Crate clippy_utils

Re-exports

• pub use self::attrs::*;

Modules

• ast_utils
  Utilities for manipulating and extracting information from rustc_ast::ast.
• attrs
• check_proc_macro 🔒
  This module handles checking if the span given is from a proc-macro or not.
• comparisons
  Utility functions for comparison operators.
• consts
• diagnostics
  Clippy wrappers around rustc’s diagnostic functions.
• eager_or_lazy
  Utilities for evaluating whether eagerly evaluated expressions can be made lazy and vice versa.
• higher
  This module contains functions that retrieve specific elements.
• hir_utils 🔒
• macros
• mir
• numeric_literal
• paths
  This module contains paths to types and functions Clippy needs to know about.
• ptr
• qualify_min_const_fn
• source
  Utils for extracting, inspecting or transforming source code
• str_utils
• sugg
  Contains utility functions to generate suggestions.
• sym_helper
• ty
  Util methods for rustc_middle::ty
• usage
• visitors

Macros

• extract_msrv_attr
• maybe_path 🔒
• op_utils 🔒
• sym
  Convenience wrapper around rustc’s Symbol::intern

Structs

• ContainsName
• ExprUseCtxt
  The context an expressions value is used in.
• HirEqInterExpr
• SpanlessEq
  Type used to check whether two ast are the same. This is different from the operator == on ast types as this operator would compare true equality with ID and span.
• SpanlessHash
  Type used to hash an ast element. This is different from the Hash trait on ast types as this trait would consider IDs and spans.

Enums

• CaptureKind
  How a local is captured by a closure
• DefinedTy
  A type definition as it would be viewed from within a function.
• ExprUseNode
  The node which consumes a value.
• RequiresSemi

Statics

• BINOP_TRAITS
  Binary operation traits like LangItem::Add
• OP_ASSIGN_TRAITS
  Operator-Assign traits like LangItem::AddAssign
• TEST_ITEM_NAMES_CACHE 🔒

Traits

• MaybePath

Functions

• any_parent_has_attr
• binary_expr_needs_parentheses
  Returns true if the given expr is binary expression that needs to be wrapped in parentheses.
• binop_traits
  Converts BinOpKind::Add to (LangItem::Add, LangItem::AddAssign), for example
• both
  Checks if the two Options are both None or some equal values as per eq_fn.
• can_move_expr_to_closure
  Checks if the expression can be moved into a closure as is. This will return a list of captures if so, otherwise, None.
• can_move_expr_to_closure_no_visit
  Checks if the top level expression can be moved into a closure as is. Currently checks for:
• can_mut_borrow_both
  Checks if two expressions can be mutably borrowed simultaneously and they aren’t dependent on borrowing same thing twice
• capture_local_usage
  Given an expression referencing a local, determines how it would be captured in a closure.
• clip
  clip unused bytes
• contains_name
  Checks if an Expr contains a certain name.
• contains_return
  Returns true if expr contains a return expression
• count_eq
  Counts how many elements of the slices are equal as per eq_fn.
• create_disallowed_map
  Creates a map of disallowed items to the reason they were disallowed.
• def_path_def_ids
  Resolves a def path like std::vec::Vec to its DefIds, see def_path_res.
• def_path_res
  Resolves a def path like std::vec::Vec.
• def_path_res_with_base
  Resolves a def path like vec::Vec with the base std.
• eq_expr_value
  Checks if two expressions evaluate to the same value, and don’t contain any side effects.
• expr_custom_deref_adjustment
  Gets the mutability of the custom deref adjustment, if any.
• expr_or_init
  If the given expression is a local binding, find the initializer expression. If that initializer expression is another local binding, find its initializer again.
• expr_use_ctxt
  Gets the context an expression’s value is used in.
• find_binding_init
  Finds the initializer expression for a local binding. Returns None if the binding is mutable.
• find_crates
  Finds the crates called name, may be multiple due to multiple major versions.
• find_primitive_impls 🔒
• fn_def_id
  Returns the DefId of the callee if the given expression is a function or method call.
• fn_def_id_with_node_args
  Returns the DefId of the callee if the given expression is a function or method call, as well as its node args.
• fn_has_unsatisfiable_preds
  Check if it’s even possible to satisfy the where clause for the item.
• fulfill_or_allowed
  Returns true if the lint is #[allow]ed or #[expect]ed at any of the ids, fulfilling all of the expectations in ids
• get_async_fn_body
  Peels away all the compiler generated code surrounding the body of an async function,
• get_enclosing_block
  Gets the enclosing block, if any.
• get_enclosing_loop_or_multi_call_closure
  Gets the loop or closure enclosing the given expression, if any.
• get_expr_use_or_unification_node
  Gets the node where an expression is either used, or it’s type is unified with another branch. Returns both the node and the HirId of the closest child node.
• get_item_name
  Gets the name of the item the expression is in, if available.
• get_parent_as_impl
  Gets the parent node if it’s an impl block.
• get_parent_expr
  Gets the parent expression, if any –- this is useful to constrain a lint.
• get_parent_expr_for_hir
  This retrieves the parent for the given HirId if it’s an expression. This is useful for constraint lints
• get_path_from_caller_to_method_type
  Produces a path from a local caller to the type of the called method. Suitable for user output/suggestions.
• get_path_to_callee 🔒
  Produce a path from some local caller to the callee. Suitable for user output/suggestions.
• get_path_to_ty 🔒
• get_trait_def_id
  Convenience function to get the DefId of a trait by path. It could be a trait or trait alias.
• has_attr
• has_repr_attr
• hash_expr
• hash_stmt
• if_sequence
  Returns the list of condition expressions and the list of blocks in a sequence of if/else. E.g., this returns ([a, b], [c, d, e]) for the expression if a { c } else if b { d } else { e }.
• in_automatically_derived
  Checks if the given HIR node is inside an impl block with the automatically_derived attribute.
• inherits_cfg
  Checks if the item of any of its parents has #[cfg(...)] attribute applied.
• int_bits
• is_adjusted
  Returns true if the given Expr has been coerced before.
• is_async_fn
  Checks if the given function kind is an async function.
• is_block_like
  Returns true if the given expr is a block or resembled as a block, such as if, loop, match expressions etc.
• is_body_identity_function 🔒
  Checks if a function’s body represents the identity function. Looks for bodies of the form:
• is_bool
• is_cfg_test
  Checks if id has a #[cfg(test)] attribute applied
• is_ctor_or_promotable_const_function
  Checks if an expression is constructing a tuple-like enum variant or struct
• is_def_id_trait_method
  Checks if the def_id belongs to a function that is part of a trait impl.
• is_default_equivalent
  Returns true if the expr is equal to Default::default() of it’s type when evaluated.
• is_default_equivalent_call
  Returns true if the expr is equal to Default::default when evaluated.
• is_default_equivalent_ctor 🔒
  Returns true if the def_id associated with the path is recognized as a “default-equivalent” constructor from the std library
• is_default_equivalent_from 🔒
• is_diag_item_method
  Checks if a method is defined in an impl of a diagnostic item
• is_diag_trait_item
  Checks if a method is in a diagnostic item trait
• is_diagnostic_item_or_ctor
  Checks if the DefId matches the given diagnostic item or it’s constructor.
• is_direct_expn_of
  Returns the pre-expansion span if the span directly comes from an expansion of the macro name. The difference with is_expn_of is that in
• is_else_clause
  Checks if the given expression is the else clause of either an if or if let expression.
• is_else_clause_in_let_else
  Checks if the given expression is the else clause of a let else expression
• is_entrypoint_fn
  Returns true if the provided def_id is an entrypoint to a program.
• is_enum_variant_ctor
  Checks if {ctor_call_id}(...) is {enum_item}::{variant_name}(...).
• is_expn_of
  Returns the pre-expansion span if this comes from an expansion of the macro name. See also is_direct_expn_of.
• is_expr_final_block_expr
  Checks if the expression is the final expression returned from a block.
• is_expr_identity_function
  Checks if an expression represents the identity function Only examines closures and std::convert::identity
• is_expr_path_def_path
  If the expression is a path, resolves it to a DefId and checks if it matches the given path.
• is_expr_untyped_identity_function
  This is the same as is_expr_identity_function, but does not consider closures with type annotations for its bindings (or similar) as identity functions:
• is_expr_used_or_unified
  Checks if the result of an expression is used, or it’s type is unified with another branch.
• is_from_proc_macro
  Checks if the item likely came from a proc-macro.
• is_hir_ty_cfg_dependant
• is_in_cfg_test
  Checks if any parent node of HirId has #[cfg(test)] attribute applied
• is_in_const_context
  Checks if we are currently in a const context (e.g. const fn, static/const initializer).
• is_in_panic_handler
  Returns true if the expression is in the program’s #[panic_handler].
• is_in_test
  Checks if the node is in a #[test] function or has any parent node marked #[cfg(test)]
• is_in_test_function
  Checks if the function containing the given HirId is a #[test] function
• is_inherent_method_call
  Checks if the given method call expression calls an inherent method.
• is_inside_always_const_context
  Returns true if the given HirId is inside an always constant context.
• is_inside_let_else
  Checks if the given expression is a part of let else returns true for both the init and the else part
• is_integer_const
  Checks whether the given expression is a constant integer of the given value. unlike is_integer_literal, this version does const folding
• is_integer_literal
  Checks whether the given expression is a constant literal of the given value.
• is_lang_item_or_ctor
  Checks if the DefId matches the given LangItem or it’s constructor.
• is_lint_allowed
  Returns true if the lint is allowed in the current context. This is useful for skipping long running code when it’s unnecessary
• is_must_use_func_call
• is_never_expr
  Check if the expression return !, a type coerced from !, or could return ! if the final expression were turned into a statement.
• is_no_core_crate
• is_no_std_crate
• is_parent_stmt
  Returns true if the specified HirId is the top-level expression of a statement or the only expression in a block.
• is_path_diagnostic_item
  If maybe_path is a path node which resolves to an item, resolves it to a DefId and checks if it matches the given diagnostic item.
• is_path_lang_item
  If maybe_path is a path node which resolves to an item, resolves it to a DefId and checks if it matches the given lang item.
• is_range_full
  Checks whether the given Expr is a range equivalent to a RangeFull.
• is_receiver_of_method_call
  Returns true if the specified expression is in a receiver position.
• is_refutable
  Returns true if a pattern is refutable.
• is_res_lang_ctor
  Checks if a Res refers to a constructor of a LangItem For example, use this to check whether a function call or a pattern is Some(..).
• is_self
• is_self_ty
• is_slice_of_primitives
  Returns Option<String> where String is a textual representation of the type encapsulated in the slice iff the given expression is a slice of primitives.
• is_span_if
  Checks if the span actually refers to an if expression
• is_span_match
  Checks if the span actually refers to a match expression
• is_trait_impl_item
  Check if parent of a hir node is a trait implementation block. For example, f in
• is_trait_item
  Checks if the given expression is a path referring an item on the trait that is marked with the given diagnostic item.
• is_trait_method
  Checks if the method call given in expr belongs to the given trait.
• is_try
  Checks if a given expression is a match expression expanded from the ? operator or the try macro.
• is_ty_alias
  Checks if the given QPath belongs to a type alias.
• is_unit_expr
• is_wild
  Checks if given pattern is a wildcard (_)
• item_children_by_name 🔒
• iter_input_pats
• last_path_segment
• local_is_initialized
  Checks if the given local has an initializer or is from something other than a let statement
• local_item_children_by_name 🔒
• match_any_def_paths
  Checks if the given DefId matches any of the paths. Returns the index of matching path, if any.
• match_def_path
  Checks if the given DefId matches the path.
• match_function_call
  Matches a function call with the given path and returns the arguments.
• match_function_call_with_def_id
• match_libc_symbol
  Checks if the given DefId matches the libc item.
• match_path
  THIS METHOD IS DEPRECATED. Matches a Path against a slice of segment string literals.
• match_qpath
  THIS METHOD IS DEPRECATED. Matches a QPath against a slice of segment string literals.
• match_trait_method
  Checks if the method call given in expr belongs to the given trait. This is a deprecated function, consider using is_trait_method.
• maybe_get_relative_path 🔒
  Tries to produce a relative path from from to to; if such a path would contain more than max_super super items, produces an absolute path instead. Both from and to should be in the local crate.
• method_calls
  Returns the method names and argument list of nested method call expressions that make up expr. method/span lists are sorted with the most recent call first.
• method_chain_args
  Matches an Expr against a chain of methods, and return the matched Exprs.
• non_local_item_children_by_name 🔒
• nth_arg
  Convenience function to get the nth argument type of a function.
• over
  Checks if two slices are equal as per eq_fn.
• pat_and_expr_can_be_question_mark
  Returns whether the given let pattern and else body can be turned into a question mark
• pat_is_wild
  Returns true if the pattern is a PatWild, or is an ident prefixed with _ that is not locally used.
• path_def_id
  If maybe_path is a path node which resolves to an item, retrieves the item ID
• path_res
  If maybe_path is a path node, resolves it, otherwise returns Res::Err
• path_to_local
  If the expression is a path to a local, returns the canonical HirId of the local.
• path_to_local_id
  Returns true if the expression is a path to a local with the specified HirId. Use this function to see if an expression matches a function argument or a match binding.
• peel_blocks
  Removes blocks around an expression, only if the block contains just one expression and no statements. Unsafe blocks are not removed.
• peel_blocks_with_stmt
  Removes blocks around an expression, only if the block contains just one expression or just one expression statement with a semicolon. Unsafe blocks are not removed.
• peel_hir_expr_refs
  Peels off all references on the expression. Returns the underlying expression and the number of references removed.
• peel_hir_expr_unary
  Peels off all unary operators of an expression. Returns the underlying expression and the number of operators removed.
• peel_hir_expr_while
  Peels of expressions while the given closure returns Some.
• peel_hir_pat_refs
  Peels off all references on the pattern. Returns the underlying pattern and the number of references removed.
• peel_hir_ty_refs
  Peels off all references on the type. Returns the underlying type and the number of references removed.
• peel_middle_ty_refs
  Peels off all references on the type. Returns the underlying type and the number of references removed.
• peel_n_hir_expr_refs
  Peels off up to the given number of references on the expression. Returns the underlying expression and the number of references removed.
• peel_ref_operators
  Removes AddrOf operators (&) or deref operators (*), but only if a reference type is dereferenced. An overloaded deref such as Vec to slice would not be removed.
• projection_stack 🔒
  This method will return tuple of projection stack and root of the expression, used in can_mut_borrow_both.
• qpath_generic_tys
• recurse_or_patterns
  If the pattern is an or pattern, call the function once for each sub pattern. Otherwise, call the function once on the given pattern.
• return_ty
  Convenience function to get the return type of a function.
• search_same
  Returns list of all pairs (a, b) where eq(a, b) == true and a is before b in exprs for all a and b in exprs
• sext
  Turn a constant int byte representation into an i128
• span_contains_comment
  Checks whether a given span has any comment token This checks for all types of comment: line “//”, block “/**”, doc “///” “//!”
• span_extract_comment
  Returns all the comments a given span contains
• span_find_starting_semi
• std_or_core
• strip_pat_refs
• tokenize_with_text
  Tokenizes the input while keeping the text associated with each token.
• trait_ref_of_method
  Gets the hir::TraitRef of the trait the given method is implemented for.
• unsext
  clip unused bytes
• walk_to_expr_usage
  Walks up the HIR tree from the given expression in an attempt to find where the value is consumed.
• with_test_item_names 🔒

Type Aliases

• MethodArguments
  Arguments of a method: the receiver and all the additional arguments.