1 // Copyright 2017 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
13 use errors::DiagnosticBuilder;
15 use ich::StableHashingContext;
17 use lint::context::CheckLintNameResult;
18 use lint::{self, Lint, LintId, Level, LintSource};
19 use rustc_data_structures::stable_hasher::{HashStable, ToStableHashKey,
20 StableHasher, StableHasherResult};
24 use syntax::codemap::MultiSpan;
25 use syntax::symbol::Symbol;
26 use util::nodemap::FxHashMap;
28 pub struct LintLevelSets {
35 // -A,-W,-D flags, a `Symbol` for the flag itself and `Level` for which
37 specs: FxHashMap<LintId, (Level, LintSource)>,
41 specs: FxHashMap<LintId, (Level, LintSource)>,
47 pub fn new(sess: &Session) -> LintLevelSets {
48 let mut me = LintLevelSets {
50 lint_cap: Level::Forbid,
52 me.process_command_line(sess);
56 pub fn builder(sess: &Session) -> LintLevelsBuilder {
57 LintLevelsBuilder::new(sess, LintLevelSets::new(sess))
60 fn process_command_line(&mut self, sess: &Session) {
61 let store = sess.lint_store.borrow();
62 let mut specs = FxHashMap();
63 self.lint_cap = sess.opts.lint_cap.unwrap_or(Level::Forbid);
65 for &(ref lint_name, level) in &sess.opts.lint_opts {
66 store.check_lint_name_cmdline(sess, &lint_name, level);
68 // If the cap is less than this specified level, e.g. if we've got
69 // `--cap-lints allow` but we've also got `-D foo` then we ignore
70 // this specification as the lint cap will set it to allow anyway.
71 let level = cmp::min(level, self.lint_cap);
73 let lint_flag_val = Symbol::intern(lint_name);
74 let ids = match store.find_lints(&lint_name) {
76 Err(_) => continue, // errors handled in check_lint_name_cmdline above
79 let src = LintSource::CommandLine(lint_flag_val);
80 specs.insert(id, (level, src));
84 self.list.push(LintSet::CommandLine {
89 fn get_lint_level(&self,
92 aux: Option<&FxHashMap<LintId, (Level, LintSource)>>,
94 -> (Level, LintSource)
96 let (level, mut src) = self.get_lint_id_level(LintId::of(lint), idx, aux);
98 // If `level` is none then we actually assume the default level for this
100 let mut level = level.unwrap_or(lint.default_level(sess));
102 // If we're about to issue a warning, check at the last minute for any
103 // directives against the warnings "lint". If, for example, there's an
104 // `allow(warnings)` in scope then we want to respect that instead.
105 if level == Level::Warn {
106 let (warnings_level, warnings_src) =
107 self.get_lint_id_level(LintId::of(lint::builtin::WARNINGS),
110 if let Some(configured_warning_level) = warnings_level {
111 if configured_warning_level != Level::Warn {
112 level = configured_warning_level;
118 // Ensure that we never exceed the `--cap-lints` argument.
119 level = cmp::min(level, self.lint_cap);
124 fn get_lint_id_level(&self,
127 aux: Option<&FxHashMap<LintId, (Level, LintSource)>>)
128 -> (Option<Level>, LintSource)
130 if let Some(specs) = aux {
131 if let Some(&(level, src)) = specs.get(&id) {
132 return (Some(level), src)
136 match self.list[idx as usize] {
137 LintSet::CommandLine { ref specs } => {
138 if let Some(&(level, src)) = specs.get(&id) {
139 return (Some(level), src)
141 return (None, LintSource::Default)
143 LintSet::Node { ref specs, parent } => {
144 if let Some(&(level, src)) = specs.get(&id) {
145 return (Some(level), src)
154 pub struct LintLevelsBuilder<'a> {
157 id_to_set: FxHashMap<HirId, u32>,
159 warn_about_weird_lints: bool,
162 pub struct BuilderPush {
166 impl<'a> LintLevelsBuilder<'a> {
167 pub fn new(sess: &'a Session, sets: LintLevelSets) -> LintLevelsBuilder<'a> {
168 assert_eq!(sets.list.len(), 1);
173 id_to_set: FxHashMap(),
174 warn_about_weird_lints: sess.buffered_lints.borrow().is_some(),
178 /// Pushes a list of AST lint attributes onto this context.
180 /// This function will return a `BuilderPush` object which should be be
181 /// passed to `pop` when this scope for the attributes provided is exited.
183 /// This function will perform a number of tasks:
185 /// * It'll validate all lint-related attributes in `attrs`
186 /// * It'll mark all lint-related attriutes as used
187 /// * Lint levels will be updated based on the attributes provided
188 /// * Lint attributes are validated, e.g. a #[forbid] can't be switched to
191 /// Don't forget to call `pop`!
192 pub fn push(&mut self, attrs: &[ast::Attribute]) -> BuilderPush {
193 let mut specs = FxHashMap();
194 let store = self.sess.lint_store.borrow();
195 let sess = self.sess;
196 let bad_attr = |span| {
197 span_err!(sess, span, E0452,
198 "malformed lint attribute");
201 let level = match Level::from_str(&attr.name().as_str()) {
206 let meta = unwrap_or!(attr.meta(), continue);
207 attr::mark_used(attr);
209 let metas = if let Some(metas) = meta.meta_item_list() {
217 let word = match li.word() {
224 let name = word.name();
225 match store.check_lint_name(&name.as_str()) {
226 CheckLintNameResult::Ok(ids) => {
227 let src = LintSource::Node(name, li.span);
229 specs.insert(*id, (level, src));
233 _ if !self.warn_about_weird_lints => {}
235 CheckLintNameResult::Warning(ref msg) => {
236 let lint = builtin::RENAMED_AND_REMOVED_LINTS;
237 let (level, src) = self.sets.get_lint_level(lint,
241 lint::struct_lint_level(self.sess,
245 Some(li.span.into()),
249 CheckLintNameResult::NoLint => {
250 let lint = builtin::UNKNOWN_LINTS;
251 let (level, src) = self.sets.get_lint_level(lint,
255 let msg = format!("unknown lint: `{}`", name);
256 let mut db = lint::struct_lint_level(self.sess,
260 Some(li.span.into()),
262 if name.as_str().chars().any(|c| c.is_uppercase()) {
263 let name_lower = name.as_str().to_lowercase().to_string();
264 if let CheckLintNameResult::NoLint =
265 store.check_lint_name(&name_lower) {
270 "lowercase the lint name",
282 for (id, &(level, ref src)) in specs.iter() {
283 if level == Level::Forbid {
286 let forbid_src = match self.sets.get_lint_id_level(*id, self.cur, None) {
287 (Some(Level::Forbid), src) => src,
290 let forbidden_lint_name = match forbid_src {
291 LintSource::Default => id.to_string(),
292 LintSource::Node(name, _) => name.to_string(),
293 LintSource::CommandLine(name) => name.to_string(),
295 let (lint_attr_name, lint_attr_span) = match *src {
296 LintSource::Node(name, span) => (name, span),
299 let mut diag_builder = struct_span_err!(self.sess,
302 "{}({}) overruled by outer forbid({})",
305 forbidden_lint_name);
306 diag_builder.span_label(lint_attr_span, "overruled by previous forbid");
308 LintSource::Default => &mut diag_builder,
309 LintSource::Node(_, forbid_source_span) => {
310 diag_builder.span_label(forbid_source_span,
311 "`forbid` level set here")
313 LintSource::CommandLine(_) => {
314 diag_builder.note("`forbid` lint level was set on command line")
317 // don't set a separate error for every lint in the group
323 self.cur = self.sets.list.len() as u32;
324 self.sets.list.push(LintSet::Node {
335 /// Called after `push` when the scope of a set of attributes are exited.
336 pub fn pop(&mut self, push: BuilderPush) {
337 self.cur = push.prev;
340 /// Used to emit a lint-related diagnostic based on the current state of
341 /// this lint context.
342 pub fn struct_lint(&self,
344 span: Option<MultiSpan>,
346 -> DiagnosticBuilder<'a>
348 let (level, src) = self.sets.get_lint_level(lint, self.cur, None, self.sess);
349 lint::struct_lint_level(self.sess, lint, level, src, span, msg)
352 /// Registers the ID provided with the current set of lints stored in
354 pub fn register_id(&mut self, id: HirId) {
355 self.id_to_set.insert(id, self.cur);
358 pub fn build(self) -> LintLevelSets {
362 pub fn build_map(self) -> LintLevelMap {
365 id_to_set: self.id_to_set,
370 pub struct LintLevelMap {
372 id_to_set: FxHashMap<HirId, u32>,
376 /// If the `id` was previously registered with `register_id` when building
377 /// this `LintLevelMap` this returns the corresponding lint level and source
378 /// of the lint level for the lint provided.
380 /// If the `id` was not previously registered, returns `None`. If `None` is
381 /// returned then the parent of `id` should be acquired and this function
382 /// should be called again.
383 pub fn level_and_source(&self, lint: &'static Lint, id: HirId, session: &Session)
384 -> Option<(Level, LintSource)>
386 self.id_to_set.get(&id).map(|idx| {
387 self.sets.get_lint_level(lint, *idx, None, session)
391 /// Returns if this `id` has lint level information.
392 pub fn lint_level_set(&self, id: HirId) -> Option<u32> {
393 self.id_to_set.get(&id).cloned()
397 impl<'a> HashStable<StableHashingContext<'a>> for LintLevelMap {
399 fn hash_stable<W: StableHasherResult>(&self,
400 hcx: &mut StableHashingContext<'a>,
401 hasher: &mut StableHasher<W>) {
407 id_to_set.hash_stable(hcx, hasher);
414 lint_cap.hash_stable(hcx, hasher);
416 hcx.while_hashing_spans(true, |hcx| {
417 list.len().hash_stable(hcx, hasher);
419 // We are working under the assumption here that the list of
420 // lint-sets is built in a deterministic order.
421 for lint_set in list {
422 ::std::mem::discriminant(lint_set).hash_stable(hcx, hasher);
425 LintSet::CommandLine { ref specs } => {
426 specs.hash_stable(hcx, hasher);
428 LintSet::Node { ref specs, parent } => {
429 specs.hash_stable(hcx, hasher);
430 parent.hash_stable(hcx, hasher);
438 impl<HCX> HashStable<HCX> for LintId {
440 fn hash_stable<W: StableHasherResult>(&self,
442 hasher: &mut StableHasher<W>) {
443 self.lint_name_raw().hash_stable(hcx, hasher);
447 impl<HCX> ToStableHashKey<HCX> for LintId {
448 type KeyType = &'static str;
451 fn to_stable_hash_key(&self, _: &HCX) -> &'static str {