Implement F407

README.md

@@ -124,7 +124,7 @@ 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 30 rules. (Note that these 30 rules likely cover a disproportionate share of errors:
+implements 31 rules. (Note that these 31 rules likely cover a disproportionate share of errors:
 unused imports, undefined variables, etc.)
 
 Of the unimplemented rules, ruff is missing:
@@ -158,6 +158,7 @@ Beyond rule-set parity, ruff suffers from the following limitations vis-à-vis F
 | 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 |

examples/generate_rules_table.rs

@@ -9,6 +9,7 @@ fn main() {
         CheckKind::DoNotAssignLambda,
         CheckKind::DuplicateArgumentName,
         CheckKind::FStringMissingPlaceholders,
+        CheckKind::FutureFeatureNotDefined("...".to_string()),
         CheckKind::IOError("...".to_string()),
         CheckKind::IfTuple,
         CheckKind::ImportStarUsage,

resources/test/fixtures/F407.py

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

resources/test/fixtures/pyproject.toml

@@ -14,6 +14,7 @@ select = [
     "F401",
     "F403",
     "F404",
+    "F407",
     "F541",
     "F601",
     "F602",

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;
 
@@ -391,7 +393,16 @@ where
                             },
                         );
 
-                        if !self.futures_allowed && self.settings.select.contains(&CheckCode::F404)
+                        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));

src/checks.rs

@@ -20,6 +20,7 @@ pub enum CheckCode {
     F401,
     F403,
     F404,
+    F407,
     F541,
     F601,
     F602,
@@ -57,6 +58,7 @@ impl FromStr for CheckCode {
             "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),
@@ -95,6 +97,7 @@ impl CheckCode {
             CheckCode::F401 => "F401",
             CheckCode::F403 => "F403",
             CheckCode::F404 => "F404",
+            CheckCode::F407 => "F407",
             CheckCode::F541 => "F541",
             CheckCode::F601 => "F601",
             CheckCode::F602 => "F602",
@@ -131,6 +134,7 @@ impl CheckCode {
             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,
@@ -174,6 +178,7 @@ pub enum CheckKind {
     DoNotAssignLambda,
     DuplicateArgumentName,
     FStringMissingPlaceholders,
+    FutureFeatureNotDefined(String),
     IOError(String),
     IfTuple,
     ImportStarUsage,
@@ -209,6 +214,7 @@ impl CheckKind {
             CheckKind::DefaultExceptNotLast => "DefaultExceptNotLast",
             CheckKind::DuplicateArgumentName => "DuplicateArgumentName",
             CheckKind::FStringMissingPlaceholders => "FStringMissingPlaceholders",
+            CheckKind::FutureFeatureNotDefined(_) => "FutureFeatureNotDefined",
             CheckKind::IOError(_) => "IOError",
             CheckKind::IfTuple => "IfTuple",
             CheckKind::ImportStarUsage => "ImportStarUsage",
@@ -246,6 +252,7 @@ impl CheckKind {
             CheckKind::DefaultExceptNotLast => &CheckCode::F707,
             CheckKind::DuplicateArgumentName => &CheckCode::F831,
             CheckKind::FStringMissingPlaceholders => &CheckCode::F541,
+            CheckKind::FutureFeatureNotDefined(_) => &CheckCode::F407,
             CheckKind::IOError(_) => &CheckCode::E902,
             CheckKind::IfTuple => &CheckCode::F634,
             CheckKind::ImportStarUsage => &CheckCode::F403,
@@ -290,6 +297,9 @@ impl CheckKind {
             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}`")
             }
@@ -384,6 +394,7 @@ impl CheckKind {
             CheckKind::DoNotAssignLambda => false,
             CheckKind::DuplicateArgumentName => false,
             CheckKind::FStringMissingPlaceholders => false,
+            CheckKind::FutureFeatureNotDefined(_) => false,
             CheckKind::IOError(_) => false,
             CheckKind::IfTuple => false,
             CheckKind::ImportStarUsage => false,

src/linter.rs

@@ -535,6 +535,31 @@ mod tests {
         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(

src/pyproject.rs

@@ -271,6 +271,7 @@ other-attribute = 1
                     CheckCode::F401,
                     CheckCode::F403,
                     CheckCode::F404,
+                    CheckCode::F407,
                     CheckCode::F541,
                     CheckCode::F601,
                     CheckCode::F602,

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

@@ -55,6 +55,7 @@ impl Settings {
                     CheckCode::E902,
                     CheckCode::F401,
                     CheckCode::F403,
+                    CheckCode::F407,
                     CheckCode::F541,
                     CheckCode::F601,
                     CheckCode::F602,