clippy_lints/src/utils/internal_lints.rs

   1 use crate::utils::SpanlessEq;
   2 use crate::utils::{
   3     is_expn_of, match_def_path, match_qpath, match_type, method_calls, paths, snippet, span_lint, span_lint_and_help,
   4     span_lint_and_sugg, walk_ptrs_ty,
   5 };
   6 use if_chain::if_chain;
   7 use rustc_ast::ast::{Crate as AstCrate, ItemKind, LitKind, Name, NodeId};
   8 use rustc_ast::visit::FnKind;
   9 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
  10 use rustc_errors::Applicability;
  11 use rustc_hir as hir;
  12 use rustc_hir::def::{DefKind, Res};
  13 use rustc_hir::intravisit::{walk_expr, NestedVisitorMap, Visitor};
  14 use rustc_hir::{Crate, Expr, ExprKind, HirId, Item, MutTy, Mutability, Path, StmtKind, Ty, TyKind};
  15 use rustc_lint::{EarlyContext, EarlyLintPass, LateContext, LateLintPass};
  16 use rustc_middle::hir::map::Map;
  17 use rustc_session::{declare_lint_pass, declare_tool_lint, impl_lint_pass};
  18 use rustc_span::source_map::{Span, Spanned};
  19 use rustc_span::symbol::SymbolStr;
  20
  21 use std::borrow::{Borrow, Cow};
  22
  23 declare_clippy_lint! {
  24     /// **What it does:** Checks for various things we like to keep tidy in clippy.
  25     ///
  26     /// **Why is this bad?** We like to pretend we're an example of tidy code.
  27     ///
  28     /// **Known problems:** None.
  29     ///
  30     /// **Example:** Wrong ordering of the util::paths constants.
  31     pub CLIPPY_LINTS_INTERNAL,
  32     internal,
  33     "various things that will negatively affect your clippy experience"
  34 }
  35
  36 declare_clippy_lint! {
  37     /// **What it does:** Ensures every lint is associated to a `LintPass`.
  38     ///
  39     /// **Why is this bad?** The compiler only knows lints via a `LintPass`. Without
  40     /// putting a lint to a `LintPass::get_lints()`'s return, the compiler will not
  41     /// know the name of the lint.
  42     ///
  43     /// **Known problems:** Only checks for lints associated using the
  44     /// `declare_lint_pass!`, `impl_lint_pass!`, and `lint_array!` macros.
  45     ///
  46     /// **Example:**
  47     /// ```rust,ignore
  48     /// declare_lint! { pub LINT_1, ... }
  49     /// declare_lint! { pub LINT_2, ... }
  50     /// declare_lint! { pub FORGOTTEN_LINT, ... }
  51     /// // ...
  52     /// declare_lint_pass!(Pass => [LINT_1, LINT_2]);
  53     /// // missing FORGOTTEN_LINT
  54     /// ```
  55     pub LINT_WITHOUT_LINT_PASS,
  56     internal,
  57     "declaring a lint without associating it in a LintPass"
  58 }
  59
  60 declare_clippy_lint! {
  61     /// **What it does:** Checks for calls to `cx.span_lint*` and suggests to use the `utils::*`
  62     /// variant of the function.
  63     ///
  64     /// **Why is this bad?** The `utils::*` variants also add a link to the Clippy documentation to the
  65     /// warning/error messages.
  66     ///
  67     /// **Known problems:** None.
  68     ///
  69     /// **Example:**
  70     /// Bad:
  71     /// ```rust,ignore
  72     /// cx.span_lint(LINT_NAME, "message");
  73     /// ```
  74     ///
  75     /// Good:
  76     /// ```rust,ignore
  77     /// utils::span_lint(cx, LINT_NAME, "message");
  78     /// ```
  79     pub COMPILER_LINT_FUNCTIONS,
  80     internal,
  81     "usage of the lint functions of the compiler instead of the utils::* variant"
  82 }
  83
  84 declare_clippy_lint! {
  85     /// **What it does:** Checks for calls to `cx.outer().expn_data()` and suggests to use
  86     /// the `cx.outer_expn_data()`
  87     ///
  88     /// **Why is this bad?** `cx.outer_expn_data()` is faster and more concise.
  89     ///
  90     /// **Known problems:** None.
  91     ///
  92     /// **Example:**
  93     /// Bad:
  94     /// ```rust,ignore
  95     /// expr.span.ctxt().outer().expn_data()
  96     /// ```
  97     ///
  98     /// Good:
  99     /// ```rust,ignore
 100     /// expr.span.ctxt().outer_expn_data()
 101     /// ```
 102     pub OUTER_EXPN_EXPN_DATA,
 103     internal,
 104     "using `cx.outer_expn().expn_data()` instead of `cx.outer_expn_data()`"
 105 }
 106
 107 declare_clippy_lint! {
 108     /// **What it does:** Not an actual lint. This lint is only meant for testing our customized internal compiler
 109     /// error message by calling `panic`.
 110     ///
 111     /// **Why is this bad?** ICE in large quantities can damage your teeth
 112     ///
 113     /// **Known problems:** None
 114     ///
 115     /// **Example:**
 116     /// Bad:
 117     /// ```rust,ignore
 118     /// 🍦🍦🍦🍦🍦
 119     /// ```
 120     pub PRODUCE_ICE,
 121     internal,
 122     "this message should not appear anywhere as we ICE before and don't emit the lint"
 123 }
 124
 125 declare_clippy_lint! {
 126     /// **What it does:** Checks for cases of an auto-generated lint without an updated description,
 127     /// i.e. `default lint description`.
 128     ///
 129     /// **Why is this bad?** Indicates that the lint is not finished.
 130     ///
 131     /// **Known problems:** None
 132     ///
 133     /// **Example:**
 134     /// Bad:
 135     /// ```rust,ignore
 136     /// declare_lint! { pub COOL_LINT, nursery, "default lint description" }
 137     /// ```
 138     ///
 139     /// Good:
 140     /// ```rust,ignore
 141     /// declare_lint! { pub COOL_LINT, nursery, "a great new lint" }
 142     /// ```
 143     pub DEFAULT_LINT,
 144     internal,
 145     "found 'default lint description' in a lint declaration"
 146 }
 147
 148 declare_clippy_lint! {
 149     /// **What it does:** Lints `span_lint_and_then` function calls, where the
 150     /// closure argument has only one statement and that statement is a method
 151     /// call to `span_suggestion`, `span_help`, `span_note` (using the same
 152     /// span), `help` or `note`.
 153     ///
 154     /// These usages of `span_lint_and_then` should be replaced with one of the
 155     /// wrapper functions `span_lint_and_sugg`, span_lint_and_help`, or
 156     /// `span_lint_and_note`.
 157     ///
 158     /// **Why is this bad?** Using the wrapper `span_lint_and_*` functions, is more
 159     /// convenient, readable and less error prone.
 160     ///
 161     /// **Known problems:** None
 162     ///
 163     /// *Example:**
 164     /// Bad:
 165     /// ```rust,ignore
 166     /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
 167     ///     diag.span_suggestion(
 168     ///         expr.span,
 169     ///         help_msg,
 170     ///         sugg.to_string(),
 171     ///         Applicability::MachineApplicable,
 172     ///     );
 173     /// });
 174     /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
 175     ///     diag.span_help(expr.span, help_msg);
 176     /// });
 177     /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
 178     ///     diag.help(help_msg);
 179     /// });
 180     /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
 181     ///     diag.span_note(expr.span, note_msg);
 182     /// });
 183     /// span_lint_and_then(cx, TEST_LINT, expr.span, lint_msg, |diag| {
 184     ///     diag.note(note_msg);
 185     /// });
 186     /// ```
 187     ///
 188     /// Good:
 189     /// ```rust,ignore
 190     /// span_lint_and_sugg(
 191     ///     cx,
 192     ///     TEST_LINT,
 193     ///     expr.span,
 194     ///     lint_msg,
 195     ///     help_msg,
 196     ///     sugg.to_string(),
 197     ///     Applicability::MachineApplicable,
 198     /// );
 199     /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), help_msg);
 200     /// span_lint_and_help(cx, TEST_LINT, expr.span, lint_msg, None, help_msg);
 201     /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, Some(expr.span), note_msg);
 202     /// span_lint_and_note(cx, TEST_LINT, expr.span, lint_msg, None, note_msg);
 203     /// ```
 204     pub COLLAPSIBLE_SPAN_LINT_CALLS,
 205     internal,
 206     "found collapsible `span_lint_and_then` calls"
 207 }
 208
 209 declare_lint_pass!(ClippyLintsInternal => [CLIPPY_LINTS_INTERNAL]);
 210
 211 impl EarlyLintPass for ClippyLintsInternal {
 212     fn check_crate(&mut self, cx: &EarlyContext<'_>, krate: &AstCrate) {
 213         if let Some(utils) = krate
 214             .module
 215             .items
 216             .iter()
 217             .find(|item| item.ident.name.as_str() == "utils")
 218         {
 219             if let ItemKind::Mod(ref utils_mod) = utils.kind {
 220                 if let Some(paths) = utils_mod.items.iter().find(|item| item.ident.name.as_str() == "paths") {
 221                     if let ItemKind::Mod(ref paths_mod) = paths.kind {
 222                         let mut last_name: Option<SymbolStr> = None;
 223                         for item in &*paths_mod.items {
 224                             let name = item.ident.as_str();
 225                             if let Some(ref last_name) = last_name {
 226                                 if **last_name > *name {
 227                                     span_lint(
 228                                         cx,
 229                                         CLIPPY_LINTS_INTERNAL,
 230                                         item.span,
 231                                         "this constant should be before the previous constant due to lexical \
 232                                          ordering",
 233                                     );
 234                                 }
 235                             }
 236                             last_name = Some(name);
 237                         }
 238                     }
 239                 }
 240             }
 241         }
 242     }
 243 }
 244
 245 #[derive(Clone, Debug, Default)]
 246 pub struct LintWithoutLintPass {
 247     declared_lints: FxHashMap<Name, Span>,
 248     registered_lints: FxHashSet<Name>,
 249 }
 250
 251 impl_lint_pass!(LintWithoutLintPass => [DEFAULT_LINT, LINT_WITHOUT_LINT_PASS]);
 252
 253 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for LintWithoutLintPass {
 254     fn check_item(&mut self, cx: &LateContext<'a, 'tcx>, item: &'tcx Item<'_>) {
 255         if let hir::ItemKind::Static(ref ty, Mutability::Not, body_id) = item.kind {
 256             if is_lint_ref_type(cx, ty) {
 257                 let expr = &cx.tcx.hir().body(body_id).value;
 258                 if_chain! {
 259                     if let ExprKind::AddrOf(_, _, ref inner_exp) = expr.kind;
 260                     if let ExprKind::Struct(_, ref fields, _) = inner_exp.kind;
 261                     let field = fields
 262                         .iter()
 263                         .find(|f| f.ident.as_str() == "desc")
 264                         .expect("lints must have a description field");
 265                     if let ExprKind::Lit(Spanned {
 266                         node: LitKind::Str(ref sym, _),
 267                         ..
 268                     }) = field.expr.kind;
 269                     if sym.as_str() == "default lint description";
 270
 271                     then {
 272                         span_lint(
 273                             cx,
 274                             DEFAULT_LINT,
 275                             item.span,
 276                             &format!("the lint `{}` has the default lint description", item.ident.name),
 277                         );
 278                     }
 279                 }
 280                 self.declared_lints.insert(item.ident.name, item.span);
 281             }
 282         } else if is_expn_of(item.span, "impl_lint_pass").is_some()
 283             || is_expn_of(item.span, "declare_lint_pass").is_some()
 284         {
 285             if let hir::ItemKind::Impl {
 286                 of_trait: None,
 287                 items: ref impl_item_refs,
 288                 ..
 289             } = item.kind
 290             {
 291                 let mut collector = LintCollector {
 292                     output: &mut self.registered_lints,
 293                     cx,
 294                 };
 295                 let body_id = cx.tcx.hir().body_owned_by(
 296                     impl_item_refs
 297                         .iter()
 298                         .find(|iiref| iiref.ident.as_str() == "get_lints")
 299                         .expect("LintPass needs to implement get_lints")
 300                         .id
 301                         .hir_id,
 302                 );
 303                 collector.visit_expr(&cx.tcx.hir().body(body_id).value);
 304             }
 305         }
 306     }
 307
 308     fn check_crate_post(&mut self, cx: &LateContext<'a, 'tcx>, _: &'tcx Crate<'_>) {
 309         for (lint_name, &lint_span) in &self.declared_lints {
 310             // When using the `declare_tool_lint!` macro, the original `lint_span`'s
 311             // file points to "<rustc macros>".
 312             // `compiletest-rs` thinks that's an error in a different file and
 313             // just ignores it. This causes the test in compile-fail/lint_pass
 314             // not able to capture the error.
 315             // Therefore, we need to climb the macro expansion tree and find the
 316             // actual span that invoked `declare_tool_lint!`:
 317             let lint_span = lint_span.ctxt().outer_expn_data().call_site;
 318
 319             if !self.registered_lints.contains(lint_name) {
 320                 span_lint(
 321                     cx,
 322                     LINT_WITHOUT_LINT_PASS,
 323                     lint_span,
 324                     &format!("the lint `{}` is not added to any `LintPass`", lint_name),
 325                 );
 326             }
 327         }
 328     }
 329 }
 330
 331 fn is_lint_ref_type<'tcx>(cx: &LateContext<'_, 'tcx>, ty: &Ty<'_>) -> bool {
 332     if let TyKind::Rptr(
 333         _,
 334         MutTy {
 335             ty: ref inner,
 336             mutbl: Mutability::Not,
 337         },
 338     ) = ty.kind
 339     {
 340         if let TyKind::Path(ref path) = inner.kind {
 341             if let Res::Def(DefKind::Struct, def_id) = cx.tables.qpath_res(path, inner.hir_id) {
 342                 return match_def_path(cx, def_id, &paths::LINT);
 343             }
 344         }
 345     }
 346
 347     false
 348 }
 349
 350 struct LintCollector<'a, 'tcx> {
 351     output: &'a mut FxHashSet<Name>,
 352     cx: &'a LateContext<'a, 'tcx>,
 353 }
 354
 355 impl<'a, 'tcx> Visitor<'tcx> for LintCollector<'a, 'tcx> {
 356     type Map = Map<'tcx>;
 357
 358     fn visit_expr(&mut self, expr: &'tcx Expr<'_>) {
 359         walk_expr(self, expr);
 360     }
 361
 362     fn visit_path(&mut self, path: &'tcx Path<'_>, _: HirId) {
 363         if path.segments.len() == 1 {
 364             self.output.insert(path.segments[0].ident.name);
 365         }
 366     }
 367     fn nested_visit_map(&mut self) -> NestedVisitorMap<Self::Map> {
 368         NestedVisitorMap::All(self.cx.tcx.hir())
 369     }
 370 }
 371
 372 #[derive(Clone, Default)]
 373 pub struct CompilerLintFunctions {
 374     map: FxHashMap<&'static str, &'static str>,
 375 }
 376
 377 impl CompilerLintFunctions {
 378     #[must_use]
 379     pub fn new() -> Self {
 380         let mut map = FxHashMap::default();
 381         map.insert("span_lint", "utils::span_lint");
 382         map.insert("struct_span_lint", "utils::span_lint");
 383         map.insert("lint", "utils::span_lint");
 384         map.insert("span_lint_note", "utils::span_lint_and_note");
 385         map.insert("span_lint_help", "utils::span_lint_and_help");
 386         Self { map }
 387     }
 388 }
 389
 390 impl_lint_pass!(CompilerLintFunctions => [COMPILER_LINT_FUNCTIONS]);
 391
 392 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for CompilerLintFunctions {
 393     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
 394         if_chain! {
 395             if let ExprKind::MethodCall(ref path, _, ref args) = expr.kind;
 396             let fn_name = path.ident;
 397             if let Some(sugg) = self.map.get(&*fn_name.as_str());
 398             let ty = walk_ptrs_ty(cx.tables.expr_ty(&args[0]));
 399             if match_type(cx, ty, &paths::EARLY_CONTEXT)
 400                 || match_type(cx, ty, &paths::LATE_CONTEXT);
 401             then {
 402                 span_lint_and_help(
 403                     cx,
 404                     COMPILER_LINT_FUNCTIONS,
 405                     path.ident.span,
 406                     "usage of a compiler lint function",
 407                     None,
 408                     &format!("please use the Clippy variant of this function: `{}`", sugg),
 409                 );
 410             }
 411         }
 412     }
 413 }
 414
 415 declare_lint_pass!(OuterExpnDataPass => [OUTER_EXPN_EXPN_DATA]);
 416
 417 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for OuterExpnDataPass {
 418     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr<'_>) {
 419         let (method_names, arg_lists, spans) = method_calls(expr, 2);
 420         let method_names: Vec<SymbolStr> = method_names.iter().map(|s| s.as_str()).collect();
 421         let method_names: Vec<&str> = method_names.iter().map(|s| &**s).collect();
 422         if_chain! {
 423             if let ["expn_data", "outer_expn"] = method_names.as_slice();
 424             let args = arg_lists[1];
 425             if args.len() == 1;
 426             let self_arg = &args[0];
 427             let self_ty = walk_ptrs_ty(cx.tables.expr_ty(self_arg));
 428             if match_type(cx, self_ty, &paths::SYNTAX_CONTEXT);
 429             then {
 430                 span_lint_and_sugg(
 431                     cx,
 432                     OUTER_EXPN_EXPN_DATA,
 433                     spans[1].with_hi(expr.span.hi()),
 434                     "usage of `outer_expn().expn_data()`",
 435                     "try",
 436                     "outer_expn_data()".to_string(),
 437                     Applicability::MachineApplicable,
 438                 );
 439             }
 440         }
 441     }
 442 }
 443
 444 declare_lint_pass!(ProduceIce => [PRODUCE_ICE]);
 445
 446 impl EarlyLintPass for ProduceIce {
 447     fn check_fn(&mut self, _: &EarlyContext<'_>, fn_kind: FnKind<'_>, _: Span, _: NodeId) {
 448         if is_trigger_fn(fn_kind) {
 449             panic!("Would you like some help with that?");
 450         }
 451     }
 452 }
 453
 454 fn is_trigger_fn(fn_kind: FnKind<'_>) -> bool {
 455     match fn_kind {
 456         FnKind::Fn(_, ident, ..) => ident.name.as_str() == "it_looks_like_you_are_trying_to_kill_clippy",
 457         FnKind::Closure(..) => false,
 458     }
 459 }
 460
 461 declare_lint_pass!(CollapsibleCalls => [COLLAPSIBLE_SPAN_LINT_CALLS]);
 462
 463 impl<'a, 'tcx> LateLintPass<'a, 'tcx> for CollapsibleCalls {
 464     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx hir::Expr<'_>) {
 465         if_chain! {
 466             if let ExprKind::Call(ref func, ref and_then_args) = expr.kind;
 467             if let ExprKind::Path(ref path) = func.kind;
 468             if match_qpath(path, &["span_lint_and_then"]);
 469             if and_then_args.len() == 5;
 470             if let ExprKind::Closure(_, _, body_id, _, _) = &and_then_args[4].kind;
 471             let body = cx.tcx.hir().body(*body_id);
 472             if let ExprKind::Block(block, _) = &body.value.kind;
 473             let stmts = &block.stmts;
 474             if stmts.len() == 1 && block.expr.is_none();
 475             if let StmtKind::Semi(only_expr) = &stmts[0].kind;
 476             if let ExprKind::MethodCall(ref ps, _, ref span_call_args) = &only_expr.kind;
 477             let and_then_snippets = get_and_then_snippets(cx, and_then_args);
 478             let mut sle = SpanlessEq::new(cx).ignore_fn();
 479             then {
 480                 match &*ps.ident.as_str() {
 481                     "span_suggestion" if sle.eq_expr(&and_then_args[2], &span_call_args[1]) => {
 482                         suggest_suggestion(cx, expr, &and_then_snippets, &span_suggestion_snippets(cx, span_call_args));
 483                     },
 484                     "span_help" if sle.eq_expr(&and_then_args[2], &span_call_args[1]) => {
 485                         let help_snippet = snippet(cx, span_call_args[2].span, r#""...""#);
 486                         suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), true);
 487                     },
 488                     "span_note" if sle.eq_expr(&and_then_args[2], &span_call_args[1]) => {
 489                         let note_snippet = snippet(cx, span_call_args[2].span, r#""...""#);
 490                         suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), true);
 491                     },
 492                     "help" => {
 493                         let help_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
 494                         suggest_help(cx, expr, &and_then_snippets, help_snippet.borrow(), false);
 495                     }
 496                     "note" => {
 497                         let note_snippet = snippet(cx, span_call_args[1].span, r#""...""#);
 498                         suggest_note(cx, expr, &and_then_snippets, note_snippet.borrow(), false);
 499                     }
 500                     _  => (),
 501                 }
 502             }
 503         }
 504     }
 505 }
 506
 507 struct AndThenSnippets<'a> {
 508     cx: Cow<'a, str>,
 509     lint: Cow<'a, str>,
 510     span: Cow<'a, str>,
 511     msg: Cow<'a, str>,
 512 }
 513
 514 fn get_and_then_snippets<'a, 'hir>(
 515     cx: &LateContext<'_, '_>,
 516     and_then_snippets: &'hir [Expr<'hir>],
 517 ) -> AndThenSnippets<'a> {
 518     let cx_snippet = snippet(cx, and_then_snippets[0].span, "cx");
 519     let lint_snippet = snippet(cx, and_then_snippets[1].span, "..");
 520     let span_snippet = snippet(cx, and_then_snippets[2].span, "span");
 521     let msg_snippet = snippet(cx, and_then_snippets[3].span, r#""...""#);
 522
 523     AndThenSnippets {
 524         cx: cx_snippet,
 525         lint: lint_snippet,
 526         span: span_snippet,
 527         msg: msg_snippet,
 528     }
 529 }
 530
 531 struct SpanSuggestionSnippets<'a> {
 532     help: Cow<'a, str>,
 533     sugg: Cow<'a, str>,
 534     applicability: Cow<'a, str>,
 535 }
 536
 537 fn span_suggestion_snippets<'a, 'hir>(
 538     cx: &LateContext<'_, '_>,
 539     span_call_args: &'hir [Expr<'hir>],
 540 ) -> SpanSuggestionSnippets<'a> {
 541     let help_snippet = snippet(cx, span_call_args[2].span, r#""...""#);
 542     let sugg_snippet = snippet(cx, span_call_args[3].span, "..");
 543     let applicability_snippet = snippet(cx, span_call_args[4].span, "Applicability::MachineApplicable");
 544
 545     SpanSuggestionSnippets {
 546         help: help_snippet,
 547         sugg: sugg_snippet,
 548         applicability: applicability_snippet,
 549     }
 550 }
 551
 552 fn suggest_suggestion(
 553     cx: &LateContext<'_, '_>,
 554     expr: &Expr<'_>,
 555     and_then_snippets: &AndThenSnippets<'_>,
 556     span_suggestion_snippets: &SpanSuggestionSnippets<'_>,
 557 ) {
 558     span_lint_and_sugg(
 559         cx,
 560         COLLAPSIBLE_SPAN_LINT_CALLS,
 561         expr.span,
 562         "this call is collapsible",
 563         "collapse into",
 564         format!(
 565             "span_lint_and_sugg({}, {}, {}, {}, {}, {}, {})",
 566             and_then_snippets.cx,
 567             and_then_snippets.lint,
 568             and_then_snippets.span,
 569             and_then_snippets.msg,
 570             span_suggestion_snippets.help,
 571             span_suggestion_snippets.sugg,
 572             span_suggestion_snippets.applicability
 573         ),
 574         Applicability::MachineApplicable,
 575     );
 576 }
 577
 578 fn suggest_help(
 579     cx: &LateContext<'_, '_>,
 580     expr: &Expr<'_>,
 581     and_then_snippets: &AndThenSnippets<'_>,
 582     help: &str,
 583     with_span: bool,
 584 ) {
 585     let option_span = if with_span {
 586         format!("Some({})", and_then_snippets.span)
 587     } else {
 588         "None".to_string()
 589     };
 590
 591     span_lint_and_sugg(
 592         cx,
 593         COLLAPSIBLE_SPAN_LINT_CALLS,
 594         expr.span,
 595         "this call is collapsible",
 596         "collapse into",
 597         format!(
 598             "span_lint_and_help({}, {}, {}, {}, {}, {})",
 599             and_then_snippets.cx,
 600             and_then_snippets.lint,
 601             and_then_snippets.span,
 602             and_then_snippets.msg,
 603             &option_span,
 604             help
 605         ),
 606         Applicability::MachineApplicable,
 607     );
 608 }
 609
 610 fn suggest_note(
 611     cx: &LateContext<'_, '_>,
 612     expr: &Expr<'_>,
 613     and_then_snippets: &AndThenSnippets<'_>,
 614     note: &str,
 615     with_span: bool,
 616 ) {
 617     let note_span = if with_span {
 618         format!("Some({})", and_then_snippets.span)
 619     } else {
 620         "None".to_string()
 621     };
 622
 623     span_lint_and_sugg(
 624         cx,
 625         COLLAPSIBLE_SPAN_LINT_CALLS,
 626         expr.span,
 627         "this call is collspible",
 628         "collapse into",
 629         format!(
 630             "span_lint_and_note({}, {}, {}, {}, {}, {})",
 631             and_then_snippets.cx,
 632             and_then_snippets.lint,
 633             and_then_snippets.span,
 634             and_then_snippets.msg,
 635             note_span,
 636             note
 637         ),
 638         Applicability::MachineApplicable,
 639     );
 640 }