Support new extend-per-file-ignores setting (#4265)

crates/ruff/src/settings/configuration.rs

@@ -48,6 +48,7 @@ pub struct Configuration {
     pub extend: Option<PathBuf>,
     pub extend_exclude: Vec<FilePattern>,
     pub extend_include: Vec<FilePattern>,
+    pub extend_per_file_ignores: Vec<PerFileIgnore>,
     pub external: Option<Vec<String>>,
     pub fix: Option<bool>,
     pub fix_only: Option<bool>,
@@ -166,6 +167,17 @@ impl Configuration {
                         .collect()
                 })
                 .unwrap_or_default(),
+            extend_per_file_ignores: options
+                .extend_per_file_ignores
+                .map(|per_file_ignores| {
+                    per_file_ignores
+                        .into_iter()
+                        .map(|(pattern, prefixes)| {
+                            PerFileIgnore::new(pattern, &prefixes, Some(project_root))
+                        })
+                        .collect()
+                })
+                .unwrap_or_default(),
             external: options.external,
             fix: options.fix,
             fix_only: options.fix_only,
@@ -254,6 +266,11 @@ impl Configuration {
                 .into_iter()
                 .chain(self.extend_include.into_iter())
                 .collect(),
+            extend_per_file_ignores: config
+                .extend_per_file_ignores
+                .into_iter()
+                .chain(self.extend_per_file_ignores.into_iter())
+                .collect(),
             external: self.external.or(config.external),
             fix: self.fix.or(config.fix),
             fix_only: self.fix_only.or(config.fix_only),

crates/ruff/src/settings/mod.rs

@@ -163,7 +163,12 @@ impl Settings {
             line_length: config.line_length.unwrap_or(defaults::LINE_LENGTH),
             namespace_packages: config.namespace_packages.unwrap_or_default(),
             per_file_ignores: resolve_per_file_ignores(
-                config.per_file_ignores.unwrap_or_default(),
+                config
+                    .per_file_ignores
+                    .unwrap_or_default()
+                    .into_iter()
+                    .chain(config.extend_per_file_ignores)
+                    .collect(),
             )?,
             respect_gitignore: config.respect_gitignore.unwrap_or(true),
             src: config

crates/ruff/src/settings/options.rs

@@ -541,4 +541,16 @@ pub struct Options {
     /// A list of mappings from file pattern to rule codes or prefixes to
     /// exclude, when considering any matching files.
     pub per_file_ignores: Option<FxHashMap<String, Vec<RuleSelector>>>,
+    #[option(
+        default = "{}",
+        value_type = "dict[str, list[RuleSelector]]",
+        example = r#"
+            # Also ignore `E401` in all `__init__.py` files.
+            [tool.ruff.extend-per-file-ignores]
+            "__init__.py" = ["E402"]
+        "#
+    )]
+    /// A list of mappings from file pattern to rule codes or prefixes to
+    /// exclude, in addition to any rules excluded by `per-file-ignores`.
+    pub extend_per_file_ignores: Option<FxHashMap<String, Vec<RuleSelector>>>,
 }

crates/ruff_cli/src/args.rs

@@ -133,8 +133,8 @@ pub struct CheckArgs {
         hide_possible_values = true
     )]
     pub ignore: Option<Vec<RuleSelector>>,
-    /// Like --select, but adds additional rule codes on top of the selected
+    /// Like --select, but adds additional rule codes on top of those already
-    /// ones.
+    /// specified.
     #[arg(
         long,
         value_delimiter = ',',
@@ -154,9 +154,13 @@ pub struct CheckArgs {
         hide = true
     )]
     pub extend_ignore: Option<Vec<RuleSelector>>,
-    /// List of mappings from file pattern to code to exclude
+    /// List of mappings from file pattern to code to exclude.
     #[arg(long, value_delimiter = ',', help_heading = "Rule selection")]
     pub per_file_ignores: Option<Vec<PatternPrefixPair>>,
+    /// Like `--per-file-ignores`, but adds additional ignores on top of
+    /// those already specified.
+    #[arg(long, value_delimiter = ',', help_heading = "Rule selection")]
+    pub extend_per_file_ignores: Option<Vec<PatternPrefixPair>>,
     /// List of paths, used to omit files and/or directories from analysis.
     #[arg(
         long,
@@ -196,8 +200,8 @@ pub struct CheckArgs {
         hide_possible_values = true
     )]
     pub unfixable: Option<Vec<RuleSelector>>,
-    /// Like --fixable, but adds additional rule codes on top of the fixable
+    /// Like --fixable, but adds additional rule codes on top of those already
-    /// ones.
+    /// specified.
     #[arg(
         long,
         value_delimiter = ',',

crates/ruff_wasm/src/lib.rs

@@ -111,6 +111,7 @@ pub fn defaultSettings() -> Result<JsValue, JsValue> {
         extend: None,
         extend_exclude: None,
         extend_include: None,
+        extend_per_file_ignores: None,
         fix: None,
         fix_only: None,
         fixable: None,

docs/configuration.md

@@ -232,15 +232,17 @@ Rule selection:
       --ignore <RULE_CODE>
           Comma-separated list of rule codes to disable
       --extend-select <RULE_CODE>
-          Like --select, but adds additional rule codes on top of the selected ones
+          Like --select, but adds additional rule codes on top of those already specified
       --per-file-ignores <PER_FILE_IGNORES>
           List of mappings from file pattern to code to exclude
+      --extend-per-file-ignores <EXTEND_PER_FILE_IGNORES>
+          Like `--per-file-ignores`, but adds additional ignores on top of those already specified
       --fixable <RULE_CODE>
           List of rule codes to treat as eligible for autofix. Only applicable when autofix itself is enabled (e.g., via `--fix`)
       --unfixable <RULE_CODE>
           List of rule codes to treat as ineligible for autofix. Only applicable when autofix itself is enabled (e.g., via `--fix`)
       --extend-fixable <RULE_CODE>
-          Like --fixable, but adds additional rule codes on top of the fixable ones
+          Like --fixable, but adds additional rule codes on top of those already specified
 
 File selection:
       --exclude <FILE_PATTERN>         List of paths, used to omit files and/or directories from analysis

ruff.schema.json

@@ -86,6 +86,19 @@
         "type": "string"
       }
     },
+    "extend-per-file-ignores": {
+      "description": "A list of mappings from file pattern to rule codes or prefixes to exclude, in addition to any rules excluded by `per-file-ignores`.",
+      "type": [
+        "object",
+        "null"
+      ],
+      "additionalProperties": {
+        "type": "array",
+        "items": {
+          "$ref": "#/definitions/RuleSelector"
+        }
+      }
+    },
     "extend-select": {
       "description": "A list of rule codes or prefixes to enable, in addition to those specified by `select`.",
       "type": [