From 7a75702237e6f0bc605d3d8e9470c4ca9f37c69e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lo=C3=AFc=20Riegel?=
 <96702577+LoicRiegel@users.noreply.github.com>
Date: Mon, 8 Sep 2025 18:10:10 +0200
Subject: [PATCH] Ignore deprecated rules unless selected by exact code
 (#20167)

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## Summary

Closes #18349

After this change:
- All deprecated rules are deselected by default
- They are only selected if the user specifically selects them by code,
e.g. `--select UP038`
- Thus, `--select ALL --select UP --select UP0` won't select the
deprecated rule UP038
- Documented the change in version policy. From now on, deprecating a
rule should increase the minor version

## Test Plan

Integration tests in "integration_tests.rs"

Also tested with a temporary test package:
```
~> ../../ruff/target/debug/ruff.exe check --select UP038
warning: Rule `UP038` is deprecated and will be removed in a future release.
warning: Detected debug build without --no-cache.
UP038 Use `X | Y` in `isinstance` call instead of `(X, Y)`
 --> main.py:2:11
  |
1 | def main():
2 |     print(isinstance(25, (str, int)))
  |           ^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
help: Convert to `X | Y`

Found 1 error.
No fixes available (1 hidden fix can be enabled with the `--unsafe-fixes` option).

~> ../../ruff/target/debug/ruff.exe check --select UP03
warning: Detected debug build without --no-cache.
All checks passed!

~> ../../ruff/target/debug/ruff.exe check --select UP0
warning: Detected debug build without --no-cache.
All checks passed!

~> ../../ruff/target/debug/ruff.exe check --select UP
warning: Detected debug build without --no-cache.
All checks passed!

~> ../../ruff/target/debug/ruff.exe check --select ALL
# warnings and errors, but because of other errors, UP038 was deselected
```
---
 crates/ruff/tests/integration_test.rs   | 22 ++++++----------------
 crates/ruff_linter/src/rule_selector.rs |  6 ++----
 docs/versioning.md                      |  1 +
 3 files changed, 9 insertions(+), 20 deletions(-)

diff --git a/crates/ruff/tests/integration_test.rs b/crates/ruff/tests/integration_test.rs
index f9122e3b5e..4babbb3986 100644
--- a/crates/ruff/tests/integration_test.rs
+++ b/crates/ruff/tests/integration_test.rs
@@ -1489,6 +1489,8 @@ fn deprecated_direct() {
 
 #[test]
 fn deprecated_multiple_direct() {
+    // Multiple deprecated rules selected by exact code should be included
+    // but a warning should be displayed
     let mut cmd = RuffCheck::default()
         .args(["--select", "RUF920", "--select", "RUF921"])
         .build();
@@ -1516,16 +1518,10 @@ fn deprecated_indirect() {
     // since it is not a "direct" selection
     let mut cmd = RuffCheck::default().args(["--select", "RUF92"]).build();
     assert_cmd_snapshot!(cmd, @r"
-    success: false
-    exit_code: 1
+    success: true
+    exit_code: 0
     ----- stdout -----
-    RUF920 Hey this is a deprecated test rule.
-    --> -:1:1
-
-    RUF921 Hey this is another deprecated test rule.
-    --> -:1:1
-
-    Found 2 errors.
+    All checks passed!
 
     ----- stderr -----
     ");
@@ -2155,16 +2151,10 @@ extend-safe-fixes = ["RUF9"]
     RUF903 Hey this is a stable test rule with a display only fix.
     --> -:1:1
 
-    RUF920 Hey this is a deprecated test rule.
-    --> -:1:1
-
-    RUF921 Hey this is another deprecated test rule.
-    --> -:1:1
-
     RUF950 Hey this is a test rule that was redirected from another.
     --> -:1:1
 
-    Found 7 errors.
+    Found 5 errors.
     [*] 1 fixable with the `--fix` option (1 hidden fix can be enabled with the `--unsafe-fixes` option).
 
     ----- stderr -----
diff --git a/crates/ruff_linter/src/rule_selector.rs b/crates/ruff_linter/src/rule_selector.rs
index 74f069b976..399c881a34 100644
--- a/crates/ruff_linter/src/rule_selector.rs
+++ b/crates/ruff_linter/src/rule_selector.rs
@@ -214,10 +214,8 @@ impl RuleSelector {
                 RuleGroup::Preview => {
                     preview_enabled && (self.is_exact() || !preview_require_explicit)
                 }
-                // Deprecated rules are excluded in preview mode and with 'All' option unless explicitly selected
-                RuleGroup::Deprecated => {
-                    (!preview_enabled || self.is_exact()) && !matches!(self, RuleSelector::All)
-                }
+                // Deprecated rules are excluded by default unless explicitly selected
+                RuleGroup::Deprecated => !preview_enabled && self.is_exact(),
                 // Removed rules are included if explicitly selected but will error downstream
                 RuleGroup::Removed => self.is_exact(),
             }
diff --git a/docs/versioning.md b/docs/versioning.md
index 2740cf2b6e..6c6ad920ba 100644
--- a/docs/versioning.md
+++ b/docs/versioning.md
@@ -20,6 +20,7 @@ Ruff uses a custom versioning scheme that uses the **minor** version number for
     - Stable rules are added to the default set
     - Stable rules are removed from the default set
     - A safe fix for a rule is promoted to stable
+    - A rule is deprecated
 - Formatter:
      - The stable style changed
 - Language server: