Converts BinOpKind::Add to (LangItem::Add, LangItem::AddAssign), for example
Checks if the two Options are both None or some equal values as per
eq_fn.
Checks if the expression can be moved into a closure as is. This will return a list of captures
if so, otherwise, None.
Checks if the top level expression can be moved into a closure as is.
Currently checks for:
Checks if two expressions can be mutably borrowed simultaneously
and they aren’t dependent on borrowing same thing twice
Given an expression referencing a local, determines how it would be captured in a closure.
Note as this will walk up to parent expressions until the capture can be determined it should
only be used while making a closure somewhere a value is consumed. e.g. a block, match arm, or
function argument (other than a receiver).
clip unused bytes
Checks if an Expr contains a certain name.
Returns true if expr contains a return expression
Counts how many elements of the slices are equal as per eq_fn.
Resolves a def path like std::vec::Vec.
Checks if two expressions evaluate to the same value, and don’t contain any side effects.
Gets the mutability of the custom deref adjustment, if any.
If the given expression is a local binding, find the initializer expression.
If that initializer expression is another local binding, find its initializer again.
This process repeats as long as possible (but usually no more than once). Initializer
expressions with adjustments are ignored. If this is not desired, use
find_binding_init
instead.
Gets the context an expression’s value is used in.
Finds the initializer expression for a local binding. Returns None if the binding is mutable.
By only considering immutable bindings, we guarantee that the returned expression represents the
value of the binding wherever it is referenced.
Returns the DefId of the callee if the given expression is a function or method call.
Returns the DefId of the callee if the given expression is a function or method call,
as well as its node args.
Check if it’s even possible to satisfy the where clause for the item.
Returns true if the lint is #[allow]ed or #[expect]ed at any of the ids, fulfilling all
of the expectations in ids
Peels away all the compiler generated code surrounding the body of an async function,
Gets the enclosing block, if any.
Gets the loop or closure enclosing the given expression, if any.
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.
Gets the name of the item the expression is in, if available.
Gets the parent node if it’s an impl block.
Gets the parent expression, if any –- this is useful to constrain a lint.
This retrieves the parent for the given HirId if it’s an expression. This is useful for
constraint lints
Produces a path from a local caller to the type of the called method. Suitable for user
output/suggestions.
Produce a path from some local caller to the callee. Suitable for user output/suggestions.
Convenience function to get the DefId of a trait by path.
It could be a trait or trait alias.
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 }.
Returns true if the given NodeId is inside a constant context
Checks if the item of any of its parents has #[cfg(...)] attribute applied.
Returns true if the given Expr has been coerced before.
Checks if the given function kind is an async function.
Checks if a function’s body represents the identity function. Looks for bodies of the form:
Checks if id has a #[cfg(test)] attribute applied
Checks if an expression is constructing a tuple-like enum variant or struct
Checks if the def_id belongs to a function that is part of a trait impl.
Returns true if the expr is equal to Default::default() of it’s type when evaluated.
It doesn’t cover all cases, for example indirect function calls (some of std
functions are supported) but it is the best we have.
Returns true if the expr is equal to Default::default when evaluated.
Returns true if the def_id associated with the path is recognized as a “default-equivalent”
constructor from the std library
Checks if a method is defined in an impl of a diagnostic item
Checks if a method is in a diagnostic item trait
Checks if a QPath resolves to a constructor of a diagnostic item.
Checks if the DefId matches the given diagnostic item or it’s constructor.
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
Checks if the given expression is the else clause of either an if or if let expression.
Checks if the given expression is the else clause of a let else expression
Returns true if the provided def_id is an entrypoint to a program.
Returns the pre-expansion span if this comes from an expansion of the
macro
name.
See also
is_direct_expn_of.
Checks if the expression is the final expression returned from a block.
Checks if an expression represents the identity function
Only examines closures and std::convert::identity
If the expression is a path, resolves it to a DefId and checks if it matches the given path.
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:
Checks if the result of an expression is used, or it’s type is unified with another branch.
Checks if the item likely came from a proc-macro.
Checks if any parent node of HirId has #[cfg(test)] attribute applied
Returns true if the expression is in the program’s #[panic_handler].
Checks if the function containing the given HirId is a #[test] function
Checks if the given expression is a part of let else
returns true for both the init and the else part
Checks whether the given expression is a constant integer of the given value.
unlike is_integer_literal, this version does const folding
Checks whether the given expression is a constant literal of the given value.
Checks if the DefId matches the given LangItem or it’s constructor.
Returns true if the lint is allowed in the current context. This is useful for
skipping long running code when it’s unnecessary
Check if the expression return !, a type coerced from !, or could return ! if the final
expression were turned into a statement.
Returns true if the specified HirId is the top-level expression of a statement or the only
expression in a block.
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.
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.
Checks whether the given Expr is a range equivalent to a RangeFull.
For the lower bound, this means that:
Returns true if a pattern is refutable.
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(..).
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 (as defined in the
is_recursively_primitive_type function) and None otherwise.
Checks if the span actually refers to an if expression
Checks if the span actually refers to a match expression
Checks whether item either has test attribute applied, or
is a module with test in its name.
Check if parent of a hir node is a trait implementation block.
For example, f in
Checks if the given expression is a path referring an item on the trait
that is marked with the given diagnostic item.
Checks if the method call given in expr belongs to the given trait.
Checks if a given expression is a match expression expanded from the ?
operator or the try macro.
Checks if the given QPath belongs to a type alias.
Checks if given pattern is a wildcard (_)
Checks if the given DefId matches any of the paths. Returns the index of matching path, if
any.
Checks if the given DefId matches the path.
Matches a function call with the given path and returns the arguments.
Checks if the given DefId matches the libc item.
THIS METHOD IS DEPRECATED and will eventually be removed since it does not match against the
entire path or resolved DefId. Prefer using match_def_path. Consider getting a DefId from
QPath::Resolved.1.res.opt_def_id().
THIS METHOD IS DEPRECATED and will eventually be removed since it does not match against the
entire path or resolved DefId. Prefer using match_def_path. Consider getting a DefId from
QPath::Resolved.1.res.opt_def_id().
Checks if the method call given in
expr belongs to the given trait.
This is a deprecated function, consider using
is_trait_method.
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.
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.
Matches an Expr against a chain of methods, and return the matched Exprs.
Convenience function to get the nth argument type of a function.
Checks if two slices are equal as per eq_fn.
Returns whether the given let pattern and else body can be turned into a question mark
Returns true if the pattern is a PatWild, or is an ident prefixed with _
that is not locally used.
If maybe_path is a path node which resolves to an item, retrieves the item ID
If maybe_path is a path node, resolves it, otherwise returns Res::Err
If the expression is a path to a local, returns the canonical HirId of the local.
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.
Removes blocks around an expression, only if the block contains just one expression
and no statements. Unsafe blocks are not removed.
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.
Peels off all references on the expression. Returns the underlying expression and the number of
references removed.
Peels off all unary operators of an expression. Returns the underlying expression and the number
of operators removed.
Peels of expressions while the given closure returns Some.
Peels off all references on the pattern. Returns the underlying pattern and the number of
references removed.
Peels off all references on the type. Returns the underlying type and the number of references
removed.
Peels off up to the given number of references on the expression. Returns the underlying
expression and the number of references removed.
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.
This method will return tuple of projection stack and root of the expression,
used in can_mut_borrow_both.
If the pattern is an or pattern, call the function once for each sub pattern. Otherwise, call
the function once on the given pattern.
Convenience function to get the return type of a function.
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
Turn a constant int byte representation into an i128
Checks whether a given span has any comment token
This checks for all types of comment: line “//”, block “/**”, doc “///” “//!”
Returns all the comments a given span contains
Tokenizes the input while keeping the text associated with each token.
Gets the hir::TraitRef of the trait the given method is implemented for.
clip unused bytes
Walks up the HIR tree from the given expression in an attempt to find where the value is
consumed.