Implement field_reassign_with_default
- Implement `field_reassign_with_default` as a `LateLintPass` - Avoid triggering `default_trait_access` on a span already linted by `field_reassigned_with_default` - Merge `default_trait_access` and `field_reassign_with_default` into `Default` - Co-authored-by: Eduardo Broto <ebroto@tutanota.com> - Fixes #568
This commit is contained in:
Henri Lunnikivi
Henri Lunnikivi
parent
e298c830af
commit
7b203f3da6
@ -1714,6 +1714,7 @@ Released 2018-09-13
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[`extend_from_slice`]: https://rust-lang.github.io/rust-clippy/master/index.html#extend_from_slice
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[`extra_unused_lifetimes`]: https://rust-lang.github.io/rust-clippy/master/index.html#extra_unused_lifetimes
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[`fallible_impl_from`]: https://rust-lang.github.io/rust-clippy/master/index.html#fallible_impl_from
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[`field_reassign_with_default`]: https://rust-lang.github.io/rust-clippy/master/index.html#field_reassign_with_default
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[`filetype_is_file`]: https://rust-lang.github.io/rust-clippy/master/index.html#filetype_is_file
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[`filter_map`]: https://rust-lang.github.io/rust-clippy/master/index.html#filter_map
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[`filter_map_next`]: https://rust-lang.github.io/rust-clippy/master/index.html#filter_map_next
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304
clippy_lints/src/default.rs
Normal file
304
clippy_lints/src/default.rs
Normal file
@ -0,0 +1,304 @@
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use crate::utils::{any_parent_is_automatically_derived, contains_name, match_def_path, paths, qpath_res, snippet};
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use crate::utils::{span_lint_and_note, span_lint_and_sugg};
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use if_chain::if_chain;
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use rustc_data_structures::fx::FxHashSet;
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use rustc_errors::Applicability;
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use rustc_hir::def::Res;
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use rustc_hir::{Block, Expr, ExprKind, PatKind, QPath, Stmt, StmtKind};
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_middle::ty::{self, Adt, Ty};
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use rustc_session::{declare_tool_lint, impl_lint_pass};
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use rustc_span::symbol::{Ident, Symbol};
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use rustc_span::Span;
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declare_clippy_lint! {
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/// **What it does:** Checks for literal calls to `Default::default()`.
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///
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/// **Why is this bad?** It's more clear to the reader to use the name of the type whose default is
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/// being gotten than the generic `Default`.
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///
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/// **Known problems:** None.
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///
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/// **Example:**
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/// ```rust
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/// // Bad
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/// let s: String = Default::default();
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///
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/// // Good
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/// let s = String::default();
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/// ```
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pub DEFAULT_TRAIT_ACCESS,
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pedantic,
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"checks for literal calls to `Default::default()`"
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}
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declare_clippy_lint! {
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/// **What it does:** Checks for immediate reassignment of fields initialized
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/// with Default::default().
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///
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/// **Why is this bad?**It's more idiomatic to use the [functional update syntax](https://doc.rust-lang.org/reference/expressions/struct-expr.html#functional-update-syntax).
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///
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/// **Known problems:** Assignments to patterns that are of tuple type are not linted.
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///
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/// **Example:**
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/// Bad:
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/// ```
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/// # #[derive(Default)]
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/// # struct A { i: i32 }
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/// let mut a: A = Default::default();
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/// a.i = 42;
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/// ```
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/// Use instead:
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/// ```
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/// # #[derive(Default)]
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/// # struct A { i: i32 }
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/// let a = A {
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/// i: 42,
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/// .. Default::default()
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/// };
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/// ```
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pub FIELD_REASSIGN_WITH_DEFAULT,
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style,
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"binding initialized with Default should have its fields set in the initializer"
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}
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#[derive(Default)]
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pub struct Default {
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// Spans linted by `field_reassign_with_default`.
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reassigned_linted: FxHashSet<Span>,
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}
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impl_lint_pass!(Default => [DEFAULT_TRAIT_ACCESS, FIELD_REASSIGN_WITH_DEFAULT]);
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impl LateLintPass<'_> for Default {
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fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
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if_chain! {
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// Avoid cases already linted by `field_reassign_with_default`
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if !self.reassigned_linted.contains(&expr.span);
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if let ExprKind::Call(ref path, ..) = expr.kind;
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if !any_parent_is_automatically_derived(cx.tcx, expr.hir_id);
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if let ExprKind::Path(ref qpath) = path.kind;
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if let Some(def_id) = cx.qpath_res(qpath, path.hir_id).opt_def_id();
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if match_def_path(cx, def_id, &paths::DEFAULT_TRAIT_METHOD);
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// Detect and ignore <Foo as Default>::default() because these calls do explicitly name the type.
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if let QPath::Resolved(None, _path) = qpath;
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then {
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let expr_ty = cx.typeck_results().expr_ty(expr);
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if let ty::Adt(def, ..) = expr_ty.kind() {
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// TODO: Work out a way to put "whatever the imported way of referencing
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// this type in this file" rather than a fully-qualified type.
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let replacement = format!("{}::default()", cx.tcx.def_path_str(def.did));
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span_lint_and_sugg(
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cx,
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DEFAULT_TRAIT_ACCESS,
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expr.span,
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&format!("calling `{}` is more clear than this expression", replacement),
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"try",
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replacement,
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Applicability::Unspecified, // First resolve the TODO above
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);
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}
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}
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}
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}
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fn check_block<'tcx>(&mut self, cx: &LateContext<'tcx>, block: &Block<'tcx>) {
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// find all binding statements like `let mut _ = T::default()` where `T::default()` is the
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// `default` method of the `Default` trait, and store statement index in current block being
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// checked and the name of the bound variable
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let binding_statements_using_default = enumerate_bindings_using_default(cx, block);
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// start from the `let mut _ = _::default();` and look at all the following
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// statements, see if they re-assign the fields of the binding
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for (stmt_idx, binding_name, binding_type, span) in binding_statements_using_default {
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// the last statement of a block cannot trigger the lint
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if stmt_idx == block.stmts.len() - 1 {
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break;
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}
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// find all "later statement"'s where the fields of the binding set as
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// Default::default() get reassigned, unless the reassignment refers to the original binding
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let mut first_assign = None;
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let mut assigned_fields = Vec::new();
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let mut cancel_lint = false;
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for consecutive_statement in &block.stmts[stmt_idx + 1..] {
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// interrupt if the statement is a let binding (`Local`) that shadows the original
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// binding
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if stmt_shadows_binding(consecutive_statement, binding_name) {
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break;
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}
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// find out if and which field was set by this `consecutive_statement`
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else if let Some((field_ident, assign_rhs)) =
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field_reassigned_by_stmt(consecutive_statement, binding_name)
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{
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// interrupt and cancel lint if assign_rhs references the original binding
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if contains_name(binding_name, assign_rhs) {
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cancel_lint = true;
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break;
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}
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// if the field was previously assigned, replace the assignment, otherwise insert the assignment
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if let Some(prev) = assigned_fields
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.iter_mut()
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.find(|(field_name, _)| field_name == &field_ident.name)
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{
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*prev = (field_ident.name, assign_rhs);
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} else {
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assigned_fields.push((field_ident.name, assign_rhs));
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}
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// also set first instance of error for help message
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if first_assign.is_none() {
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first_assign = Some(consecutive_statement);
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}
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}
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// interrupt also if no field was assigned, since we only want to look at consecutive statements
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else {
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break;
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}
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}
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// if there are incorrectly assigned fields, do a span_lint_and_note to suggest
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// construction using `Ty { fields, ..Default::default() }`
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if !assigned_fields.is_empty() && !cancel_lint {
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// take the original assignment as span
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let stmt = &block.stmts[stmt_idx];
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if let StmtKind::Local(preceding_local) = &stmt.kind {
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// filter out fields like `= Default::default()`, because the FRU already covers them
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let assigned_fields = assigned_fields
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.into_iter()
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.filter(|(_, rhs)| !is_expr_default(rhs, cx))
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.collect::<Vec<(Symbol, &Expr<'_>)>>();
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// if all fields of the struct are not assigned, add `.. Default::default()` to the suggestion.
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let ext_with_default = !fields_of_type(binding_type)
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.iter()
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.all(|field| assigned_fields.iter().any(|(a, _)| a == &field.name));
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let field_list = assigned_fields
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.into_iter()
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.map(|(field, rhs)| {
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// extract and store the assigned value for help message
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let value_snippet = snippet(cx, rhs.span, "..");
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format!("{}: {}", field, value_snippet)
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})
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.collect::<Vec<String>>()
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.join(", ");
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let sugg = if ext_with_default {
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if field_list.is_empty() {
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format!("{}::default()", binding_type)
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} else {
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format!("{} {{ {}, ..Default::default() }}", binding_type, field_list)
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}
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} else {
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format!("{} {{ {} }}", binding_type, field_list)
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};
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// span lint once per statement that binds default
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span_lint_and_note(
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cx,
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FIELD_REASSIGN_WITH_DEFAULT,
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first_assign.unwrap().span,
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"field assignment outside of initializer for an instance created with Default::default()",
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Some(preceding_local.span),
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&format!(
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"consider initializing the variable with `{}` and removing relevant reassignments",
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sugg
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),
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);
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self.reassigned_linted.insert(span);
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}
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}
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}
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}
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}
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/// Checks if the given expression is the `default` method belonging to the `Default` trait.
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fn is_expr_default<'tcx>(expr: &'tcx Expr<'tcx>, cx: &LateContext<'tcx>) -> bool {
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if_chain! {
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if let ExprKind::Call(ref fn_expr, _) = &expr.kind;
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if let ExprKind::Path(qpath) = &fn_expr.kind;
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if let Res::Def(_, def_id) = qpath_res(cx, qpath, fn_expr.hir_id);
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then {
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// right hand side of assignment is `Default::default`
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match_def_path(cx, def_id, &paths::DEFAULT_TRAIT_METHOD)
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} else {
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false
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}
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}
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}
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/// Returns the block indices, identifiers and types of bindings set as `Default::default()`, except
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/// for when the pattern type is a tuple.
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fn enumerate_bindings_using_default<'tcx>(
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cx: &LateContext<'tcx>,
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block: &Block<'tcx>,
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) -> Vec<(usize, Symbol, Ty<'tcx>, Span)> {
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block
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.stmts
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.iter()
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.enumerate()
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.filter_map(|(idx, stmt)| {
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if_chain! {
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// only take `let ...` statements
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if let StmtKind::Local(ref local) = stmt.kind;
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// only take bindings to identifiers
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if let PatKind::Binding(_, _, ident, _) = local.pat.kind;
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// that are not tuples
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let ty = cx.typeck_results().pat_ty(local.pat);
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if !matches!(ty.kind(), ty::Tuple(_));
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// only when assigning `... = Default::default()`
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if let Some(ref expr) = local.init;
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if is_expr_default(expr, cx);
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then {
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Some((idx, ident.name, ty, expr.span))
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} else {
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None
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}
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}
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})
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.collect()
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}
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fn stmt_shadows_binding(this: &Stmt<'_>, shadowed: Symbol) -> bool {
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if let StmtKind::Local(local) = &this.kind {
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if let PatKind::Binding(_, _, ident, _) = local.pat.kind {
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return ident.name == shadowed;
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}
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}
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false
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}
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/// Returns the reassigned field and the assigning expression (right-hand side of assign).
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fn field_reassigned_by_stmt<'tcx>(this: &Stmt<'tcx>, binding_name: Symbol) -> Option<(Ident, &'tcx Expr<'tcx>)> {
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if_chain! {
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// only take assignments
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if let StmtKind::Semi(ref later_expr) = this.kind;
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if let ExprKind::Assign(ref assign_lhs, ref assign_rhs, _) = later_expr.kind;
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// only take assignments to fields where the left-hand side field is a field of
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// the same binding as the previous statement
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if let ExprKind::Field(ref binding, field_ident) = assign_lhs.kind;
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if let ExprKind::Path(ref qpath) = binding.kind;
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if let QPath::Resolved(_, path) = qpath;
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if let Some(second_binding_name) = path.segments.last();
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if second_binding_name.ident.name == binding_name;
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then {
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Some((field_ident, assign_rhs))
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} else {
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None
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}
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}
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}
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/// Returns the vec of fields for a struct and an empty vec for non-struct ADTs.
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fn fields_of_type(ty: Ty<'_>) -> Vec<Ident> {
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if let Adt(adt, _) = ty.kind() {
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if adt.is_struct() {
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let variant = &adt.non_enum_variant();
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return variant.fields.iter().map(|f| f.ident).collect();
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}
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}
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vec![]
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}
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@ -1,62 +0,0 @@
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use if_chain::if_chain;
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use rustc_errors::Applicability;
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use rustc_hir::{Expr, ExprKind, QPath};
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use rustc_lint::{LateContext, LateLintPass};
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use rustc_middle::ty;
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use rustc_session::{declare_lint_pass, declare_tool_lint};
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use crate::utils::{any_parent_is_automatically_derived, match_def_path, paths, span_lint_and_sugg};
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declare_clippy_lint! {
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/// **What it does:** Checks for literal calls to `Default::default()`.
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///
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/// **Why is this bad?** It's more clear to the reader to use the name of the type whose default is
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/// being gotten than the generic `Default`.
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///
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/// **Known problems:** None.
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///
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/// **Example:**
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/// ```rust
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/// // Bad
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/// let s: String = Default::default();
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///
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/// // Good
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/// let s = String::default();
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/// ```
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pub DEFAULT_TRAIT_ACCESS,
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pedantic,
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"checks for literal calls to `Default::default()`"
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}
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declare_lint_pass!(DefaultTraitAccess => [DEFAULT_TRAIT_ACCESS]);
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impl<'tcx> LateLintPass<'tcx> for DefaultTraitAccess {
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fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
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if_chain! {
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if let ExprKind::Call(ref path, ..) = expr.kind;
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if !any_parent_is_automatically_derived(cx.tcx, expr.hir_id);
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if let ExprKind::Path(ref qpath) = path.kind;
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if let Some(def_id) = cx.qpath_res(qpath, path.hir_id).opt_def_id();
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if match_def_path(cx, def_id, &paths::DEFAULT_TRAIT_METHOD);
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// Detect and ignore <Foo as Default>::default() because these calls do explicitly name the type.
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if let QPath::Resolved(None, _path) = qpath;
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then {
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let expr_ty = cx.typeck_results().expr_ty(expr);
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if let ty::Adt(def, ..) = expr_ty.kind() {
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// TODO: Work out a way to put "whatever the imported way of referencing
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// this type in this file" rather than a fully-qualified type.
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let replacement = format!("{}::default()", cx.tcx.def_path_str(def.did));
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span_lint_and_sugg(
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cx,
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DEFAULT_TRAIT_ACCESS,
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expr.span,
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&format!("calling `{}` is more clear than this expression", replacement),
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"try",
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replacement,
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Applicability::Unspecified, // First resolve the TODO above
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);
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}
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}
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}
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}
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}
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@ -176,7 +176,7 @@ macro_rules! declare_clippy_lint {
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mod copy_iterator;
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mod create_dir;
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mod dbg_macro;
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mod default_trait_access;
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mod default;
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mod dereference;
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mod derive;
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mod disallowed_method;
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@ -537,7 +537,8 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
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©_iterator::COPY_ITERATOR,
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&create_dir::CREATE_DIR,
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&dbg_macro::DBG_MACRO,
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&default_trait_access::DEFAULT_TRAIT_ACCESS,
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&default::DEFAULT_TRAIT_ACCESS,
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&default::FIELD_REASSIGN_WITH_DEFAULT,
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&dereference::EXPLICIT_DEREF_METHODS,
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&derive::DERIVE_HASH_XOR_EQ,
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&derive::DERIVE_ORD_XOR_PARTIAL_ORD,
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@ -1049,7 +1050,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
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store.register_late_pass(|| box neg_cmp_op_on_partial_ord::NoNegCompOpForPartialOrd);
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store.register_late_pass(|| box unwrap::Unwrap);
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store.register_late_pass(|| box duration_subsec::DurationSubsec);
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store.register_late_pass(|| box default_trait_access::DefaultTraitAccess);
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store.register_late_pass(|| box indexing_slicing::IndexingSlicing);
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store.register_late_pass(|| box non_copy_const::NonCopyConst);
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store.register_late_pass(|| box ptr_offset_with_cast::PtrOffsetWithCast);
|
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@ -1100,6 +1100,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
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let enum_variant_name_threshold = conf.enum_variant_name_threshold;
|
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store.register_early_pass(move || box enum_variants::EnumVariantNames::new(enum_variant_name_threshold));
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||||
store.register_early_pass(|| box tabs_in_doc_comments::TabsInDocComments);
|
||||
store.register_late_pass(|| box default::Default::default());
|
||||
store.register_late_pass(|| box unused_self::UnusedSelf);
|
||||
store.register_late_pass(|| box mutable_debug_assertion::DebugAssertWithMutCall);
|
||||
store.register_late_pass(|| box exit::Exit);
|
||||
@ -1212,7 +1213,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
|
||||
LintId::of(&checked_conversions::CHECKED_CONVERSIONS),
|
||||
LintId::of(&copies::SAME_FUNCTIONS_IN_IF_CONDITION),
|
||||
LintId::of(©_iterator::COPY_ITERATOR),
|
||||
LintId::of(&default_trait_access::DEFAULT_TRAIT_ACCESS),
|
||||
LintId::of(&default::DEFAULT_TRAIT_ACCESS),
|
||||
LintId::of(&dereference::EXPLICIT_DEREF_METHODS),
|
||||
LintId::of(&derive::EXPL_IMPL_CLONE_ON_COPY),
|
||||
LintId::of(&derive::UNSAFE_DERIVE_DESERIALIZE),
|
||||
@ -1321,6 +1322,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
|
||||
LintId::of(&comparison_chain::COMPARISON_CHAIN),
|
||||
LintId::of(&copies::IFS_SAME_COND),
|
||||
LintId::of(&copies::IF_SAME_THEN_ELSE),
|
||||
LintId::of(&default::FIELD_REASSIGN_WITH_DEFAULT),
|
||||
LintId::of(&derive::DERIVE_HASH_XOR_EQ),
|
||||
LintId::of(&derive::DERIVE_ORD_XOR_PARTIAL_ORD),
|
||||
LintId::of(&doc::MISSING_SAFETY_DOC),
|
||||
@ -1581,6 +1583,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
|
||||
LintId::of(&blocks_in_if_conditions::BLOCKS_IN_IF_CONDITIONS),
|
||||
LintId::of(&collapsible_if::COLLAPSIBLE_IF),
|
||||
LintId::of(&comparison_chain::COMPARISON_CHAIN),
|
||||
LintId::of(&default::FIELD_REASSIGN_WITH_DEFAULT),
|
||||
LintId::of(&doc::MISSING_SAFETY_DOC),
|
||||
LintId::of(&doc::NEEDLESS_DOCTEST_MAIN),
|
||||
LintId::of(&enum_variants::ENUM_VARIANT_NAMES),
|
||||
|
||||
@ -359,7 +359,7 @@
|
||||
group: "pedantic",
|
||||
desc: "checks for literal calls to `Default::default()`",
|
||||
deprecation: None,
|
||||
module: "default_trait_access",
|
||||
module: "default",
|
||||
},
|
||||
Lint {
|
||||
name: "deprecated_cfg_attr",
|
||||
@ -627,6 +627,13 @@
|
||||
deprecation: None,
|
||||
module: "fallible_impl_from",
|
||||
},
|
||||
Lint {
|
||||
name: "field_reassign_with_default",
|
||||
group: "style",
|
||||
desc: "binding initialized with Default should have its fields set in the initializer",
|
||||
deprecation: None,
|
||||
module: "default",
|
||||
},
|
||||
Lint {
|
||||
name: "filetype_is_file",
|
||||
group: "restriction",
|
||||
|
||||
110
tests/ui/field_reassign_with_default.rs
Normal file
110
tests/ui/field_reassign_with_default.rs
Normal file
@ -0,0 +1,110 @@
|
||||
#![warn(clippy::field_reassign_with_default)]
|
||||
|
||||
#[derive(Default)]
|
||||
struct A {
|
||||
i: i32,
|
||||
j: i64,
|
||||
}
|
||||
|
||||
struct B {
|
||||
i: i32,
|
||||
j: i64,
|
||||
}
|
||||
|
||||
/// Implements .next() that returns a different number each time.
|
||||
struct SideEffect(i32);
|
||||
|
||||
impl SideEffect {
|
||||
fn new() -> SideEffect {
|
||||
SideEffect(0)
|
||||
}
|
||||
fn next(&mut self) -> i32 {
|
||||
self.0 += 1;
|
||||
self.0
|
||||
}
|
||||
}
|
||||
|
||||
fn main() {
|
||||
// wrong, produces first error in stderr
|
||||
let mut a: A = Default::default();
|
||||
a.i = 42;
|
||||
|
||||
// right
|
||||
let mut a: A = Default::default();
|
||||
|
||||
// right
|
||||
let a = A {
|
||||
i: 42,
|
||||
..Default::default()
|
||||
};
|
||||
|
||||
// right
|
||||
let mut a: A = Default::default();
|
||||
if a.i == 0 {
|
||||
a.j = 12;
|
||||
}
|
||||
|
||||
// right
|
||||
let mut a: A = Default::default();
|
||||
let b = 5;
|
||||
|
||||
// right
|
||||
let mut b = 32;
|
||||
let mut a: A = Default::default();
|
||||
b = 2;
|
||||
|
||||
// right
|
||||
let b: B = B { i: 42, j: 24 };
|
||||
|
||||
// right
|
||||
let mut b: B = B { i: 42, j: 24 };
|
||||
b.i = 52;
|
||||
|
||||
// right
|
||||
let mut b = B { i: 15, j: 16 };
|
||||
let mut a: A = Default::default();
|
||||
b.i = 2;
|
||||
|
||||
// wrong, produces second error in stderr
|
||||
let mut a: A = Default::default();
|
||||
a.j = 43;
|
||||
a.i = 42;
|
||||
|
||||
// wrong, produces third error in stderr
|
||||
let mut a: A = Default::default();
|
||||
a.i = 42;
|
||||
a.j = 43;
|
||||
a.j = 44;
|
||||
|
||||
// wrong, produces fourth error in stderr
|
||||
let mut a = A::default();
|
||||
a.i = 42;
|
||||
|
||||
// wrong, but does not produce an error in stderr, because we can't produce a correct kind of
|
||||
// suggestion with current implementation
|
||||
let mut c: (i32, i32) = Default::default();
|
||||
c.0 = 42;
|
||||
c.1 = 21;
|
||||
|
||||
// wrong, produces the fifth error in stderr
|
||||
let mut a: A = Default::default();
|
||||
a.i = Default::default();
|
||||
|
||||
// wrong, produces the sixth error in stderr
|
||||
let mut a: A = Default::default();
|
||||
a.i = Default::default();
|
||||
a.j = 45;
|
||||
|
||||
// right, because an assignment refers to another field
|
||||
let mut x = A::default();
|
||||
x.i = 42;
|
||||
x.j = 21 + x.i as i64;
|
||||
|
||||
// right, we bail out if there's a reassignment to the same variable, since there is a risk of
|
||||
// side-effects affecting the outcome
|
||||
let mut x = A::default();
|
||||
let mut side_effect = SideEffect::new();
|
||||
x.i = side_effect.next();
|
||||
x.j = 2;
|
||||
x.i = side_effect.next();
|
||||
}
|
||||
75
tests/ui/field_reassign_with_default.stderr
Normal file
75
tests/ui/field_reassign_with_default.stderr
Normal file
@ -0,0 +1,75 @@
|
||||
error: field assignment outside of initializer for an instance created with Default::default()
|
||||
--> $DIR/field_reassign_with_default.rs:30:5
|
||||
|
|
||||
LL | a.i = 42;
|
||||
| ^^^^^^^^^
|
||||
|
|
||||
= note: `-D clippy::field-reassign-with-default` implied by `-D warnings`
|
||||
note: consider initializing the variable with `A { i: 42, ..Default::default() }` and removing relevant reassignments
|
||||
--> $DIR/field_reassign_with_default.rs:29:5
|
||||
|
|
||||
LL | let mut a: A = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
error: field assignment outside of initializer for an instance created with Default::default()
|
||||
--> $DIR/field_reassign_with_default.rs:70:5
|
||||
|
|
||||
LL | a.j = 43;
|
||||
| ^^^^^^^^^
|
||||
|
|
||||
note: consider initializing the variable with `A { j: 43, i: 42 }` and removing relevant reassignments
|
||||
--> $DIR/field_reassign_with_default.rs:69:5
|
||||
|
|
||||
LL | let mut a: A = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
error: field assignment outside of initializer for an instance created with Default::default()
|
||||
--> $DIR/field_reassign_with_default.rs:75:5
|
||||
|
|
||||
LL | a.i = 42;
|
||||
| ^^^^^^^^^
|
||||
|
|
||||
note: consider initializing the variable with `A { i: 42, j: 44 }` and removing relevant reassignments
|
||||
--> $DIR/field_reassign_with_default.rs:74:5
|
||||
|
|
||||
LL | let mut a: A = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
error: field assignment outside of initializer for an instance created with Default::default()
|
||||
--> $DIR/field_reassign_with_default.rs:81:5
|
||||
|
|
||||
LL | a.i = 42;
|
||||
| ^^^^^^^^^
|
||||
|
|
||||
note: consider initializing the variable with `A { i: 42, ..Default::default() }` and removing relevant reassignments
|
||||
--> $DIR/field_reassign_with_default.rs:80:5
|
||||
|
|
||||
LL | let mut a = A::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
error: field assignment outside of initializer for an instance created with Default::default()
|
||||
--> $DIR/field_reassign_with_default.rs:91:5
|
||||
|
|
||||
LL | a.i = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
|
||||
note: consider initializing the variable with `A::default()` and removing relevant reassignments
|
||||
--> $DIR/field_reassign_with_default.rs:90:5
|
||||
|
|
||||
LL | let mut a: A = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
error: field assignment outside of initializer for an instance created with Default::default()
|
||||
--> $DIR/field_reassign_with_default.rs:95:5
|
||||
|
|
||||
LL | a.i = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
|
||||
note: consider initializing the variable with `A { j: 45, ..Default::default() }` and removing relevant reassignments
|
||||
--> $DIR/field_reassign_with_default.rs:94:5
|
||||
|
|
||||
LL | let mut a: A = Default::default();
|
||||
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
||||
|
||||
error: aborting due to 6 previous errors
|
||||
|
||||
Loading…
Reference in New Issue
Block a user