[flake8-bugbear] Add pytest.raises(Exception) support to B017 (#4052)

crates/ruff/resources/test/fixtures/flake8_bugbear/B017.py

@@ -1,9 +1,10 @@
 """
 Should emit:
-B017 - on lines 20
+B017 - on lines 23 and 41
 """
 import asyncio
 import unittest
+import pytest
 
 CONSTANT = True
 
@@ -34,3 +35,14 @@ class Foobar(unittest.TestCase):
     def raises_with_absolute_reference(self):
         with self.assertRaises(asyncio.CancelledError):
             Foo()
+
+
+def test_pytest_raises():
+    with pytest.raises(Exception):
+        raise ValueError("Hello")
+
+    with pytest.raises(Exception, "hello"):
+        raise ValueError("This is fine")
+
+    with pytest.raises(Exception, match="hello"):
+        raise ValueError("This is also fine")

crates/ruff/src/rules/flake8_bugbear/rules/assert_raises_exception.rs

@@ -6,15 +6,21 @@ use ruff_python_ast::types::Range;
 
 use crate::checkers::ast::Checker;
 
+#[derive(Debug, PartialEq, Eq)]
+pub enum AssertionKind {
+    AssertRaises,
+    PytestRaises,
+}
+
 /// ## What it does
-/// Checks for `self.assertRaises(Exception)`.
+/// Checks for `self.assertRaises(Exception)` or `pytest.raises(Exception)`.
 ///
 /// ## Why is this bad?
-/// `assertRaises(Exception)` can lead to your test passing even if the
-/// code being tested is never executed due to a typo.
+/// These forms catch every `Exception`, which can lead to tests passing even
+/// if, e.g., the code being tested is never executed due to a typo.
 ///
-/// Either assert for a more specific exception (builtin or custom), use
-/// `assertRaisesRegex` or the context manager form of `assertRaises`.
+/// Either assert for a more specific exception (builtin or custom), or use
+/// `assertRaisesRegex` or `pytest.raises(..., match=<REGEX>)` respectively.
 ///
 /// ## Example
 /// ```python
@@ -26,13 +32,22 @@ use crate::checkers::ast::Checker;
 /// self.assertRaises(SomeSpecificException, foo)
 /// ```
 #[violation]
-pub struct AssertRaisesException;
+pub struct AssertRaisesException {
+    kind: AssertionKind,
+}
 
 impl Violation for AssertRaisesException {
     #[derive_message_formats]
     fn message(&self) -> String {
+        match self.kind {
+            AssertionKind::AssertRaises => {
                 format!("`assertRaises(Exception)` should be considered evil")
             }
+            AssertionKind::PytestRaises => {
+                format!("`pytest.raises(Exception)` should be considered evil")
+            }
+        }
+    }
 }
 
 /// B017
@@ -41,7 +56,7 @@ pub fn assert_raises_exception(checker: &mut Checker, stmt: &Stmt, items: &[With
         return;
     };
     let item_context = &item.context_expr;
-    let ExprKind::Call { func, args, .. } = &item_context.node else {
+    let ExprKind::Call { func, args, keywords } = &item_context.node else {
         return;
     };
     if args.len() != 1 {
@@ -50,9 +65,7 @@ pub fn assert_raises_exception(checker: &mut Checker, stmt: &Stmt, items: &[With
     if item.optional_vars.is_some() {
         return;
     }
-    if !matches!(&func.node, ExprKind::Attribute { attr, .. } if attr == "assertRaises") {
-        return;
-    }
+
     if !checker
         .ctx
         .resolve_call_path(args.first().unwrap())
@@ -61,7 +74,31 @@ pub fn assert_raises_exception(checker: &mut Checker, stmt: &Stmt, items: &[With
         return;
     }
 
-    checker
-        .diagnostics
-        .push(Diagnostic::new(AssertRaisesException, Range::from(stmt)));
+    let kind = {
+        if matches!(&func.node, ExprKind::Attribute { attr, .. } if attr == "assertRaises") {
+            AssertionKind::AssertRaises
+        } else if checker
+            .ctx
+            .resolve_call_path(func)
+            .map_or(false, |call_path| {
+                call_path.as_slice() == ["pytest", "raises"]
+            })
+            && !keywords.iter().any(|keyword| {
+                keyword
+                    .node
+                    .arg
+                    .as_ref()
+                    .map_or(false, |arg| arg == "match")
+            })
+        {
+            AssertionKind::PytestRaises
+        } else {
+            return;
+        }
+    };
+
+    checker.diagnostics.push(Diagnostic::new(
+        AssertRaisesException { kind },
+        Range::from(stmt),
+    ));
 }

crates/ruff/src/rules/flake8_bugbear/snapshots/ruff__rules__flake8_bugbear__tests__B017_B017.py.snap

@@ -1,16 +1,27 @@
 ---
 source: crates/ruff/src/rules/flake8_bugbear/mod.rs
 ---
-B017.py:22:9: B017 `assertRaises(Exception)` should be considered evil
+B017.py:23:9: B017 `assertRaises(Exception)` should be considered evil
    |
-22 |   class Foobar(unittest.TestCase):
-23 |       def evil_raises(self) -> None:
-24 |           with self.assertRaises(Exception):
+23 |   class Foobar(unittest.TestCase):
+24 |       def evil_raises(self) -> None:
+25 |           with self.assertRaises(Exception):
    |  _________^
-25 | |             raise Exception("Evil I say!")
+26 | |             raise Exception("Evil I say!")
    | |__________________________________________^ B017
-26 |   
-27 |       def context_manager_raises(self) -> None:
+27 |   
+28 |       def context_manager_raises(self) -> None:
+   |
+
+B017.py:41:5: B017 `pytest.raises(Exception)` should be considered evil
+   |
+41 |   def test_pytest_raises():
+42 |       with pytest.raises(Exception):
+   |  _____^
+43 | |         raise ValueError("Hello")
+   | |_________________________________^ B017
+44 |   
+45 |       with pytest.raises(Exception, "hello"):
    |