckCode::E712,
                     CheckCode::E713,
                     CheckCode::E714,
+                    CheckCode::E722,
                     CheckCode::E731,
+                    CheckCode::E741,
+                    CheckCode::E742,
+                    CheckCode::E743,
                     CheckCode::E902,
                     CheckCode::F401,
                     CheckCode::F403,
+                    CheckCode::F407,
                     CheckCode::F541,
                     CheckCode::F601,
                     CheckCode::F602,
@@ -61,6 +66,8 @@ impl Settings {
                     CheckCode::F622,
                     CheckCode::F631,
                     CheckCode::F634,
+                    CheckCode::F701,
+                    CheckCode::F702,
                     CheckCode::F704,
                     CheckCode::F706,
                     CheckCode::F707,