clippy_config/
conf.rs

1use crate::ClippyConfiguration;
2use crate::types::{
3    DisallowedPath, DisallowedPathWithoutReplacement, InherentImplLintScope, MacroMatcher, MatchLintBehaviour,
4    PubUnderscoreFieldsBehaviour, Rename, SourceItemOrdering, SourceItemOrderingCategory,
5    SourceItemOrderingModuleItemGroupings, SourceItemOrderingModuleItemKind, SourceItemOrderingTraitAssocItemKind,
6    SourceItemOrderingTraitAssocItemKinds, SourceItemOrderingWithinModuleItemGroupings,
7};
8use clippy_utils::msrvs::Msrv;
9use itertools::Itertools;
10use rustc_errors::Applicability;
11use rustc_session::Session;
12use rustc_span::edit_distance::edit_distance;
13use rustc_span::{BytePos, Pos, SourceFile, Span, SyntaxContext};
14use serde::de::{IgnoredAny, IntoDeserializer, MapAccess, Visitor};
15use serde::{Deserialize, Deserializer, Serialize};
16use std::collections::HashMap;
17use std::fmt::{Debug, Display, Formatter};
18use std::ops::Range;
19use std::path::PathBuf;
20use std::str::FromStr;
21use std::sync::OnceLock;
22use std::{cmp, env, fmt, fs, io};
23
24#[rustfmt::skip]
25const DEFAULT_DOC_VALID_IDENTS: &[&str] = &[
26    "KiB", "MiB", "GiB", "TiB", "PiB", "EiB",
27    "MHz", "GHz", "THz",
28    "AccessKit",
29    "CoAP", "CoreFoundation", "CoreGraphics", "CoreText",
30    "DevOps",
31    "Direct2D", "Direct3D", "DirectWrite", "DirectX",
32    "ECMAScript",
33    "GPLv2", "GPLv3",
34    "GitHub", "GitLab",
35    "IPv4", "IPv6",
36    "InfiniBand", "RoCE",
37    "ClojureScript", "CoffeeScript", "JavaScript", "PostScript", "PureScript", "TypeScript",
38    "PowerPC", "WebAssembly",
39    "NaN", "NaNs",
40    "OAuth", "GraphQL",
41    "OCaml",
42    "OpenAL", "OpenDNS", "OpenGL", "OpenMP", "OpenSSH", "OpenSSL", "OpenStreetMap", "OpenTelemetry",
43    "OpenType",
44    "WebGL", "WebGL2", "WebGPU", "WebRTC", "WebSocket", "WebTransport",
45    "WebP", "OpenExr", "YCbCr", "sRGB",
46    "TensorFlow",
47    "TrueType",
48    "iOS", "macOS", "FreeBSD", "NetBSD", "OpenBSD", "NixOS",
49    "TeX", "LaTeX", "BibTeX", "BibLaTeX",
50    "MinGW",
51    "CamelCase",
52];
53const DEFAULT_DISALLOWED_NAMES: &[&str] = &["foo", "baz", "quux"];
54const DEFAULT_ALLOWED_IDENTS_BELOW_MIN_CHARS: &[&str] = &["i", "j", "x", "y", "z", "w", "n"];
55const DEFAULT_ALLOWED_PREFIXES: &[&str] = &["to", "as", "into", "from", "try_into", "try_from"];
56const DEFAULT_ALLOWED_TRAITS_WITH_RENAMED_PARAMS: &[&str] =
57    &["core::convert::From", "core::convert::TryFrom", "core::str::FromStr"];
58const DEFAULT_MODULE_ITEM_ORDERING_GROUPS: &[(&str, &[SourceItemOrderingModuleItemKind])] = {
59    #[allow(clippy::enum_glob_use)] // Very local glob use for legibility.
60    use SourceItemOrderingModuleItemKind::*;
61    &[
62        ("modules", &[ExternCrate, Mod, ForeignMod]),
63        ("use", &[Use]),
64        ("macros", &[Macro]),
65        ("global_asm", &[GlobalAsm]),
66        ("UPPER_SNAKE_CASE", &[Static, Const]),
67        ("PascalCase", &[TyAlias, Enum, Struct, Union, Trait, TraitAlias, Impl]),
68        ("lower_snake_case", &[Fn]),
69    ]
70};
71const DEFAULT_TRAIT_ASSOC_ITEM_KINDS_ORDER: &[SourceItemOrderingTraitAssocItemKind] = {
72    #[allow(clippy::enum_glob_use)] // Very local glob use for legibility.
73    use SourceItemOrderingTraitAssocItemKind::*;
74    &[Const, Type, Fn]
75};
76const DEFAULT_SOURCE_ITEM_ORDERING: &[SourceItemOrderingCategory] = {
77    #[allow(clippy::enum_glob_use)] // Very local glob use for legibility.
78    use SourceItemOrderingCategory::*;
79    &[Enum, Impl, Module, Struct, Trait]
80};
81
82/// Conf with parse errors
83#[derive(Default)]
84struct TryConf {
85    conf: Conf,
86    value_spans: HashMap<String, Range<usize>>,
87    errors: Vec<ConfError>,
88    warnings: Vec<ConfError>,
89}
90
91impl TryConf {
92    fn from_toml_error(file: &SourceFile, error: &toml::de::Error) -> Self {
93        Self {
94            conf: Conf::default(),
95            value_spans: HashMap::default(),
96            errors: vec![ConfError::from_toml(file, error)],
97            warnings: vec![],
98        }
99    }
100}
101
102#[derive(Debug)]
103struct ConfError {
104    message: String,
105    suggestion: Option<Suggestion>,
106    span: Span,
107}
108
109impl ConfError {
110    fn from_toml(file: &SourceFile, error: &toml::de::Error) -> Self {
111        let span = error.span().unwrap_or(0..file.normalized_source_len.0 as usize);
112        Self::spanned(file, error.message(), None, span)
113    }
114
115    fn spanned(
116        file: &SourceFile,
117        message: impl Into<String>,
118        suggestion: Option<Suggestion>,
119        span: Range<usize>,
120    ) -> Self {
121        Self {
122            message: message.into(),
123            suggestion,
124            span: span_from_toml_range(file, span),
125        }
126    }
127}
128
129// Remove code tags and code behind '# 's, as they are not needed for the lint docs and --explain
130pub fn sanitize_explanation(raw_docs: &str) -> String {
131    // Remove tags and hidden code:
132    let mut explanation = String::with_capacity(128);
133    let mut in_code = false;
134    for line in raw_docs.lines() {
135        let line = line.strip_prefix(' ').unwrap_or(line);
136
137        if let Some(lang) = line.strip_prefix("```") {
138            let tag = lang.split_once(',').map_or(lang, |(left, _)| left);
139            if !in_code && matches!(tag, "" | "rust" | "ignore" | "should_panic" | "no_run" | "compile_fail") {
140                explanation += "```rust\n";
141            } else {
142                explanation += line;
143                explanation.push('\n');
144            }
145            in_code = !in_code;
146        } else if !(in_code && line.starts_with("# ")) {
147            explanation += line;
148            explanation.push('\n');
149        }
150    }
151
152    explanation
153}
154
155macro_rules! wrap_option {
156    () => {
157        None
158    };
159    ($x:literal) => {
160        Some($x)
161    };
162}
163
164macro_rules! default_text {
165    ($value:expr) => {{
166        let mut text = String::new();
167        $value.serialize(toml::ser::ValueSerializer::new(&mut text)).unwrap();
168        text
169    }};
170    ($value:expr, $override:expr) => {
171        $override.to_string()
172    };
173}
174
175macro_rules! deserialize {
176    ($map:expr, $ty:ty, $errors:expr, $file:expr) => {{
177        let raw_value = $map.next_value::<toml::Spanned<toml::Value>>()?;
178        let value_span = raw_value.span();
179        let value = match <$ty>::deserialize(raw_value.into_inner()) {
180            Err(e) => {
181                $errors.push(ConfError::spanned(
182                    $file,
183                    e.to_string().replace('\n', " ").trim(),
184                    None,
185                    value_span,
186                ));
187                continue;
188            },
189            Ok(value) => value,
190        };
191        (value, value_span)
192    }};
193
194    ($map:expr, $ty:ty, $errors:expr, $file:expr, $replacements_allowed:expr) => {{
195        let array = $map.next_value::<Vec<toml::Spanned<toml::Value>>>()?;
196        let mut disallowed_paths_span = Range {
197            start: usize::MAX,
198            end: usize::MIN,
199        };
200        let mut disallowed_paths = Vec::new();
201        for raw_value in array {
202            let value_span = raw_value.span();
203            let mut disallowed_path = match DisallowedPath::<$replacements_allowed>::deserialize(raw_value.into_inner())
204            {
205                Err(e) => {
206                    $errors.push(ConfError::spanned(
207                        $file,
208                        e.to_string().replace('\n', " ").trim(),
209                        None,
210                        value_span,
211                    ));
212                    continue;
213                },
214                Ok(disallowed_path) => disallowed_path,
215            };
216            disallowed_paths_span = union(&disallowed_paths_span, &value_span);
217            disallowed_path.set_span(span_from_toml_range($file, value_span));
218            disallowed_paths.push(disallowed_path);
219        }
220        (disallowed_paths, disallowed_paths_span)
221    }};
222}
223
224macro_rules! define_Conf {
225    ($(
226        $(#[doc = $doc:literal])+
227        $(#[conf_deprecated($dep:literal, $new_conf:ident)])?
228        $(#[default_text = $default_text:expr])?
229        $(#[disallowed_paths_allow_replacements = $replacements_allowed:expr])?
230        $(#[lints($($for_lints:ident),* $(,)?)])?
231        $name:ident: $ty:ty = $default:expr,
232    )*) => {
233        /// Clippy lint configuration
234        pub struct Conf {
235            $($(#[cfg_attr(doc, doc = $doc)])+ pub $name: $ty,)*
236        }
237
238        mod defaults {
239            use super::*;
240            $(pub fn $name() -> $ty { $default })*
241        }
242
243        impl Default for Conf {
244            fn default() -> Self {
245                Self { $($name: defaults::$name(),)* }
246            }
247        }
248
249        #[derive(Deserialize)]
250        #[serde(field_identifier, rename_all = "kebab-case")]
251        #[expect(non_camel_case_types)]
252        enum Field { $($name,)* third_party, }
253
254        struct ConfVisitor<'a>(&'a SourceFile);
255
256        impl<'de> Visitor<'de> for ConfVisitor<'_> {
257            type Value = TryConf;
258
259            fn expecting(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
260                formatter.write_str("Conf")
261            }
262
263            fn visit_map<V>(self, mut map: V) -> Result<Self::Value, V::Error> where V: MapAccess<'de> {
264                let mut value_spans = HashMap::new();
265                let mut errors = Vec::new();
266                let mut warnings = Vec::new();
267
268                // Declare a local variable for each field available to a configuration file.
269                $(let mut $name = None;)*
270
271                // could get `Field` here directly, but get `String` first for diagnostics
272                while let Some(name) = map.next_key::<toml::Spanned<String>>()? {
273                    let field = match Field::deserialize(name.get_ref().as_str().into_deserializer()) {
274                        Err(e) => {
275                            let e: FieldError = e;
276                            errors.push(ConfError::spanned(self.0, e.error, e.suggestion, name.span()));
277                            continue;
278                        }
279                        Ok(field) => field
280                    };
281
282                    match field {
283                        $(Field::$name => {
284                            // Is this a deprecated field, i.e., is `$dep` set? If so, push a warning.
285                            $(warnings.push(ConfError::spanned(self.0, format!("deprecated field `{}`. {}", name.get_ref(), $dep), None, name.span()));)?
286                            let (value, value_span) =
287                                deserialize!(map, $ty, errors, self.0 $(, $replacements_allowed)?);
288                            // Was this field set previously?
289                            if $name.is_some() {
290                                errors.push(ConfError::spanned(self.0, format!("duplicate field `{}`", name.get_ref()), None, name.span()));
291                                continue;
292                            }
293                            $name = Some(value);
294                            value_spans.insert(name.get_ref().as_str().to_string(), value_span);
295                            // If this is a deprecated field, was the new field (`$new_conf`) set previously?
296                            // Note that `$new_conf` is one of the defined `$name`s.
297                            $(match $new_conf {
298                                Some(_) => errors.push(ConfError::spanned(self.0, concat!(
299                                    "duplicate field `", stringify!($new_conf),
300                                    "` (provided as `", stringify!($name), "`)"
301                                ), None, name.span())),
302                                None => $new_conf = $name.clone(),
303                            })?
304                        })*
305                        // ignore contents of the third_party key
306                        Field::third_party => drop(map.next_value::<IgnoredAny>())
307                    }
308                }
309                let conf = Conf { $($name: $name.unwrap_or_else(defaults::$name),)* };
310                Ok(TryConf { conf, value_spans, errors, warnings })
311            }
312        }
313
314        pub fn get_configuration_metadata() -> Vec<ClippyConfiguration> {
315            vec![$(
316                ClippyConfiguration {
317                    name: stringify!($name).replace('_', "-"),
318                    default: default_text!(defaults::$name() $(, $default_text)?),
319                    lints: &[$($(stringify!($for_lints)),*)?],
320                    doc: concat!($($doc, '\n',)*),
321                    deprecation_reason: wrap_option!($($dep)?)
322                },
323            )*]
324        }
325    };
326}
327
328fn union(x: &Range<usize>, y: &Range<usize>) -> Range<usize> {
329    Range {
330        start: cmp::min(x.start, y.start),
331        end: cmp::max(x.end, y.end),
332    }
333}
334
335fn span_from_toml_range(file: &SourceFile, span: Range<usize>) -> Span {
336    Span::new(
337        file.start_pos + BytePos::from_usize(span.start),
338        file.start_pos + BytePos::from_usize(span.end),
339        SyntaxContext::root(),
340        None,
341    )
342}
343
344define_Conf! {
345    /// Which crates to allow absolute paths from
346    #[lints(absolute_paths)]
347    absolute_paths_allowed_crates: Vec<String> = Vec::new(),
348    /// The maximum number of segments a path can have before being linted, anything above this will
349    /// be linted.
350    #[lints(absolute_paths)]
351    absolute_paths_max_segments: u64 = 2,
352    /// Whether to accept a safety comment to be placed above the attributes for the `unsafe` block
353    #[lints(undocumented_unsafe_blocks)]
354    accept_comment_above_attributes: bool = true,
355    /// Whether to accept a safety comment to be placed above the statement containing the `unsafe` block
356    #[lints(undocumented_unsafe_blocks)]
357    accept_comment_above_statement: bool = true,
358    /// Don't lint when comparing the result of a modulo operation to zero.
359    #[lints(modulo_arithmetic)]
360    allow_comparison_to_zero: bool = true,
361    /// Whether `dbg!` should be allowed in test functions or `#[cfg(test)]`
362    #[lints(dbg_macro)]
363    allow_dbg_in_tests: bool = false,
364    /// Whether an item should be allowed to have the same name as its containing module
365    #[lints(module_name_repetitions)]
366    allow_exact_repetitions: bool = true,
367    /// Whether `expect` should be allowed in code always evaluated at compile time
368    #[lints(expect_used)]
369    allow_expect_in_consts: bool = true,
370    /// Whether `expect` should be allowed in test functions or `#[cfg(test)]`
371    #[lints(expect_used)]
372    allow_expect_in_tests: bool = false,
373    /// Whether `indexing_slicing` should be allowed in test functions or `#[cfg(test)]`
374    #[lints(indexing_slicing)]
375    allow_indexing_slicing_in_tests: bool = false,
376    /// Whether to allow mixed uninlined format args, e.g. `format!("{} {}", a, foo.bar)`
377    #[lints(uninlined_format_args)]
378    allow_mixed_uninlined_format_args: bool = true,
379    /// Whether to allow `r#""#` when `r""` can be used
380    #[lints(needless_raw_string_hashes)]
381    allow_one_hash_in_raw_strings: bool = false,
382    /// Whether `panic` should be allowed in test functions or `#[cfg(test)]`
383    #[lints(panic)]
384    allow_panic_in_tests: bool = false,
385    /// Whether print macros (ex. `println!`) should be allowed in test functions or `#[cfg(test)]`
386    #[lints(print_stderr, print_stdout)]
387    allow_print_in_tests: bool = false,
388    /// Whether to allow module inception if it's not public.
389    #[lints(module_inception)]
390    allow_private_module_inception: bool = false,
391    /// List of trait paths to ignore when checking renamed function parameters.
392    ///
393    /// #### Example
394    ///
395    /// ```toml
396    /// allow-renamed-params-for = [ "std::convert::From" ]
397    /// ```
398    ///
399    /// #### Noteworthy
400    ///
401    /// - By default, the following traits are ignored: `From`, `TryFrom`, `FromStr`
402    /// - `".."` can be used as part of the list to indicate that the configured values should be appended to the
403    /// default configuration of Clippy. By default, any configuration will replace the default value.
404    #[lints(renamed_function_params)]
405    allow_renamed_params_for: Vec<String> =
406        DEFAULT_ALLOWED_TRAITS_WITH_RENAMED_PARAMS.iter().map(ToString::to_string).collect(),
407    /// Whether `unwrap` should be allowed in code always evaluated at compile time
408    #[lints(unwrap_used)]
409    allow_unwrap_in_consts: bool = true,
410    /// Whether `unwrap` should be allowed in test functions or `#[cfg(test)]`
411    #[lints(unwrap_used)]
412    allow_unwrap_in_tests: bool = false,
413    /// Whether `useless_vec` should ignore test functions or `#[cfg(test)]`
414    #[lints(useless_vec)]
415    allow_useless_vec_in_tests: bool = false,
416    /// Additional dotfiles (files or directories starting with a dot) to allow
417    #[lints(path_ends_with_ext)]
418    allowed_dotfiles: Vec<String> = Vec::default(),
419    /// A list of crate names to allow duplicates of
420    #[lints(multiple_crate_versions)]
421    allowed_duplicate_crates: Vec<String> = Vec::new(),
422    /// Allowed names below the minimum allowed characters. The value `".."` can be used as part of
423    /// the list to indicate, that the configured values should be appended to the default
424    /// configuration of Clippy. By default, any configuration will replace the default value.
425    #[lints(min_ident_chars)]
426    allowed_idents_below_min_chars: Vec<String> =
427        DEFAULT_ALLOWED_IDENTS_BELOW_MIN_CHARS.iter().map(ToString::to_string).collect(),
428    /// List of prefixes to allow when determining whether an item's name ends with the module's name.
429    /// If the rest of an item's name is an allowed prefix (e.g. item `ToFoo` or `to_foo` in module `foo`),
430    /// then don't emit a warning.
431    ///
432    /// #### Example
433    ///
434    /// ```toml
435    /// allowed-prefixes = [ "to", "from" ]
436    /// ```
437    ///
438    /// #### Noteworthy
439    ///
440    /// - By default, the following prefixes are allowed: `to`, `as`, `into`, `from`, `try_into` and `try_from`
441    /// - PascalCase variant is included automatically for each snake_case variant (e.g. if `try_into` is included,
442    ///   `TryInto` will also be included)
443    /// - Use `".."` as part of the list to indicate that the configured values should be appended to the
444    /// default configuration of Clippy. By default, any configuration will replace the default value
445    #[lints(module_name_repetitions)]
446    allowed_prefixes: Vec<String> = DEFAULT_ALLOWED_PREFIXES.iter().map(ToString::to_string).collect(),
447    /// The list of unicode scripts allowed to be used in the scope.
448    #[lints(disallowed_script_idents)]
449    allowed_scripts: Vec<String> = vec!["Latin".to_string()],
450    /// List of path segments allowed to have wildcard imports.
451    ///
452    /// #### Example
453    ///
454    /// ```toml
455    /// allowed-wildcard-imports = [ "utils", "common" ]
456    /// ```
457    ///
458    /// #### Noteworthy
459    ///
460    /// 1. This configuration has no effects if used with `warn_on_all_wildcard_imports = true`.
461    /// 2. Paths with any segment that containing the word 'prelude'
462    /// are already allowed by default.
463    #[lints(wildcard_imports)]
464    allowed_wildcard_imports: Vec<String> = Vec::new(),
465    /// Suppress checking of the passed type names in all types of operations.
466    ///
467    /// If a specific operation is desired, consider using `arithmetic_side_effects_allowed_binary` or `arithmetic_side_effects_allowed_unary` instead.
468    ///
469    /// #### Example
470    ///
471    /// ```toml
472    /// arithmetic-side-effects-allowed = ["SomeType", "AnotherType"]
473    /// ```
474    ///
475    /// #### Noteworthy
476    ///
477    /// A type, say `SomeType`, listed in this configuration has the same behavior of
478    /// `["SomeType" , "*"], ["*", "SomeType"]` in `arithmetic_side_effects_allowed_binary`.
479    #[lints(arithmetic_side_effects)]
480    arithmetic_side_effects_allowed: Vec<String> = <_>::default(),
481    /// Suppress checking of the passed type pair names in binary operations like addition or
482    /// multiplication.
483    ///
484    /// Supports the "*" wildcard to indicate that a certain type won't trigger the lint regardless
485    /// of the involved counterpart. For example, `["SomeType", "*"]` or `["*", "AnotherType"]`.
486    ///
487    /// Pairs are asymmetric, which means that `["SomeType", "AnotherType"]` is not the same as
488    /// `["AnotherType", "SomeType"]`.
489    ///
490    /// #### Example
491    ///
492    /// ```toml
493    /// arithmetic-side-effects-allowed-binary = [["SomeType" , "f32"], ["AnotherType", "*"]]
494    /// ```
495    #[lints(arithmetic_side_effects)]
496    arithmetic_side_effects_allowed_binary: Vec<(String, String)> = <_>::default(),
497    /// Suppress checking of the passed type names in unary operations like "negation" (`-`).
498    ///
499    /// #### Example
500    ///
501    /// ```toml
502    /// arithmetic-side-effects-allowed-unary = ["SomeType", "AnotherType"]
503    /// ```
504    #[lints(arithmetic_side_effects)]
505    arithmetic_side_effects_allowed_unary: Vec<String> = <_>::default(),
506    /// The maximum allowed size for arrays on the stack
507    #[lints(large_const_arrays, large_stack_arrays)]
508    array_size_threshold: u64 = 16 * 1024,
509    /// Suppress lints whenever the suggested change would cause breakage for other crates.
510    #[lints(
511        box_collection,
512        enum_variant_names,
513        large_types_passed_by_value,
514        linkedlist,
515        needless_pass_by_ref_mut,
516        option_option,
517        owned_cow,
518        rc_buffer,
519        rc_mutex,
520        redundant_allocation,
521        ref_option,
522        single_call_fn,
523        trivially_copy_pass_by_ref,
524        unnecessary_box_returns,
525        unnecessary_wraps,
526        unused_self,
527        upper_case_acronyms,
528        vec_box,
529        wrong_self_convention,
530    )]
531    avoid_breaking_exported_api: bool = true,
532    /// The list of types which may not be held across an await point.
533    #[disallowed_paths_allow_replacements = false]
534    #[lints(await_holding_invalid_type)]
535    await_holding_invalid_types: Vec<DisallowedPathWithoutReplacement> = Vec::new(),
536    /// DEPRECATED LINT: BLACKLISTED_NAME.
537    ///
538    /// Use the Disallowed Names lint instead
539    #[conf_deprecated("Please use `disallowed-names` instead", disallowed_names)]
540    blacklisted_names: Vec<String> = Vec::new(),
541    /// For internal testing only, ignores the current `publish` settings in the Cargo manifest.
542    #[lints(cargo_common_metadata)]
543    cargo_ignore_publish: bool = false,
544    /// Whether to check MSRV compatibility in `#[test]` and `#[cfg(test)]` code.
545    #[lints(incompatible_msrv)]
546    check_incompatible_msrv_in_tests: bool = false,
547    /// Whether to suggest reordering constructor fields when initializers are present.
548    ///
549    /// Warnings produced by this configuration aren't necessarily fixed by just reordering the fields. Even if the
550    /// suggested code would compile, it can change semantics if the initializer expressions have side effects. The
551    /// following example [from rust-clippy#11846] shows how the suggestion can run into borrow check errors:
552    ///
553    /// ```rust
554    /// struct MyStruct {
555    ///     vector: Vec<u32>,
556    ///     length: usize
557    /// }
558    /// fn main() {
559    ///     let vector = vec![1,2,3];
560    ///     MyStruct { length: vector.len(), vector};
561    /// }
562    /// ```
563    ///
564    /// [from rust-clippy#11846]: https://github.com/rust-lang/rust-clippy/issues/11846#issuecomment-1820747924
565    #[lints(inconsistent_struct_constructor)]
566    check_inconsistent_struct_field_initializers: bool = false,
567    /// Whether to also run the listed lints on private items.
568    #[lints(missing_errors_doc, missing_panics_doc, missing_safety_doc, unnecessary_safety_doc)]
569    check_private_items: bool = false,
570    /// The maximum cognitive complexity a function can have
571    #[lints(cognitive_complexity)]
572    cognitive_complexity_threshold: u64 = 25,
573    /// The minimum digits a const float literal must have to supress the `excessive_precicion` lint
574    #[lints(excessive_precision)]
575    const_literal_digits_threshold: usize = 30,
576    /// DEPRECATED LINT: CYCLOMATIC_COMPLEXITY.
577    ///
578    /// Use the Cognitive Complexity lint instead.
579    #[conf_deprecated("Please use `cognitive-complexity-threshold` instead", cognitive_complexity_threshold)]
580    cyclomatic_complexity_threshold: u64 = 25,
581    /// The list of disallowed macros, written as fully qualified paths.
582    ///
583    /// **Fields:**
584    /// - `path` (required): the fully qualified path to the macro that should be disallowed
585    /// - `reason` (optional): explanation why this macro is disallowed
586    /// - `replacement` (optional): suggested alternative macro
587    /// - `allow-invalid` (optional, `false` by default): when set to `true`, it will ignore this entry
588    ///   if the path doesn't exist, instead of emitting an error
589    #[disallowed_paths_allow_replacements = true]
590    #[lints(disallowed_macros)]
591    disallowed_macros: Vec<DisallowedPath> = Vec::new(),
592    /// The list of disallowed methods, written as fully qualified paths.
593    ///
594    /// **Fields:**
595    /// - `path` (required): the fully qualified path to the method that should be disallowed
596    /// - `reason` (optional): explanation why this method is disallowed
597    /// - `replacement` (optional): suggested alternative method
598    /// - `allow-invalid` (optional, `false` by default): when set to `true`, it will ignore this entry
599    ///   if the path doesn't exist, instead of emitting an error
600    #[disallowed_paths_allow_replacements = true]
601    #[lints(disallowed_methods)]
602    disallowed_methods: Vec<DisallowedPath> = Vec::new(),
603    /// The list of disallowed names to lint about. NB: `bar` is not here since it has legitimate uses. The value
604    /// `".."` can be used as part of the list to indicate that the configured values should be appended to the
605    /// default configuration of Clippy. By default, any configuration will replace the default value.
606    #[lints(disallowed_names)]
607    disallowed_names: Vec<String> = DEFAULT_DISALLOWED_NAMES.iter().map(ToString::to_string).collect(),
608    /// The list of disallowed types, written as fully qualified paths.
609    ///
610    /// **Fields:**
611    /// - `path` (required): the fully qualified path to the type that should be disallowed
612    /// - `reason` (optional): explanation why this type is disallowed
613    /// - `replacement` (optional): suggested alternative type
614    /// - `allow-invalid` (optional, `false` by default): when set to `true`, it will ignore this entry
615    ///   if the path doesn't exist, instead of emitting an error
616    #[disallowed_paths_allow_replacements = true]
617    #[lints(disallowed_types)]
618    disallowed_types: Vec<DisallowedPath> = Vec::new(),
619    /// The list of words this lint should not consider as identifiers needing ticks. The value
620    /// `".."` can be used as part of the list to indicate, that the configured values should be appended to the
621    /// default configuration of Clippy. By default, any configuration will replace the default value. For example:
622    /// * `doc-valid-idents = ["ClipPy"]` would replace the default list with `["ClipPy"]`.
623    /// * `doc-valid-idents = ["ClipPy", ".."]` would append `ClipPy` to the default list.
624    #[lints(doc_markdown)]
625    doc_valid_idents: Vec<String> = DEFAULT_DOC_VALID_IDENTS.iter().map(ToString::to_string).collect(),
626    /// Whether to apply the raw pointer heuristic to determine if a type is `Send`.
627    #[lints(non_send_fields_in_send_ty)]
628    enable_raw_pointer_heuristic_for_send: bool = true,
629    /// Whether to recommend using implicit into iter for reborrowed values.
630    ///
631    /// #### Example
632    /// ```no_run
633    /// let mut vec = vec![1, 2, 3];
634    /// let rmvec = &mut vec;
635    /// for _ in rmvec.iter() {}
636    /// for _ in rmvec.iter_mut() {}
637    /// ```
638    ///
639    /// Use instead:
640    /// ```no_run
641    /// let mut vec = vec![1, 2, 3];
642    /// let rmvec = &mut vec;
643    /// for _ in &*rmvec {}
644    /// for _ in &mut *rmvec {}
645    /// ```
646    #[lints(explicit_iter_loop)]
647    enforce_iter_loop_reborrow: bool = false,
648    /// The list of imports to always rename, a fully qualified path followed by the rename.
649    #[lints(missing_enforced_import_renames)]
650    enforced_import_renames: Vec<Rename> = Vec::new(),
651    /// The minimum number of enum variants for the lints about variant names to trigger
652    #[lints(enum_variant_names)]
653    enum_variant_name_threshold: u64 = 3,
654    /// The maximum size of an enum's variant to avoid box suggestion
655    #[lints(large_enum_variant)]
656    enum_variant_size_threshold: u64 = 200,
657    /// The maximum amount of nesting a block can reside in
658    #[lints(excessive_nesting)]
659    excessive_nesting_threshold: u64 = 0,
660    /// The maximum byte size a `Future` can have, before it triggers the `clippy::large_futures` lint
661    #[lints(large_futures)]
662    future_size_threshold: u64 = 16 * 1024,
663    /// A list of paths to types that should be treated as if they do not contain interior mutability
664    #[lints(borrow_interior_mutable_const, declare_interior_mutable_const, ifs_same_cond, mutable_key_type)]
665    ignore_interior_mutability: Vec<String> = Vec::from(["bytes::Bytes".into()]),
666    /// Sets the scope ("crate", "file", or "module") in which duplicate inherent `impl` blocks for the same type are linted.
667    #[lints(multiple_inherent_impl)]
668    inherent_impl_lint_scope: InherentImplLintScope = InherentImplLintScope::Crate,
669    /// A list of paths to types that should be ignored as overly large `Err`-variants in a
670    /// `Result` returned from a function
671    #[lints(result_large_err)]
672    large_error_ignored: Vec<String> = Vec::default(),
673    /// The maximum size of the `Err`-variant in a `Result` returned from a function
674    #[lints(result_large_err)]
675    large_error_threshold: u64 = 128,
676    /// Whether collapsible `if` and `else if` chains are linted if they contain comments inside the parts
677    /// that would be collapsed.
678    #[lints(collapsible_else_if, collapsible_if)]
679    lint_commented_code: bool = false,
680    /// Whether to suggest reordering constructor fields when initializers are present.
681    /// DEPRECATED CONFIGURATION: lint-inconsistent-struct-field-initializers
682    ///
683    /// Use the `check-inconsistent-struct-field-initializers` configuration instead.
684    #[conf_deprecated("Please use `check-inconsistent-struct-field-initializers` instead", check_inconsistent_struct_field_initializers)]
685    lint_inconsistent_struct_field_initializers: bool = false,
686    /// The lower bound for linting decimal literals
687    #[lints(decimal_literal_representation)]
688    literal_representation_threshold: u64 = 16384,
689    /// Whether the matches should be considered by the lint, and whether there should
690    /// be filtering for common types.
691    #[lints(manual_let_else)]
692    matches_for_let_else: MatchLintBehaviour = MatchLintBehaviour::WellKnownTypes,
693    /// The maximum number of bool parameters a function can have
694    #[lints(fn_params_excessive_bools)]
695    max_fn_params_bools: u64 = 3,
696    /// The maximum size of a file included via `include_bytes!()` or `include_str!()`, in bytes
697    #[lints(large_include_file)]
698    max_include_file_size: u64 = 1_000_000,
699    /// The maximum number of bool fields a struct can have
700    #[lints(struct_excessive_bools)]
701    max_struct_bools: u64 = 3,
702    /// When Clippy suggests using a slice pattern, this is the maximum number of elements allowed in
703    /// the slice pattern that is suggested. If more elements are necessary, the lint is suppressed.
704    /// For example, `[_, _, _, e, ..]` is a slice pattern with 4 elements.
705    #[lints(index_refutable_slice)]
706    max_suggested_slice_pattern_length: u64 = 3,
707    /// The maximum number of bounds a trait can have to be linted
708    #[lints(type_repetition_in_bounds)]
709    max_trait_bounds: u64 = 3,
710    /// Minimum chars an ident can have, anything below or equal to this will be linted.
711    #[lints(min_ident_chars)]
712    min_ident_chars_threshold: u64 = 1,
713    /// Whether to allow fields starting with an underscore to skip documentation requirements
714    #[lints(missing_docs_in_private_items)]
715    missing_docs_allow_unused: bool = false,
716    /// Whether to **only** check for missing documentation in items visible within the current
717    /// crate. For example, `pub(crate)` items.
718    #[lints(missing_docs_in_private_items)]
719    missing_docs_in_crate_items: bool = false,
720    /// The named groupings of different source item kinds within modules.
721    #[lints(arbitrary_source_item_ordering)]
722    module_item_order_groupings: SourceItemOrderingModuleItemGroupings = DEFAULT_MODULE_ITEM_ORDERING_GROUPS.into(),
723    /// Whether the items within module groups should be ordered alphabetically or not.
724    ///
725    /// This option can be configured to "all", "none", or a list of specific grouping names that should be checked
726    /// (e.g. only "enums").
727    #[lints(arbitrary_source_item_ordering)]
728    module_items_ordered_within_groupings: SourceItemOrderingWithinModuleItemGroupings =
729        SourceItemOrderingWithinModuleItemGroupings::None,
730    /// The minimum rust version that the project supports. Defaults to the `rust-version` field in `Cargo.toml`
731    #[default_text = "current version"]
732    #[lints(
733        allow_attributes,
734        allow_attributes_without_reason,
735        almost_complete_range,
736        approx_constant,
737        assigning_clones,
738        borrow_as_ptr,
739        cast_abs_to_unsigned,
740        checked_conversions,
741        cloned_instead_of_copied,
742        collapsible_match,
743        collapsible_str_replace,
744        deprecated_cfg_attr,
745        derivable_impls,
746        err_expect,
747        filter_map_next,
748        from_over_into,
749        if_then_some_else_none,
750        index_refutable_slice,
751        inefficient_to_string,
752        io_other_error,
753        iter_kv_map,
754        legacy_numeric_constants,
755        len_zero,
756        lines_filter_map_ok,
757        manual_abs_diff,
758        manual_bits,
759        manual_c_str_literals,
760        manual_clamp,
761        manual_div_ceil,
762        manual_flatten,
763        manual_hash_one,
764        manual_is_ascii_check,
765        manual_is_power_of_two,
766        manual_let_else,
767        manual_midpoint,
768        manual_non_exhaustive,
769        manual_option_as_slice,
770        manual_pattern_char_comparison,
771        manual_range_contains,
772        manual_rem_euclid,
773        manual_repeat_n,
774        manual_retain,
775        manual_slice_fill,
776        manual_slice_size_calculation,
777        manual_split_once,
778        manual_str_repeat,
779        manual_strip,
780        manual_try_fold,
781        map_clone,
782        map_unwrap_or,
783        map_with_unused_argument_over_ranges,
784        match_like_matches_macro,
785        mem_replace_option_with_some,
786        mem_replace_with_default,
787        missing_const_for_fn,
788        needless_borrow,
789        non_std_lazy_statics,
790        option_as_ref_deref,
791        or_fun_call,
792        ptr_as_ptr,
793        question_mark,
794        redundant_field_names,
795        redundant_static_lifetimes,
796        repeat_vec_with_capacity,
797        same_item_push,
798        seek_from_current,
799        to_digit_is_some,
800        transmute_ptr_to_ref,
801        tuple_array_conversions,
802        type_repetition_in_bounds,
803        unchecked_time_subtraction,
804        uninlined_format_args,
805        unnecessary_lazy_evaluations,
806        unnecessary_unwrap,
807        unnested_or_patterns,
808        unused_trait_names,
809        use_self,
810        zero_ptr,
811    )]
812    msrv: Msrv = Msrv::default(),
813    /// The minimum size (in bytes) to consider a type for passing by reference instead of by value.
814    #[lints(large_types_passed_by_value)]
815    pass_by_value_size_limit: u64 = 256,
816    /// Lint "public" fields in a struct that are prefixed with an underscore based on their
817    /// exported visibility, or whether they are marked as "pub".
818    #[lints(pub_underscore_fields)]
819    pub_underscore_fields_behavior: PubUnderscoreFieldsBehaviour = PubUnderscoreFieldsBehaviour::PubliclyExported,
820    /// Whether the type itself in a struct or enum should be replaced with `Self` when encountering recursive types.
821    #[lints(use_self)]
822    recursive_self_in_type_definitions: bool = true,
823    /// Whether to lint only if it's multiline.
824    #[lints(semicolon_inside_block)]
825    semicolon_inside_block_ignore_singleline: bool = false,
826    /// Whether to lint only if it's singleline.
827    #[lints(semicolon_outside_block)]
828    semicolon_outside_block_ignore_multiline: bool = false,
829    /// The maximum number of single char bindings a scope may have
830    #[lints(many_single_char_names)]
831    single_char_binding_names_threshold: u64 = 4,
832    /// Which kind of elements should be ordered internally, possible values being `enum`, `impl`, `module`, `struct`, `trait`.
833    #[lints(arbitrary_source_item_ordering)]
834    source_item_ordering: SourceItemOrdering = DEFAULT_SOURCE_ITEM_ORDERING.into(),
835    /// The maximum allowed stack size for functions in bytes
836    #[lints(large_stack_frames)]
837    stack_size_threshold: u64 = 512_000,
838    /// Enforce the named macros always use the braces specified.
839    ///
840    /// A `MacroMatcher` can be added like so `{ name = "macro_name", brace = "(" }`. If the macro
841    /// could be used with a full path two `MacroMatcher`s have to be added one with the full path
842    /// `crate_name::macro_name` and one with just the macro name.
843    #[lints(nonstandard_macro_braces)]
844    standard_macro_braces: Vec<MacroMatcher> = Vec::new(),
845    /// The minimum number of struct fields for the lints about field names to trigger
846    #[lints(struct_field_names)]
847    struct_field_name_threshold: u64 = 3,
848    /// Whether to suppress a restriction lint in constant code. In same
849    /// cases the restructured operation might not be unavoidable, as the
850    /// suggested counterparts are unavailable in constant code. This
851    /// configuration will cause restriction lints to trigger even
852    /// if no suggestion can be made.
853    #[lints(indexing_slicing)]
854    suppress_restriction_lint_in_const: bool = false,
855    /// The maximum size of objects (in bytes) that will be linted. Larger objects are ok on the heap
856    #[lints(boxed_local, useless_vec)]
857    too_large_for_stack: u64 = 200,
858    /// The maximum number of argument a function or method can have
859    #[lints(too_many_arguments)]
860    too_many_arguments_threshold: u64 = 7,
861    /// The maximum number of lines a function or method can have
862    #[lints(too_many_lines)]
863    too_many_lines_threshold: u64 = 100,
864    /// The order of associated items in traits.
865    #[lints(arbitrary_source_item_ordering)]
866    trait_assoc_item_kinds_order: SourceItemOrderingTraitAssocItemKinds = DEFAULT_TRAIT_ASSOC_ITEM_KINDS_ORDER.into(),
867    /// The maximum size (in bytes) to consider a `Copy` type for passing by value instead of by
868    /// reference.
869    #[default_text = "target_pointer_width"]
870    #[lints(trivially_copy_pass_by_ref)]
871    trivial_copy_size_limit: Option<u64> = None,
872    /// The maximum complexity a type can have
873    #[lints(type_complexity)]
874    type_complexity_threshold: u64 = 250,
875    /// The byte size a `T` in `Box<T>` can have, below which it triggers the `clippy::unnecessary_box` lint
876    #[lints(unnecessary_box_returns)]
877    unnecessary_box_size: u64 = 128,
878    /// Should the fraction of a decimal be linted to include separators.
879    #[lints(unreadable_literal)]
880    unreadable_literal_lint_fractions: bool = true,
881    /// Enables verbose mode. Triggers if there is more than one uppercase char next to each other
882    #[lints(upper_case_acronyms)]
883    upper_case_acronyms_aggressive: bool = false,
884    /// The size of the boxed type in bytes, where boxing in a `Vec` is allowed
885    #[lints(vec_box)]
886    vec_box_size_threshold: u64 = 4096,
887    /// The maximum allowed size of a bit mask before suggesting to use 'trailing_zeros'
888    #[lints(verbose_bit_mask)]
889    verbose_bit_mask_threshold: u64 = 1,
890    /// Whether to emit warnings on all wildcard imports, including those from `prelude`, from `super` in tests,
891    /// or for `pub use` reexports.
892    #[lints(wildcard_imports)]
893    warn_on_all_wildcard_imports: bool = false,
894    /// Whether to also emit warnings for unsafe blocks with metavariable expansions in **private** macros.
895    #[lints(macro_metavars_in_unsafe)]
896    warn_unsafe_macro_metavars_in_private_macros: bool = false,
897}
898
899/// Search for the configuration file.
900///
901/// # Errors
902///
903/// Returns any unexpected filesystem error encountered when searching for the config file
904pub fn lookup_conf_file() -> io::Result<(Option<PathBuf>, Vec<String>)> {
905    /// Possible filename to search for.
906    const CONFIG_FILE_NAMES: [&str; 2] = [".clippy.toml", "clippy.toml"];
907
908    // Start looking for a config file in CLIPPY_CONF_DIR, or failing that, CARGO_MANIFEST_DIR.
909    // If neither of those exist, use ".". (Update documentation if this priority changes)
910    let mut current = env::var_os("CLIPPY_CONF_DIR")
911        .or_else(|| env::var_os("CARGO_MANIFEST_DIR"))
912        .map_or_else(|| PathBuf::from("."), PathBuf::from)
913        .canonicalize()?;
914
915    let mut found_config: Option<PathBuf> = None;
916    let mut warnings = vec![];
917
918    loop {
919        for config_file_name in &CONFIG_FILE_NAMES {
920            if let Ok(config_file) = current.join(config_file_name).canonicalize() {
921                match fs::metadata(&config_file) {
922                    Err(e) if e.kind() == io::ErrorKind::NotFound => {},
923                    Err(e) => return Err(e),
924                    Ok(md) if md.is_dir() => {},
925                    Ok(_) => {
926                        // warn if we happen to find two config files #8323
927                        if let Some(ref found_config) = found_config {
928                            warnings.push(format!(
929                                "using config file `{}`, `{}` will be ignored",
930                                found_config.display(),
931                                config_file.display()
932                            ));
933                        } else {
934                            found_config = Some(config_file);
935                        }
936                    },
937                }
938            }
939        }
940
941        if found_config.is_some() {
942            return Ok((found_config, warnings));
943        }
944
945        // If the current directory has no parent, we're done searching.
946        if !current.pop() {
947            return Ok((None, warnings));
948        }
949    }
950}
951
952fn deserialize(file: &SourceFile) -> TryConf {
953    match toml::de::Deserializer::new(file.src.as_ref().unwrap()).deserialize_map(ConfVisitor(file)) {
954        Ok(mut conf) => {
955            extend_vec_if_indicator_present(&mut conf.conf.disallowed_names, DEFAULT_DISALLOWED_NAMES);
956            extend_vec_if_indicator_present(&mut conf.conf.allowed_prefixes, DEFAULT_ALLOWED_PREFIXES);
957            extend_vec_if_indicator_present(
958                &mut conf.conf.allow_renamed_params_for,
959                DEFAULT_ALLOWED_TRAITS_WITH_RENAMED_PARAMS,
960            );
961
962            // Confirms that the user has not accidentally configured ordering requirements for groups that
963            // aren't configured.
964            if let SourceItemOrderingWithinModuleItemGroupings::Custom(groupings) =
965                &conf.conf.module_items_ordered_within_groupings
966            {
967                for grouping in groupings {
968                    if !conf.conf.module_item_order_groupings.is_grouping(grouping) {
969                        // Since this isn't fixable by rustfix, don't emit a `Suggestion`. This just adds some useful
970                        // info for the user instead.
971
972                        let names = conf.conf.module_item_order_groupings.grouping_names();
973                        let suggestion = suggest_candidate(grouping, names.iter().map(String::as_str))
974                            .map(|s| format!(" perhaps you meant `{s}`?"))
975                            .unwrap_or_default();
976                        let names = names.iter().map(|s| format!("`{s}`")).join(", ");
977                        let message = format!(
978                            "unknown ordering group: `{grouping}` was not specified in `module-items-ordered-within-groupings`,{suggestion} expected one of: {names}"
979                        );
980
981                        let span = conf
982                            .value_spans
983                            .get("module_item_order_groupings")
984                            .cloned()
985                            .unwrap_or_default();
986                        conf.errors.push(ConfError::spanned(file, message, None, span));
987                    }
988                }
989            }
990
991            // TODO: THIS SHOULD BE TESTED, this comment will be gone soon
992            if conf.conf.allowed_idents_below_min_chars.iter().any(|e| e == "..") {
993                conf.conf
994                    .allowed_idents_below_min_chars
995                    .extend(DEFAULT_ALLOWED_IDENTS_BELOW_MIN_CHARS.iter().map(ToString::to_string));
996            }
997            if conf.conf.doc_valid_idents.iter().any(|e| e == "..") {
998                conf.conf
999                    .doc_valid_idents
1000                    .extend(DEFAULT_DOC_VALID_IDENTS.iter().map(ToString::to_string));
1001            }
1002
1003            conf
1004        },
1005        Err(e) => TryConf::from_toml_error(file, &e),
1006    }
1007}
1008
1009fn extend_vec_if_indicator_present(vec: &mut Vec<String>, default: &[&str]) {
1010    if vec.contains(&"..".to_string()) {
1011        vec.extend(default.iter().map(ToString::to_string));
1012    }
1013}
1014
1015impl Conf {
1016    pub fn read(sess: &Session, path: &io::Result<(Option<PathBuf>, Vec<String>)>) -> &'static Conf {
1017        static CONF: OnceLock<Conf> = OnceLock::new();
1018        CONF.get_or_init(|| Conf::read_inner(sess, path))
1019    }
1020
1021    fn read_inner(sess: &Session, path: &io::Result<(Option<PathBuf>, Vec<String>)>) -> Conf {
1022        match path {
1023            Ok((_, warnings)) => {
1024                for warning in warnings {
1025                    sess.dcx().warn(warning.clone());
1026                }
1027            },
1028            Err(error) => {
1029                sess.dcx()
1030                    .err(format!("error finding Clippy's configuration file: {error}"));
1031            },
1032        }
1033
1034        let TryConf {
1035            mut conf,
1036            value_spans: _,
1037            errors,
1038            warnings,
1039        } = match path {
1040            Ok((Some(path), _)) => match sess.source_map().load_file(path) {
1041                Ok(file) => deserialize(&file),
1042                Err(error) => {
1043                    sess.dcx().err(format!("failed to read `{}`: {error}", path.display()));
1044                    TryConf::default()
1045                },
1046            },
1047            _ => TryConf::default(),
1048        };
1049
1050        conf.msrv.read_cargo(sess);
1051
1052        // all conf errors are non-fatal, we just use the default conf in case of error
1053        for error in errors {
1054            let mut diag = sess.dcx().struct_span_err(
1055                error.span,
1056                format!("error reading Clippy's configuration file: {}", error.message),
1057            );
1058
1059            if let Some(sugg) = error.suggestion {
1060                diag.span_suggestion(error.span, sugg.message, sugg.suggestion, Applicability::MaybeIncorrect);
1061            }
1062
1063            diag.emit();
1064        }
1065
1066        for warning in warnings {
1067            sess.dcx().span_warn(
1068                warning.span,
1069                format!("error reading Clippy's configuration file: {}", warning.message),
1070            );
1071        }
1072
1073        conf
1074    }
1075}
1076
1077const SEPARATOR_WIDTH: usize = 4;
1078
1079#[derive(Debug)]
1080struct FieldError {
1081    error: String,
1082    suggestion: Option<Suggestion>,
1083}
1084
1085#[derive(Debug)]
1086struct Suggestion {
1087    message: &'static str,
1088    suggestion: &'static str,
1089}
1090
1091impl std::error::Error for FieldError {}
1092
1093impl Display for FieldError {
1094    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
1095        f.pad(&self.error)
1096    }
1097}
1098
1099impl serde::de::Error for FieldError {
1100    fn custom<T: Display>(msg: T) -> Self {
1101        Self {
1102            error: msg.to_string(),
1103            suggestion: None,
1104        }
1105    }
1106
1107    fn unknown_field(field: &str, expected: &'static [&'static str]) -> Self {
1108        // List the available fields sorted and at least one per line, more if `CLIPPY_TERMINAL_WIDTH` is
1109        // set and allows it.
1110        use fmt::Write;
1111
1112        let metadata = get_configuration_metadata();
1113        let deprecated = metadata
1114            .iter()
1115            .filter_map(|conf| {
1116                if conf.deprecation_reason.is_some() {
1117                    Some(conf.name.as_str())
1118                } else {
1119                    None
1120                }
1121            })
1122            .collect::<Vec<_>>();
1123
1124        let mut expected = expected
1125            .iter()
1126            .copied()
1127            .filter(|name| !deprecated.contains(name))
1128            .collect::<Vec<_>>();
1129        expected.sort_unstable();
1130
1131        let (rows, column_widths) = calculate_dimensions(&expected);
1132
1133        let mut msg = format!("unknown field `{field}`, expected one of");
1134        for row in 0..rows {
1135            writeln!(msg).unwrap();
1136            for (column, column_width) in column_widths.iter().copied().enumerate() {
1137                let index = column * rows + row;
1138                let field = expected.get(index).copied().unwrap_or_default();
1139                write!(msg, "{:SEPARATOR_WIDTH$}{field:column_width$}", " ").unwrap();
1140            }
1141        }
1142
1143        let suggestion = suggest_candidate(field, expected).map(|suggestion| Suggestion {
1144            message: "perhaps you meant",
1145            suggestion,
1146        });
1147
1148        Self { error: msg, suggestion }
1149    }
1150}
1151
1152fn calculate_dimensions(fields: &[&str]) -> (usize, Vec<usize>) {
1153    let columns = env::var("CLIPPY_TERMINAL_WIDTH")
1154        .ok()
1155        .and_then(|s| <usize as FromStr>::from_str(&s).ok())
1156        .map_or(1, |terminal_width| {
1157            let max_field_width = fields.iter().map(|field| field.len()).max().unwrap();
1158            cmp::max(1, terminal_width / (SEPARATOR_WIDTH + max_field_width))
1159        });
1160
1161    let rows = fields.len().div_ceil(columns);
1162
1163    let column_widths = (0..columns)
1164        .map(|column| {
1165            if column < columns - 1 {
1166                (0..rows)
1167                    .map(|row| {
1168                        let index = column * rows + row;
1169                        let field = fields.get(index).copied().unwrap_or_default();
1170                        field.len()
1171                    })
1172                    .max()
1173                    .unwrap()
1174            } else {
1175                // Avoid adding extra space to the last column.
1176                0
1177            }
1178        })
1179        .collect::<Vec<_>>();
1180
1181    (rows, column_widths)
1182}
1183
1184/// Given a user-provided value that couldn't be matched to a known option, finds the most likely
1185/// candidate among candidates that the user might have meant.
1186fn suggest_candidate<'a, I>(value: &str, candidates: I) -> Option<&'a str>
1187where
1188    I: IntoIterator<Item = &'a str>,
1189{
1190    candidates
1191        .into_iter()
1192        .filter_map(|expected| {
1193            let dist = edit_distance(value, expected, 4)?;
1194            Some((dist, expected))
1195        })
1196        .min_by_key(|&(dist, _)| dist)
1197        .map(|(_, suggestion)| suggestion)
1198}
1199
1200#[cfg(test)]
1201mod tests {
1202    use serde::de::IgnoredAny;
1203    use std::collections::{HashMap, HashSet};
1204    use std::fs;
1205    use walkdir::WalkDir;
1206
1207    #[test]
1208    fn configs_are_tested() {
1209        let mut names: HashSet<String> = crate::get_configuration_metadata()
1210            .into_iter()
1211            .filter_map(|meta| {
1212                if meta.deprecation_reason.is_none() {
1213                    Some(meta.name.replace('_', "-"))
1214                } else {
1215                    None
1216                }
1217            })
1218            .collect();
1219
1220        let toml_files = WalkDir::new("../tests")
1221            .into_iter()
1222            .map(Result::unwrap)
1223            .filter(|entry| entry.file_name() == "clippy.toml");
1224
1225        for entry in toml_files {
1226            let file = fs::read_to_string(entry.path()).unwrap();
1227            #[expect(clippy::zero_sized_map_values)]
1228            if let Ok(map) = toml::from_str::<HashMap<String, IgnoredAny>>(&file) {
1229                for name in map.keys() {
1230                    names.remove(name.as_str());
1231                }
1232            }
1233        }
1234
1235        assert!(
1236            names.is_empty(),
1237            "Configuration variable lacks test: {names:?}\nAdd a test to `tests/ui-toml`"
1238        );
1239    }
1240}
clippy_config/conf.rs

clippy_config/
conf.rs
