Add pyupgrade's --keep-runtime-typing option (#965)

README.md

@@ -1845,6 +1845,26 @@ has no `self` or `cls` argument.
 staticmethod-decorators = ["staticmethod", "stcmthd"]
 ```
 
+### `pyupgrade`
+
+#### [`keep_runtime_typing`](#keep_runtime_typing)
+
+Whether to avoid PEP 585 (`List[int]` -> `list[int]`) and PEP 604 (`Optional[str]` -> `str | None`)
+rewrites even if a file imports `from __future__ import annotations`. Note that this setting is
+only applicable when the target Python version is below 3.9 and 3.10 respectively.
+
+**Default value**: `false`
+
+**Type**: `bool`
+
+**Example usage**:
+
+```toml
+[tool.ruff.pep8-naming]
+# Preserve types, even if a file imports `from __future__ import annotations`.
+keep-runtime-typing = true
+```
+
 ## License
 
 MIT

pyproject.toml

@@ -35,3 +35,6 @@ strip = true
 [tool.isort]
 profile = "black"
 known_third_party = ["fastapi", "pydantic", "starlette"]
+
+[tool.ruff.pyupgrade]
+

src/check_ast.rs

@@ -1197,6 +1197,7 @@ where
                     && self.settings.enabled.contains(&CheckCode::U007)
                     && (self.settings.target_version >= PythonVersion::Py310
                         || (self.settings.target_version >= PythonVersion::Py37
+                            && !self.settings.pyupgrade.keep_runtime_typing
                             && self.annotations_future_enabled
                             && self.in_deferred_annotation))
                 {
@@ -1239,6 +1240,7 @@ where
                             && self.settings.enabled.contains(&CheckCode::U006)
                             && (self.settings.target_version >= PythonVersion::Py39
                                 || (self.settings.target_version >= PythonVersion::Py37
+                                    && !self.settings.pyupgrade.keep_runtime_typing
                                     && self.annotations_future_enabled
                                     && self.in_deferred_annotation))
                             && typing::is_pep585_builtin(

src/flake8_bugbear/settings.rs

@@ -1,4 +1,4 @@
-//! Settings for the `pep8-naming` plugin.
+//! Settings for the `flake8-bugbear` plugin.
 
 use serde::{Deserialize, Serialize};
 

src/pyupgrade/mod.rs

@@ -1,4 +1,5 @@
 mod checks;
 pub mod fixes;
 pub mod plugins;
+pub mod settings;
 pub mod types;

src/pyupgrade/settings.rs

@@ -0,0 +1,22 @@
+//! Settings for the `pyupgrade` plugin.
+
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Default)]
+#[serde(deny_unknown_fields, rename_all = "kebab-case")]
+pub struct Options {
+    pub keep_runtime_typing: Option<bool>,
+}
+
+#[derive(Debug, Hash, Default)]
+pub struct Settings {
+    pub keep_runtime_typing: bool,
+}
+
+impl Settings {
+    pub fn from_options(options: Options) -> Self {
+        Self {
+            keep_runtime_typing: options.keep_runtime_typing.unwrap_or_default(),
+        }
+    }
+}

src/settings/configuration.rs

@@ -14,7 +14,7 @@ use crate::settings::pyproject::load_options;
 use crate::settings::types::{FilePattern, PerFileIgnore, PythonVersion, SerializationFormat};
 use crate::{
     flake8_annotations, flake8_bugbear, flake8_quotes, flake8_tidy_imports, fs, isort, mccabe,
-    pep8_naming,
+    pep8_naming, pyupgrade,
 };
 
 #[derive(Debug)]
@@ -44,6 +44,7 @@ pub struct Configuration {
     pub isort: isort::settings::Settings,
     pub mccabe: mccabe::settings::Settings,
     pub pep8_naming: pep8_naming::settings::Settings,
+    pub pyupgrade: pyupgrade::settings::Settings,
 }
 
 static DEFAULT_EXCLUDE: Lazy<Vec<FilePattern>> = Lazy::new(|| {
@@ -164,6 +165,10 @@ impl Configuration {
                 .pep8_naming
                 .map(pep8_naming::settings::Settings::from_options)
                 .unwrap_or_default(),
+            pyupgrade: options
+                .pyupgrade
+                .map(pyupgrade::settings::Settings::from_options)
+                .unwrap_or_default(),
         })
     }
 }

src/settings/mod.rs

@@ -18,7 +18,7 @@ use crate::settings::configuration::Configuration;
 use crate::settings::types::{FilePattern, PerFileIgnore, PythonVersion, SerializationFormat};
 use crate::{
     flake8_annotations, flake8_bugbear, flake8_quotes, flake8_tidy_imports, fs, isort, mccabe,
-    pep8_naming,
+    pep8_naming, pyupgrade,
 };
 
 pub mod configuration;
@@ -48,6 +48,7 @@ pub struct Settings {
     pub isort: isort::settings::Settings,
     pub mccabe: mccabe::settings::Settings,
     pub pep8_naming: pep8_naming::settings::Settings,
+    pub pyupgrade: pyupgrade::settings::Settings,
 }
 
 impl Settings {
@@ -82,6 +83,7 @@ impl Settings {
             mccabe: config.mccabe,
             line_length: config.line_length,
             pep8_naming: config.pep8_naming,
+            pyupgrade: config.pyupgrade,
             per_file_ignores: resolve_per_file_ignores(config.per_file_ignores, project_root)?,
             src: config.src,
             target_version: config.target_version,
@@ -110,6 +112,7 @@ impl Settings {
             isort: isort::settings::Settings::default(),
             mccabe: mccabe::settings::Settings::default(),
             pep8_naming: pep8_naming::settings::Settings::default(),
+            pyupgrade: pyupgrade::settings::Settings::default(),
         }
     }
 
@@ -134,6 +137,7 @@ impl Settings {
             isort: isort::settings::Settings::default(),
             mccabe: mccabe::settings::Settings::default(),
             pep8_naming: pep8_naming::settings::Settings::default(),
+            pyupgrade: pyupgrade::settings::Settings::default(),
         }
     }
 }
@@ -165,6 +169,7 @@ impl Hash for Settings {
         self.isort.hash(state);
         self.mccabe.hash(state);
         self.pep8_naming.hash(state);
+        self.pyupgrade.hash(state);
     }
 }
 

src/settings/options.rs

@@ -7,7 +7,7 @@ use crate::checks_gen::CheckCodePrefix;
 use crate::settings::types::{PythonVersion, SerializationFormat};
 use crate::{
     flake8_annotations, flake8_bugbear, flake8_quotes, flake8_tidy_imports, isort, mccabe,
-    pep8_naming,
+    pep8_naming, pyupgrade,
 };
 
 #[derive(Debug, PartialEq, Eq, Serialize, Deserialize, Default)]
@@ -37,6 +37,7 @@ pub struct Options {
     pub isort: Option<isort::settings::Options>,
     pub mccabe: Option<mccabe::settings::Options>,
     pub pep8_naming: Option<pep8_naming::settings::Options>,
+    pub pyupgrade: Option<pyupgrade::settings::Options>,
     // Tables are required to go last.
     pub per_file_ignores: Option<FxHashMap<String, Vec<CheckCodePrefix>>>,
 }