Implement nested with detection (SIM117) (#1651)

README.md

@@ -965,7 +965,8 @@ For more, see [flake8-simplify](https://pypi.org/project/flake8-simplify/0.19.3/
 
 | Code | Name | Message | Fix |
 | ---- | ---- | ------- | --- |
-| SIM102 | NestedIfStatements | Use a single if-statement instead of nested if-statements |  |
+| SIM117 | MultipleWithStatements | Use a single `with` statement with multiple contexts instead of nested `with` statements |  |
+| SIM102 | NestedIfStatements | Use a single `if` statement instead of nested `if` statements |  |
 | SIM105 | UseContextlibSuppress | Use `contextlib.suppress(...)` instead of try-except-pass |  |
 | SIM118 | KeyInDict | Use `key in dict` instead of `key in dict.keys()` | 🛠 |
 | SIM220 | AAndNotA | Use `False` instead of `... and not ...` | 🛠 |

resources/test/fixtures/flake8_simplify/SIM117.py

@@ -0,0 +1,13 @@
+with A() as a:  # SIM117
+    with B() as b:
+        print("hello")
+
+with A() as a:
+    a()
+    with B() as b:
+        print("hello")
+
+with A() as a:
+    with B() as b:
+        print("hello")
+    a()

src/checkers/ast.rs

@@ -1216,6 +1216,9 @@ where
                 if self.settings.enabled.contains(&CheckCode::PT012) {
                     flake8_pytest_style::plugins::complex_raises(self, stmt, items, body);
                 }
+                if self.settings.enabled.contains(&CheckCode::SIM117) {
+                    flake8_simplify::plugins::multiple_with_statements(self, stmt);
+                }
             }
             StmtKind::While { body, orelse, .. } => {
                 if self.settings.enabled.contains(&CheckCode::B023) {

src/flake8_simplify/mod.rs

@@ -12,14 +12,15 @@ mod tests {
     use crate::registry::CheckCode;
     use crate::settings;
 
+    #[test_case(CheckCode::SIM102, Path::new("SIM102.py"); "SIM102")]
     #[test_case(CheckCode::SIM105, Path::new("SIM105.py"); "SIM105")]
+    #[test_case(CheckCode::SIM117, Path::new("SIM117.py"); "SIM117")]
     #[test_case(CheckCode::SIM118, Path::new("SIM118.py"); "SIM118")]
+    #[test_case(CheckCode::SIM220, Path::new("SIM220.py"); "SIM220")]
+    #[test_case(CheckCode::SIM221, Path::new("SIM221.py"); "SIM221")]
     #[test_case(CheckCode::SIM222, Path::new("SIM222.py"); "SIM222")]
     #[test_case(CheckCode::SIM223, Path::new("SIM223.py"); "SIM223")]
     #[test_case(CheckCode::SIM300, Path::new("SIM300.py"); "SIM300")]
-    #[test_case(CheckCode::SIM221, Path::new("SIM221.py"); "SIM221")]
-    #[test_case(CheckCode::SIM220, Path::new("SIM220.py"); "SIM220")]
-    #[test_case(CheckCode::SIM102, Path::new("SIM102.py"); "SIM102")]
     fn checks(check_code: CheckCode, path: &Path) -> Result<()> {
         let snapshot = format!("{}_{}", check_code.as_ref(), path.to_string_lossy());
         let checks = test_path(

src/flake8_simplify/plugins/ast_with.rs

@@ -0,0 +1,21 @@
+use rustpython_ast::{Stmt, StmtKind};
+
+use crate::ast::types::Range;
+use crate::checkers::ast::Checker;
+use crate::registry::{Check, CheckKind};
+
+/// SIM117
+pub fn multiple_with_statements(checker: &mut Checker, stmt: &Stmt) {
+    let StmtKind::With { body, .. } = &stmt.node else {
+        return;
+    };
+    if body.len() != 1 {
+        return;
+    }
+    if matches!(body[0].node, StmtKind::With { .. }) {
+        checker.add_check(Check::new(
+            CheckKind::MultipleWithStatements,
+            Range::from_located(stmt),
+        ));
+    }
+}

src/flake8_simplify/plugins/mod.rs

@@ -1,11 +1,12 @@
 pub use ast_bool_op::{a_and_not_a, a_or_not_a, and_false, or_true};
 pub use ast_if::nested_if_statements;
+pub use ast_with::multiple_with_statements;
 pub use key_in_dict::{key_in_dict_compare, key_in_dict_for};
 pub use use_contextlib_suppress::use_contextlib_suppress;
 pub use yoda_conditions::yoda_conditions;
-
 mod ast_bool_op;
 mod ast_if;
+mod ast_with;
 mod key_in_dict;
 mod use_contextlib_suppress;
 mod yoda_conditions;

src/flake8_simplify/snapshots/ruff__flake8_simplify__tests__SIM117_SIM117.py.snap

@@ -0,0 +1,14 @@
+---
+source: src/flake8_simplify/mod.rs
+expression: checks
+---
+- kind: MultipleWithStatements
+  location:
+    row: 1
+    column: 0
+  end_location:
+    row: 3
+    column: 22
+  fix: ~
+  parent: ~
+

src/registry.rs

@@ -217,6 +217,7 @@ pub enum CheckCode {
     YTT302,
     YTT303,
     // flake8-simplify
+    SIM117,
     SIM102,
     SIM105,
     SIM118,
@@ -953,6 +954,7 @@ pub enum CheckKind {
     SysVersionCmpStr10,
     SysVersionSlice1Referenced,
     // flake8-simplify
+    MultipleWithStatements,
     NestedIfStatements,
     AAndNotA(String),
     AOrNotA(String),
@@ -1389,6 +1391,7 @@ impl CheckCode {
             // flake8-simplify
             CheckCode::SIM102 => CheckKind::NestedIfStatements,
             CheckCode::SIM105 => CheckKind::UseContextlibSuppress("...".to_string()),
+            CheckCode::SIM117 => CheckKind::MultipleWithStatements,
             CheckCode::SIM118 => CheckKind::KeyInDict("key".to_string(), "dict".to_string()),
             CheckCode::SIM220 => CheckKind::AAndNotA("...".to_string()),
             CheckCode::SIM221 => CheckKind::AOrNotA("...".to_string()),
@@ -1923,6 +1926,7 @@ impl CheckCode {
             // flake8-simplify
             CheckCode::SIM102 => CheckCategory::Flake8Simplify,
             CheckCode::SIM105 => CheckCategory::Flake8Simplify,
+            CheckCode::SIM117 => CheckCategory::Flake8Simplify,
             CheckCode::SIM118 => CheckCategory::Flake8Simplify,
             CheckCode::SIM220 => CheckCategory::Flake8Simplify,
             CheckCode::SIM221 => CheckCategory::Flake8Simplify,
@@ -2175,13 +2179,14 @@ impl CheckKind {
             CheckKind::SysVersionCmpStr10 => &CheckCode::YTT302,
             CheckKind::SysVersionSlice1Referenced => &CheckCode::YTT303,
             // flake8-simplify
-            CheckKind::NestedIfStatements => &CheckCode::SIM102,
-            CheckKind::UseContextlibSuppress(..) => &CheckCode::SIM105,
-            CheckKind::KeyInDict(..) => &CheckCode::SIM118,
             CheckKind::AAndNotA(..) => &CheckCode::SIM220,
             CheckKind::AOrNotA(..) => &CheckCode::SIM221,
-            CheckKind::OrTrue => &CheckCode::SIM222,
             CheckKind::AndFalse => &CheckCode::SIM223,
+            CheckKind::KeyInDict(..) => &CheckCode::SIM118,
+            CheckKind::MultipleWithStatements => &CheckCode::SIM117,
+            CheckKind::NestedIfStatements => &CheckCode::SIM102,
+            CheckKind::OrTrue => &CheckCode::SIM222,
+            CheckKind::UseContextlibSuppress(..) => &CheckCode::SIM105,
             CheckKind::YodaConditions(..) => &CheckCode::SIM300,
             // pyupgrade
             CheckKind::ConvertNamedTupleFunctionalToClass(..) => &CheckCode::UP014,
@@ -2940,16 +2945,18 @@ impl CheckKind {
                 "`sys.version[:1]` referenced (python10), use `sys.version_info`".to_string()
             }
             // flake8-simplify
-            CheckKind::NestedIfStatements => {
-                "Use a single if-statement instead of nested if-statements".to_string()
-            }
+            CheckKind::AAndNotA(name) => format!("Use `False` instead of `{name} and not {name}`"),
+            CheckKind::AOrNotA(name) => format!("Use `True` instead of `{name} or not {name}`"),
+            CheckKind::AndFalse => "Use `False` instead of `... and False`".to_string(),
             CheckKind::KeyInDict(key, dict) => {
                 format!("Use `{key} in {dict}` instead of `{key} in {dict}.keys()`")
             }
-            CheckKind::AAndNotA(name) => format!("Use `False` instead of `{name} and not {name}`"),
-            CheckKind::AOrNotA(name) => format!("Use `True` instead of `{name} or not {name}`"),
+            CheckKind::MultipleWithStatements => "Use a single `with` statement with multiple contexts instead of nested `with` \
+                 statements".to_string(),
+            CheckKind::NestedIfStatements => {
+                "Use a single `if` statement instead of nested `if` statements".to_string()
+            }
             CheckKind::OrTrue => "Use `True` instead of `... or True`".to_string(),
-            CheckKind::AndFalse => "Use `False` instead of `... and False`".to_string(),
             CheckKind::YodaConditions(left, right) => {
                 format!("Yoda conditions are discouraged, use `{left} == {right}` instead")
             }

src/registry_gen.rs

@@ -521,6 +521,7 @@ pub enum CheckCodePrefix {
     SIM102,
     SIM105,
     SIM11,
+    SIM117,
     SIM118,
     SIM2,
     SIM22,
@@ -807,6 +808,7 @@ impl CheckCodePrefix {
                 CheckCode::YTT301,
                 CheckCode::YTT302,
                 CheckCode::YTT303,
+                CheckCode::SIM117,
                 CheckCode::SIM102,
                 CheckCode::SIM105,
                 CheckCode::SIM118,
@@ -2631,6 +2633,7 @@ impl CheckCodePrefix {
             CheckCodePrefix::S107 => vec![CheckCode::S107],
             CheckCodePrefix::S108 => vec![CheckCode::S108],
             CheckCodePrefix::SIM => vec![
+                CheckCode::SIM117,
                 CheckCode::SIM102,
                 CheckCode::SIM105,
                 CheckCode::SIM118,
@@ -2640,11 +2643,17 @@ impl CheckCodePrefix {
                 CheckCode::SIM223,
                 CheckCode::SIM300,
             ],
-            CheckCodePrefix::SIM1 => vec![CheckCode::SIM102, CheckCode::SIM105, CheckCode::SIM118],
+            CheckCodePrefix::SIM1 => vec![
+                CheckCode::SIM117,
+                CheckCode::SIM102,
+                CheckCode::SIM105,
+                CheckCode::SIM118,
+            ],
             CheckCodePrefix::SIM10 => vec![CheckCode::SIM102, CheckCode::SIM105],
             CheckCodePrefix::SIM102 => vec![CheckCode::SIM102],
             CheckCodePrefix::SIM105 => vec![CheckCode::SIM105],
-            CheckCodePrefix::SIM11 => vec![CheckCode::SIM118],
+            CheckCodePrefix::SIM11 => vec![CheckCode::SIM117, CheckCode::SIM118],
+            CheckCodePrefix::SIM117 => vec![CheckCode::SIM117],
             CheckCodePrefix::SIM118 => vec![CheckCode::SIM118],
             CheckCodePrefix::SIM2 => vec![
                 CheckCode::SIM220,
@@ -3619,6 +3628,7 @@ impl CheckCodePrefix {
             CheckCodePrefix::SIM102 => SuffixLength::Three,
             CheckCodePrefix::SIM105 => SuffixLength::Three,
             CheckCodePrefix::SIM11 => SuffixLength::Two,
+            CheckCodePrefix::SIM117 => SuffixLength::Three,
             CheckCodePrefix::SIM118 => SuffixLength::Three,
             CheckCodePrefix::SIM2 => SuffixLength::One,
             CheckCodePrefix::SIM22 => SuffixLength::Two,