Automatically remove unused imports (#298)

resources/test/fixtures/F401.py

@@ -30,6 +30,17 @@ if TYPE_CHECKING:
     from models import Fruit, Nut, Vegetable
 
 
+if TYPE_CHECKING:
+    import shelve
+    import importlib
+
+if TYPE_CHECKING:
+    """Hello, world!"""
+    import pathlib
+
+    z = 1
+
+
 class X:
     datetime: datetime
     foo: Type["NamedTuple"]
@@ -39,6 +50,9 @@ class X:
         y = Counter()
         z = multiprocessing.pool.ThreadPool()
 
+    def b(self) -> None:
+        import pickle
+
 
 __all__ = ["ClassA"] + ["ClassB"]
 __all__ += ["ClassC"]

resources/test/fixtures/future_annotations.py

@@ -2,7 +2,10 @@ from __future__ import annotations
 
 from dataclasses import dataclass
 
-from models import Fruit, Nut
+from models import (
+    Fruit,
+    Nut,
+)
 
 
 @dataclass

src/ast/checks.rs

@@ -99,7 +99,7 @@ pub fn check_unused_variables(
         {
             checks.push(Check::new(
                 CheckKind::UnusedVariable(name.to_string()),
-                locator.locate_check(binding.location),
+                locator.locate_check(binding.range),
             ));
         }
     }

src/ast/operations.rs

@@ -1,6 +1,6 @@
 use rustpython_parser::ast::{Constant, Expr, ExprKind, Location, Stmt, StmtKind};
 
-use crate::ast::types::{BindingKind, Scope};
+use crate::ast::types::{BindingKind, Range, Scope};
 
 /// Extract the names bound to a given __all__ assignment.
 pub fn extract_all_names(stmt: &Stmt, scope: &Scope) -> Vec<String> {
@@ -148,7 +148,7 @@ impl<'a> SourceCodeLocator<'a> {
         &self.content[offset..]
     }
 
-    pub fn slice_source_code_range(&mut self, start: &Location, end: &Location) -> &'a str {
+    pub fn slice_source_code_range(&mut self, range: &Range) -> &'a str {
         if !self.initialized {
             let mut offset = 0;
             for i in self.content.lines() {
@@ -158,8 +158,8 @@ impl<'a> SourceCodeLocator<'a> {
             }
             self.initialized = true;
         }
-        let start = self.offsets[start.row() - 1] + start.column() - 1;
+        let start = self.offsets[range.location.row() - 1] + range.location.column() - 1;
-        let end = self.offsets[end.row() - 1] + end.column() - 1;
+        let end = self.offsets[range.end_location.row() - 1] + range.end_location.column() - 1;
         &self.content[start..end]
     }
 }

src/ast/types.rs

@@ -8,7 +8,7 @@ fn id() -> usize {
     COUNTER.fetch_add(1, Ordering::Relaxed)
 }
 
-#[derive(Clone, Copy, Debug, Default)]
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, PartialOrd, Ord)]
 pub struct Range {
     pub location: Location,
     pub end_location: Location,
@@ -55,6 +55,12 @@ impl Scope {
     }
 }
 
+#[derive(Clone, Debug)]
+pub struct BindingContext {
+    pub defined_by: usize,
+    pub defined_in: Option<usize>,
+}
+
 #[derive(Clone, Debug)]
 pub enum BindingKind {
     Annotation,
@@ -67,15 +73,16 @@ pub enum BindingKind {
     Definition,
     Export(Vec<String>),
     FutureImportation,
-    Importation(String),
     StarImportation,
-    SubmoduleImportation(String),
+    Importation(String, BindingContext),
+    FromImportation(String, BindingContext),
+    SubmoduleImportation(String, BindingContext),
 }
 
 #[derive(Clone, Debug)]
 pub struct Binding {
     pub kind: BindingKind,
-    pub location: Range,
+    pub range: Range,
     /// Tuple of (scope index, range) indicating the scope and range at which the binding was
     /// last used.
     pub used: Option<(usize, Range)>,
@@ -84,3 +91,9 @@ pub struct Binding {
 pub trait CheckLocator {
     fn locate_check(&self, default: Range) -> Range;
 }
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
+pub enum ImportKind {
+    Import,
+    ImportFrom,
+}

src/autofix/fixer.rs

@@ -2,6 +2,7 @@ use std::fs;
 use std::path::Path;
 
 use anyhow::Result;
+use itertools::Itertools;
 use rustpython_parser::ast::Location;
 
 use crate::checks::{Check, Fix};
@@ -43,7 +44,7 @@ fn apply_fixes<'a>(fixes: impl Iterator<Item = &'a mut Fix>, contents: &str) ->
     let mut output = "".to_string();
     let mut last_pos: Location = Location::new(0, 0);
 
-    for fix in fixes {
+    for fix in fixes.sorted_by_key(|fix| fix.location) {
         // Best-effort approach: if this fix overlaps with a fix we've already applied, skip it.
         if last_pos > fix.location {
             continue;
@@ -71,14 +72,19 @@ fn apply_fixes<'a>(fixes: impl Iterator<Item = &'a mut Fix>, contents: &str) ->
         fix.applied = true;
     }
 
-    if last_pos.row() > 0 || last_pos.column() > 0 {
+    if last_pos.row() > 0
+        && (last_pos.row() - 1) < lines.len()
+        && (last_pos.row() > 0 || last_pos.column() > 0)
+    {
         output.push_str(&lines[last_pos.row() - 1][last_pos.column() - 1..]);
         output.push('\n');
     }
+    if last_pos.row() < lines.len() {
         for line in &lines[last_pos.row()..] {
             output.push_str(line);
             output.push('\n');
         }
+    }
 
     output
 }

src/autofix/fixes.rs

@@ -1,9 +1,14 @@
+use anyhow::Result;
+use itertools::Itertools;
+use libcst_native::ImportNames::Aliases;
+use libcst_native::NameOrAttribute::N;
 use libcst_native::{Codegen, Expression, SmallStatement, Statement};
-use rustpython_parser::ast::{Expr, Keyword, Location};
+use rustpython_parser::ast::{ExcepthandlerKind, Expr, Keyword, Location, Stmt, StmtKind};
 use rustpython_parser::lexer;
 use rustpython_parser::token::Tok;
 
 use crate::ast::operations::SourceCodeLocator;
+use crate::ast::types::Range;
 use crate::checks::Fix;
 
 /// Convert a location within a file (relative to `base`) to an absolute position.
@@ -127,7 +132,8 @@ pub fn remove_class_def_base(
 }
 
 pub fn remove_super_arguments(locator: &mut SourceCodeLocator, expr: &Expr) -> Option<Fix> {
-    let contents = locator.slice_source_code_range(&expr.location, &expr.end_location);
+    let range = Range::from_located(expr);
+    let contents = locator.slice_source_code_range(&range);
 
     let mut tree = match libcst_native::parse_module(contents, None) {
         Ok(m) => m,
@@ -146,8 +152,8 @@ pub fn remove_super_arguments(locator: &mut SourceCodeLocator, expr: &Expr) -> O
 
                 return Some(Fix {
                     content: state.to_string(),
-                    location: expr.location,
+                    location: range.location,
-                    end_location: expr.end_location,
+                    end_location: range.end_location,
                     applied: false,
                 });
             }
@@ -156,3 +162,170 @@ pub fn remove_super_arguments(locator: &mut SourceCodeLocator, expr: &Expr) -> O
 
     None
 }
+
+/// Determine if a body contains only a single statement, taking into account deleted.
+fn has_single_child(body: &[Stmt], deleted: &[&Stmt]) -> bool {
+    body.iter().filter(|child| !deleted.contains(child)).count() == 1
+}
+
+/// Determine if a child is the only statement in its body.
+fn is_lone_child(child: &Stmt, parent: &Stmt, deleted: &[&Stmt]) -> Result<bool> {
+    match &parent.node {
+        StmtKind::FunctionDef { body, .. }
+        | StmtKind::AsyncFunctionDef { body, .. }
+        | StmtKind::ClassDef { body, .. }
+        | StmtKind::With { body, .. }
+        | StmtKind::AsyncWith { body, .. } => {
+            if body.iter().contains(child) {
+                Ok(has_single_child(body, deleted))
+            } else {
+                Err(anyhow::anyhow!("Unable to find child in parent body."))
+            }
+        }
+        StmtKind::For { body, orelse, .. }
+        | StmtKind::AsyncFor { body, orelse, .. }
+        | StmtKind::While { body, orelse, .. }
+        | StmtKind::If { body, orelse, .. } => {
+            if body.iter().contains(child) {
+                Ok(has_single_child(body, deleted))
+            } else if orelse.iter().contains(child) {
+                Ok(has_single_child(orelse, deleted))
+            } else {
+                Err(anyhow::anyhow!("Unable to find child in parent body."))
+            }
+        }
+        StmtKind::Try {
+            body,
+            handlers,
+            orelse,
+            finalbody,
+        } => {
+            if body.iter().contains(child) {
+                Ok(has_single_child(body, deleted))
+            } else if orelse.iter().contains(child) {
+                Ok(has_single_child(orelse, deleted))
+            } else if finalbody.iter().contains(child) {
+                Ok(has_single_child(finalbody, deleted))
+            } else if let Some(body) = handlers.iter().find_map(|handler| match &handler.node {
+                ExcepthandlerKind::ExceptHandler { body, .. } => {
+                    if body.iter().contains(child) {
+                        Some(body)
+                    } else {
+                        None
+                    }
+                }
+            }) {
+                Ok(has_single_child(body, deleted))
+            } else {
+                Err(anyhow::anyhow!("Unable to find child in parent body."))
+            }
+        }
+        _ => Err(anyhow::anyhow!("Unable to find child in parent body.")),
+    }
+}
+
+fn remove_stmt(stmt: &Stmt, parent: Option<&Stmt>, deleted: &[&Stmt]) -> Result<Fix> {
+    if parent
+        .map(|parent| is_lone_child(stmt, parent, deleted))
+        .map_or(Ok(None), |v| v.map(Some))?
+        .unwrap_or_default()
+    {
+        // If removing this node would lead to an invalid syntax tree, replace
+        // it with a `pass`.
+        Ok(Fix {
+            location: stmt.location,
+            end_location: stmt.end_location,
+            content: "pass".to_string(),
+            applied: false,
+        })
+    } else {
+        // Otherwise, nuke the entire line.
+        // TODO(charlie): This logic assumes that there are no multi-statement physical lines.
+        Ok(Fix {
+            location: Location::new(stmt.location.row(), 1),
+            end_location: Location::new(stmt.end_location.row() + 1, 1),
+            content: "".to_string(),
+            applied: false,
+        })
+    }
+}
+
+/// Generate a Fix to remove any unused imports from an `import` statement.
+pub fn remove_unused_imports(stmt: &Stmt, parent: Option<&Stmt>, deleted: &[&Stmt]) -> Result<Fix> {
+    remove_stmt(stmt, parent, deleted)
+}
+
+/// Generate a Fix to remove any unused imports from an `import from` statement.
+pub fn remove_unused_import_froms(
+    locator: &mut SourceCodeLocator,
+    full_names: &[String],
+    stmt: &Stmt,
+    parent: Option<&Stmt>,
+    deleted: &[&Stmt],
+) -> Result<Fix> {
+    let mut tree = match libcst_native::parse_module(
+        locator.slice_source_code_range(&Range::from_located(stmt)),
+        None,
+    ) {
+        Ok(m) => m,
+        Err(_) => return Err(anyhow::anyhow!("Failed to extract CST from source.")),
+    };
+
+    let body = if let Some(Statement::Simple(body)) = tree.body.first_mut() {
+        body
+    } else {
+        return Err(anyhow::anyhow!("Expected node to be: Statement::Simple."));
+    };
+    let body = if let Some(SmallStatement::ImportFrom(body)) = body.body.first_mut() {
+        body
+    } else {
+        return Err(anyhow::anyhow!(
+            "Expected node to be: SmallStatement::ImportFrom."
+        ));
+    };
+    let aliases = if let Aliases(aliases) = &mut body.names {
+        aliases
+    } else {
+        return Err(anyhow::anyhow!("Expected node to be: Aliases."));
+    };
+
+    // Preserve the trailing comma (or not) from the last entry.
+    let trailing_comma = aliases.last().and_then(|alias| alias.comma.clone());
+
+    // Identify unused imports from within the `import from`.
+    let mut removable = vec![];
+    for (index, alias) in aliases.iter().enumerate() {
+        if let N(name) = &alias.name {
+            let import_name = if let Some(N(module_name)) = &body.module {
+                format!("{}.{}", module_name.value, name.value)
+            } else {
+                name.value.to_string()
+            };
+            if full_names.contains(&import_name) {
+                removable.push(index);
+            }
+        }
+    }
+    // TODO(charlie): This is quadratic.
+    for index in removable.iter().rev() {
+        aliases.remove(*index);
+    }
+
+    if let Some(alias) = aliases.last_mut() {
+        alias.comma = trailing_comma;
+    }
+
+    if aliases.is_empty() {
+        remove_stmt(stmt, parent, deleted)
+    } else {
+        let mut state = Default::default();
+        tree.codegen(&mut state);
+
+        Ok(Fix {
+            content: state.to_string(),
+            location: stmt.location,
+            end_location: stmt.end_location,
+            applied: false,
+        })
+    }
+}

src/check_ast.rs

@@ -1,6 +1,8 @@
+use std::collections::{BTreeMap, BTreeSet};
 use std::ops::Deref;
 use std::path::Path;
 
+use log::error;
 use once_cell::sync::Lazy;
 use regex::Regex;
 use rustpython_parser::ast::{
@@ -12,11 +14,12 @@ use rustpython_parser::parser;
 use crate::ast::operations::{extract_all_names, SourceCodeLocator};
 use crate::ast::relocate::relocate_expr;
 use crate::ast::types::{
-    Binding, BindingKind, CheckLocator, FunctionScope, Range, Scope, ScopeKind,
+    Binding, BindingContext, BindingKind, CheckLocator, FunctionScope, ImportKind, Range, Scope,
+    ScopeKind,
 };
 use crate::ast::visitor::{walk_excepthandler, Visitor};
 use crate::ast::{checks, operations, visitor};
-use crate::autofix::fixer;
+use crate::autofix::{fixer, fixes};
 use crate::checks::{Check, CheckCode, CheckKind};
 use crate::python::builtins::{BUILTINS, MAGIC_GLOBALS};
 use crate::python::future::ALL_FEATURE_NAMES;
@@ -55,6 +58,8 @@ struct Checker<'a> {
     seen_docstring: bool,
     futures_allowed: bool,
     annotations_future_enabled: bool,
+    // Edit tracking.
+    deletions: BTreeSet<usize>,
 }
 
 impl<'a> Checker<'a> {
@@ -87,6 +92,7 @@ impl<'a> Checker<'a> {
             seen_docstring: false,
             futures_allowed: true,
             annotations_future_enabled: false,
+            deletions: Default::default(),
         }
     }
 }
@@ -221,7 +227,7 @@ where
                                 Binding {
                                     kind: BindingKind::Assignment,
                                     used: Some((global_scope_id, Range::from_located(stmt))),
-                                    location: Range::from_located(stmt),
+                                    range: Range::from_located(stmt),
                                 },
                             );
                         }
@@ -329,7 +335,7 @@ where
                     Binding {
                         kind: BindingKind::Definition,
                         used: None,
-                        location: Range::from_located(stmt),
+                        range: Range::from_located(stmt),
                     },
                 );
             }
@@ -424,9 +430,10 @@ where
                             Binding {
                                 kind: BindingKind::SubmoduleImportation(
                                     alias.node.name.to_string(),
+                                    self.binding_context(),
                                 ),
                                 used: None,
-                                location: Range::from_located(stmt),
+                                range: Range::from_located(stmt),
                             },
                         )
                     } else {
@@ -447,9 +454,10 @@ where
                                         .asname
                                         .clone()
                                         .unwrap_or_else(|| alias.node.name.clone()),
+                                    self.binding_context(),
                                 ),
                                 used: None,
-                                location: Range::from_located(stmt),
+                                range: Range::from_located(stmt),
                             },
                         )
                     }
@@ -492,7 +500,7 @@ where
                                     .id,
                                     Range::from_located(stmt),
                                 )),
-                                location: Range::from_located(stmt),
+                                range: Range::from_located(stmt),
                             },
                         );
 
@@ -528,7 +536,7 @@ where
                             Binding {
                                 kind: BindingKind::StarImportation,
                                 used: None,
-                                location: Range::from_located(stmt),
+                                range: Range::from_located(stmt),
                             },
                         );
 
@@ -561,12 +569,15 @@ where
                         }
 
                         let binding = Binding {
-                            kind: BindingKind::Importation(match module {
+                            kind: BindingKind::FromImportation(
+                                match module {
                                     None => name.clone(),
                                     Some(parent) => format!("{}.{}", parent, name),
-                            }),
+                                },
+                                self.binding_context(),
+                            ),
                             used: None,
-                            location: Range::from_located(stmt),
+                            range: Range::from_located(stmt),
                         };
                         self.add_binding(name, binding)
                     }
@@ -661,7 +672,7 @@ where
                 Binding {
                     kind: BindingKind::ClassDefinition,
                     used: None,
-                    location: Range::from_located(stmt),
+                    range: Range::from_located(stmt),
                 },
             );
         };
@@ -1106,7 +1117,6 @@ where
                                 ),
                                 parent,
                             );
-                            self.parents.push(parent);
                         }
 
                         let parent =
@@ -1125,7 +1135,6 @@ where
                             ),
                             parent,
                         );
-                        self.parents.push(parent);
 
                         walk_excepthandler(self, excepthandler);
 
@@ -1183,7 +1192,7 @@ where
             Binding {
                 kind: BindingKind::Argument,
                 used: None,
-                location: Range::from_located(arg),
+                range: Range::from_located(arg),
             },
         );
 
@@ -1239,7 +1248,7 @@ impl<'a> Checker<'a> {
                 (*builtin).to_string(),
                 Binding {
                     kind: BindingKind::Builtin,
-                    location: Default::default(),
+                    range: Default::default(),
                     used: None,
                 },
             );
@@ -1249,13 +1258,23 @@ impl<'a> Checker<'a> {
                 (*builtin).to_string(),
                 Binding {
                     kind: BindingKind::Builtin,
-                    location: Default::default(),
+                    range: Default::default(),
                     used: None,
                 },
             );
         }
     }
 
+    fn binding_context(&self) -> BindingContext {
+        let mut rev = self.parent_stack.iter().rev().fuse();
+        let defined_by = *rev.next().expect("Expected to bind within a statement.");
+        let defined_in = rev.next().cloned();
+        BindingContext {
+            defined_by,
+            defined_in,
+        }
+    }
+
     fn add_binding(&mut self, name: String, binding: Binding) {
         let scope = &mut self.scopes[*(self.scope_stack.last().expect("No current scope found."))];
 
@@ -1264,20 +1283,23 @@ impl<'a> Checker<'a> {
             None => binding,
             Some(existing) => {
                 if self.settings.select.contains(&CheckCode::F402)
-                    && matches!(existing.kind, BindingKind::Importation(_))
                     && matches!(binding.kind, BindingKind::LoopVar)
+                    && matches!(
+                        existing.kind,
+                        BindingKind::Importation(_, _) | BindingKind::FromImportation(_, _)
+                    )
                 {
                     self.checks.push(Check::new(
                         CheckKind::ImportShadowedByLoopVar(
                             name.clone(),
-                            existing.location.location.row(),
+                            existing.range.location.row(),
                         ),
-                        binding.location,
+                        binding.range,
                     ));
                 }
                 Binding {
                     kind: binding.kind,
-                    location: binding.location,
+                    range: binding.range,
                     used: existing.used,
                 }
             }
@@ -1378,7 +1400,7 @@ impl<'a> Checker<'a> {
                     Binding {
                         kind: BindingKind::Annotation,
                         used: None,
-                        location: Range::from_located(expr),
+                        range: Range::from_located(expr),
                     },
                 );
                 return;
@@ -1394,7 +1416,7 @@ impl<'a> Checker<'a> {
                     Binding {
                         kind: BindingKind::LoopVar,
                         used: None,
-                        location: Range::from_located(expr),
+                        range: Range::from_located(expr),
                     },
                 );
                 return;
@@ -1406,7 +1428,7 @@ impl<'a> Checker<'a> {
                     Binding {
                         kind: BindingKind::Binding,
                         used: None,
-                        location: Range::from_located(expr),
+                        range: Range::from_located(expr),
                     },
                 );
                 return;
@@ -1426,7 +1448,7 @@ impl<'a> Checker<'a> {
                     Binding {
                         kind: BindingKind::Export(extract_all_names(parent, current)),
                         used: None,
-                        location: Range::from_located(expr),
+                        range: Range::from_located(expr),
                     },
                 );
                 return;
@@ -1437,7 +1459,7 @@ impl<'a> Checker<'a> {
                 Binding {
                     kind: BindingKind::Assignment,
                     used: None,
-                    location: Range::from_located(expr),
+                    range: Range::from_located(expr),
                 },
             );
         }
@@ -1571,7 +1593,7 @@ impl<'a> Checker<'a> {
                             if !scope.values.contains_key(name) {
                                 self.checks.push(Check::new(
                                     CheckKind::UndefinedExport(name.to_string()),
-                                    self.locate_check(all_binding.location),
+                                    self.locate_check(all_binding.range),
                                 ));
                             }
                         }
@@ -1594,7 +1616,7 @@ impl<'a> Checker<'a> {
                             if !scope.values.contains_key(name) {
                                 self.checks.push(Check::new(
                                     CheckKind::ImportStarUsage(name.clone(), from_list.join(", ")),
-                                    self.locate_check(all_binding.location),
+                                    self.locate_check(all_binding.range),
                                 ));
                             }
                         }
@@ -1603,6 +1625,11 @@ impl<'a> Checker<'a> {
             }
 
             if self.settings.select.contains(&CheckCode::F401) {
+                // Collect all unused imports by location. (Multiple unused imports at the same
+                // location indicates an `import from`.)
+                let mut unused: BTreeMap<(ImportKind, usize, Option<usize>), Vec<String>> =
+                    BTreeMap::new();
+
                 for (name, binding) in scope.values.iter().rev() {
                     let used = binding.used.is_some()
                         || all_names
@@ -1611,17 +1638,82 @@ impl<'a> Checker<'a> {
 
                     if !used {
                         match &binding.kind {
-                            BindingKind::Importation(full_name)
+                            BindingKind::FromImportation(full_name, context) => {
-                            | BindingKind::SubmoduleImportation(full_name) => {
+                                let full_names = unused
-                                self.checks.push(Check::new(
+                                    .entry((
-                                    CheckKind::UnusedImport(full_name.to_string()),
+                                        ImportKind::ImportFrom,
-                                    self.locate_check(binding.location),
+                                        context.defined_by,
-                                ));
+                                        context.defined_in,
+                                    ))
+                                    .or_insert(vec![]);
+                                full_names.push(full_name.to_string());
+                            }
+                            BindingKind::Importation(full_name, context)
+                            | BindingKind::SubmoduleImportation(full_name, context) => {
+                                let full_names = unused
+                                    .entry((
+                                        ImportKind::Import,
+                                        context.defined_by,
+                                        context.defined_in,
+                                    ))
+                                    .or_insert(vec![]);
+                                full_names.push(full_name.to_string());
                             }
                             _ => {}
                         }
                     }
                 }
+
+                for ((kind, defined_by, defined_in), full_names) in unused {
+                    let child = self.parents[defined_by];
+                    let parent = defined_in.map(|defined_in| self.parents[defined_in]);
+
+                    let mut check = Check::new(
+                        CheckKind::UnusedImport(full_names.join(", ")),
+                        self.locate_check(Range::from_located(child)),
+                    );
+
+                    if matches!(self.autofix, fixer::Mode::Generate | fixer::Mode::Apply) {
+                        let deleted: Vec<&Stmt> = self
+                            .deletions
+                            .iter()
+                            .map(|index| self.parents[*index])
+                            .collect();
+
+                        match kind {
+                            ImportKind::Import => {
+                                match fixes::remove_unused_imports(child, parent, &deleted) {
+                                    Ok(fix) => {
+                                        if fix.content.is_empty() || fix.content == "pass" {
+                                            self.deletions.insert(defined_by);
+                                        }
+                                        check.amend(fix)
+                                    }
+                                    Err(e) => error!("Failed to fix unused imports: {}", e),
+                                }
+                            }
+                            ImportKind::ImportFrom => {
+                                match fixes::remove_unused_import_froms(
+                                    &mut self.locator,
+                                    &full_names,
+                                    child,
+                                    parent,
+                                    &deleted,
+                                ) {
+                                    Ok(fix) => {
+                                        if fix.content.is_empty() || fix.content == "pass" {
+                                            self.deletions.insert(defined_by);
+                                        }
+                                        check.amend(fix)
+                                    }
+                                    Err(e) => error!("Failed to fix unused imports: {}", e),
+                                }
+                            }
+                        }
+                    }
+
+                    self.checks.push(check);
+                }
             }
         }
     }
@@ -1666,12 +1758,12 @@ impl<'a> Checker<'a> {
 
 pub fn check_ast(
     python_ast: &Suite,
-    content: &str,
+    contents: &str,
     settings: &Settings,
     autofix: &fixer::Mode,
     path: &Path,
 ) -> Vec<Check> {
-    let mut checker = Checker::new(settings, autofix, path, content);
+    let mut checker = Checker::new(settings, autofix, path, contents);
     checker.push_scope(Scope::new(ScopeKind::Module));
     checker.bind_builtins();
 

src/checks.rs

@@ -713,6 +713,7 @@ impl CheckKind {
                 | CheckKind::UselessObjectInheritance(_)
                 | CheckKind::UnusedNOQA(_)
                 | CheckKind::SuperCallWithParameters
+                | CheckKind::UnusedImport(_)
         )
     }
 }

src/snapshots/ruff__linter__tests__f401.snap

@@ -10,7 +10,15 @@ expression: checks
   end_location:
     row: 3
     column: 17
-  fix: ~
+  fix:
+    content: ""
+    location:
+      row: 3
+      column: 1
+    end_location:
+      row: 4
+      column: 1
+    applied: false
 - kind:
     UnusedImport: collections.OrderedDict
   location:
@@ -19,7 +27,15 @@ expression: checks
   end_location:
     row: 9
     column: 2
-  fix: ~
+  fix:
+    content: "from collections import (\n    Counter,\n    namedtuple,\n)"
+    location:
+      row: 5
+      column: 1
+    end_location:
+      row: 9
+      column: 2
+    applied: false
 - kind:
     UnusedImport: logging.handlers
   location:
@@ -28,5 +44,81 @@ expression: checks
   end_location:
     row: 13
     column: 24
-  fix: ~
+  fix:
+    content: ""
+    location:
+      row: 13
+      column: 1
+    end_location:
+      row: 14
+      column: 1
+    applied: false
+- kind:
+    UnusedImport: shelve
+  location:
+    row: 34
+    column: 5
+  end_location:
+    row: 34
+    column: 18
+  fix:
+    content: ""
+    location:
+      row: 34
+      column: 1
+    end_location:
+      row: 35
+      column: 1
+    applied: false
+- kind:
+    UnusedImport: importlib
+  location:
+    row: 35
+    column: 5
+  end_location:
+    row: 35
+    column: 21
+  fix:
+    content: pass
+    location:
+      row: 35
+      column: 5
+    end_location:
+      row: 35
+      column: 21
+    applied: false
+- kind:
+    UnusedImport: pathlib
+  location:
+    row: 39
+    column: 5
+  end_location:
+    row: 39
+    column: 19
+  fix:
+    content: ""
+    location:
+      row: 39
+      column: 1
+    end_location:
+      row: 40
+      column: 1
+    applied: false
+- kind:
+    UnusedImport: pickle
+  location:
+    row: 54
+    column: 9
+  end_location:
+    row: 54
+    column: 22
+  fix:
+    content: pass
+    location:
+      row: 54
+      column: 9
+    end_location:
+      row: 54
+      column: 22
+    applied: false
 

src/snapshots/ruff__linter__tests__future_annotations.snap

@@ -8,16 +8,24 @@ expression: checks
     row: 5
     column: 1
   end_location:
+    row: 8
+    column: 2
+  fix:
+    content: "from models import (\n    Fruit,\n)"
+    location:
       row: 5
-    column: 30
+      column: 1
-  fix: ~
+    end_location:
+      row: 8
+      column: 2
+    applied: false
 - kind:
     UndefinedName: Bar
   location:
-    row: 22
+    row: 25
     column: 19
   end_location:
-    row: 22
+    row: 25
     column: 22
   fix: ~