//! This module contains functions for retrieve the original AST from lowered
//! `hir`.
-#![deny(missing_docs_in_private_items)]
+#![deny(clippy::missing_docs_in_private_items)]
-use rustc::hir;
+use crate::utils::{is_expn_of, match_def_path, match_qpath, opt_def_id, paths, resolve_node};
+use if_chain::if_chain;
use rustc::lint::LateContext;
+use rustc::{hir, ty};
use syntax::ast;
-use utils::{is_expn_of, match_qpath, match_def_path, resolve_node, paths};
/// Convert a hir binary operator to the corresponding `ast` type.
-pub fn binop(op: hir::BinOp_) -> ast::BinOpKind {
+pub fn binop(op: hir::BinOpKind) -> ast::BinOpKind {
match op {
- hir::BiEq => ast::BinOpKind::Eq,
- hir::BiGe => ast::BinOpKind::Ge,
- hir::BiGt => ast::BinOpKind::Gt,
- hir::BiLe => ast::BinOpKind::Le,
- hir::BiLt => ast::BinOpKind::Lt,
- hir::BiNe => ast::BinOpKind::Ne,
- hir::BiOr => ast::BinOpKind::Or,
- hir::BiAdd => ast::BinOpKind::Add,
- hir::BiAnd => ast::BinOpKind::And,
- hir::BiBitAnd => ast::BinOpKind::BitAnd,
- hir::BiBitOr => ast::BinOpKind::BitOr,
- hir::BiBitXor => ast::BinOpKind::BitXor,
- hir::BiDiv => ast::BinOpKind::Div,
- hir::BiMul => ast::BinOpKind::Mul,
- hir::BiRem => ast::BinOpKind::Rem,
- hir::BiShl => ast::BinOpKind::Shl,
- hir::BiShr => ast::BinOpKind::Shr,
- hir::BiSub => ast::BinOpKind::Sub,
+ hir::BinOpKind::Eq => ast::BinOpKind::Eq,
+ hir::BinOpKind::Ge => ast::BinOpKind::Ge,
+ hir::BinOpKind::Gt => ast::BinOpKind::Gt,
+ hir::BinOpKind::Le => ast::BinOpKind::Le,
+ hir::BinOpKind::Lt => ast::BinOpKind::Lt,
+ hir::BinOpKind::Ne => ast::BinOpKind::Ne,
+ hir::BinOpKind::Or => ast::BinOpKind::Or,
+ hir::BinOpKind::Add => ast::BinOpKind::Add,
+ hir::BinOpKind::And => ast::BinOpKind::And,
+ hir::BinOpKind::BitAnd => ast::BinOpKind::BitAnd,
+ hir::BinOpKind::BitOr => ast::BinOpKind::BitOr,
+ hir::BinOpKind::BitXor => ast::BinOpKind::BitXor,
+ hir::BinOpKind::Div => ast::BinOpKind::Div,
+ hir::BinOpKind::Mul => ast::BinOpKind::Mul,
+ hir::BinOpKind::Rem => ast::BinOpKind::Rem,
+ hir::BinOpKind::Shl => ast::BinOpKind::Shl,
+ hir::BinOpKind::Shr => ast::BinOpKind::Shr,
+ hir::BinOpKind::Sub => ast::BinOpKind::Sub,
}
}
}
/// Higher a `hir` range to something similar to `ast::ExprKind::Range`.
-pub fn range(expr: &hir::Expr) -> Option<Range> {
+pub fn range<'a, 'b, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'b hir::Expr) -> Option<Range<'b>> {
/// Find the field named `name` in the field. Always return `Some` for
/// convenience.
fn get_field<'a>(name: &str, fields: &'a [hir::Field]) -> Option<&'a hir::Expr> {
- let expr = &fields
- .iter()
- .find(|field| field.name.node == name)
- .unwrap_or_else(|| panic!("missing {} field for range", name))
- .expr;
+ let expr = &fields.iter().find(|field| field.ident.name == name)?.expr;
Some(expr)
}
+ let def_path = match cx.tables.expr_ty(expr).sty {
+ ty::Adt(def, _) => cx.tcx.def_path(def.did),
+ _ => return None,
+ };
+
+ // sanity checks for std::ops::RangeXXXX
+ if def_path.data.len() != 3 {
+ return None;
+ }
+ if def_path.data.get(0)?.data.as_interned_str() != "ops" {
+ return None;
+ }
+ if def_path.data.get(1)?.data.as_interned_str() != "range" {
+ return None;
+ }
+ let type_name = def_path.data.get(2)?.data.as_interned_str();
+ let range_types = [
+ "RangeFrom",
+ "RangeFull",
+ "RangeInclusive",
+ "Range",
+ "RangeTo",
+ "RangeToInclusive",
+ ];
+ if !range_types.contains(&&*type_name.as_str()) {
+ return None;
+ }
+
// The range syntax is expanded to literal paths starting with `core` or `std`
// depending on
// `#[no_std]`. Testing both instead of resolving the paths.
match expr.node {
- hir::ExprPath(ref path) => {
+ hir::ExprKind::Path(ref path) => {
if match_qpath(path, &paths::RANGE_FULL_STD) || match_qpath(path, &paths::RANGE_FULL) {
Some(Range {
start: None,
None
}
},
- hir::ExprStruct(ref path, ref fields, None) => {
+ hir::ExprKind::Call(ref path, ref args) => {
+ if let hir::ExprKind::Path(ref path) = path.node {
+ if match_qpath(path, &paths::RANGE_INCLUSIVE_STD_NEW) || match_qpath(path, &paths::RANGE_INCLUSIVE_NEW)
+ {
+ Some(Range {
+ start: Some(&args[0]),
+ end: Some(&args[1]),
+ limits: ast::RangeLimits::Closed,
+ })
+ } else {
+ None
+ }
+ } else {
+ None
+ }
+ },
+ hir::ExprKind::Struct(ref path, ref fields, None) => {
if match_qpath(path, &paths::RANGE_FROM_STD) || match_qpath(path, &paths::RANGE_FROM) {
Some(Range {
- start: get_field("start", fields),
+ start: Some(get_field("start", fields)?),
end: None,
limits: ast::RangeLimits::HalfOpen,
})
- } else if match_qpath(path, &paths::RANGE_INCLUSIVE_STD) || match_qpath(path, &paths::RANGE_INCLUSIVE) {
- Some(Range {
- start: get_field("start", fields),
- end: get_field("end", fields),
- limits: ast::RangeLimits::Closed,
- })
} else if match_qpath(path, &paths::RANGE_STD) || match_qpath(path, &paths::RANGE) {
Some(Range {
- start: get_field("start", fields),
- end: get_field("end", fields),
+ start: Some(get_field("start", fields)?),
+ end: Some(get_field("end", fields)?),
limits: ast::RangeLimits::HalfOpen,
})
- } else if match_qpath(path, &paths::RANGE_TO_INCLUSIVE_STD) || match_qpath(path, &paths::RANGE_TO_INCLUSIVE) {
+ } else if match_qpath(path, &paths::RANGE_TO_INCLUSIVE_STD) || match_qpath(path, &paths::RANGE_TO_INCLUSIVE)
+ {
Some(Range {
start: None,
- end: get_field("end", fields),
+ end: Some(get_field("end", fields)?),
limits: ast::RangeLimits::Closed,
})
} else if match_qpath(path, &paths::RANGE_TO_STD) || match_qpath(path, &paths::RANGE_TO) {
Some(Range {
start: None,
- end: get_field("end", fields),
+ end: Some(get_field("end", fields)?),
limits: ast::RangeLimits::HalfOpen,
})
} else {
}
}
-/// Checks if a `let` decl is from a `for` loop desugaring.
-pub fn is_from_for_desugar(decl: &hir::Decl) -> bool {
+/// Checks if a `let` statement is from a `for` loop desugaring.
+pub fn is_from_for_desugar(local: &hir::Local) -> bool {
// This will detect plain for-loops without an actual variable binding:
//
// ```
// for x in some_vec {
- // // do stuff
+ // // do stuff
// }
// ```
- if_let_chain! {[
- let hir::DeclLocal(ref loc) = decl.node,
- let Some(ref expr) = loc.init,
- let hir::ExprMatch(_, _, hir::MatchSource::ForLoopDesugar) = expr.node,
- ], {
- return true;
- }}
+ if_chain! {
+ if let Some(ref expr) = local.init;
+ if let hir::ExprKind::Match(_, _, hir::MatchSource::ForLoopDesugar) = expr.node;
+ then {
+ return true;
+ }
+ }
// This detects a variable binding in for loop to avoid `let_unit_value`
// lint (see issue #1964).
//
// ```
// for _ in vec![()] {
- // // anything
+ // // anything
// }
// ```
- if_let_chain! {[
- let hir::DeclLocal(ref loc) = decl.node,
- let hir::LocalSource::ForLoopDesugar = loc.source,
- ], {
+ if let hir::LocalSource::ForLoopDesugar = local.source {
return true;
- }}
+ }
false
}
/// Recover the essential nodes of a desugared for loop:
/// `for pat in arg { body }` becomes `(pat, arg, body)`.
pub fn for_loop(expr: &hir::Expr) -> Option<(&hir::Pat, &hir::Expr, &hir::Expr)> {
- if_let_chain! {[
- let hir::ExprMatch(ref iterexpr, ref arms, hir::MatchSource::ForLoopDesugar) = expr.node,
- let hir::ExprCall(_, ref iterargs) = iterexpr.node,
- iterargs.len() == 1 && arms.len() == 1 && arms[0].guard.is_none(),
- let hir::ExprLoop(ref block, _, _) = arms[0].body.node,
- block.expr.is_none(),
- let [ _, _, ref let_stmt, ref body ] = *block.stmts,
- let hir::StmtDecl(ref decl, _) = let_stmt.node,
- let hir::DeclLocal(ref decl) = decl.node,
- let hir::StmtExpr(ref expr, _) = body.node,
- ], {
- return Some((&*decl.pat, &iterargs[0], expr));
- }}
+ if_chain! {
+ if let hir::ExprKind::Match(ref iterexpr, ref arms, hir::MatchSource::ForLoopDesugar) = expr.node;
+ if let hir::ExprKind::Call(_, ref iterargs) = iterexpr.node;
+ if iterargs.len() == 1 && arms.len() == 1 && arms[0].guard.is_none();
+ if let hir::ExprKind::Loop(ref block, _, _) = arms[0].body.node;
+ if block.expr.is_none();
+ if let [ _, _, ref let_stmt, ref body ] = *block.stmts;
+ if let hir::StmtKind::Local(ref local) = let_stmt.node;
+ if let hir::StmtKind::Expr(ref expr) = body.node;
+ then {
+ return Some((&*local.pat, &iterargs[0], expr));
+ }
+ }
None
}
/// Returns the arguments of the `vec!` macro if this expression was expanded
/// from `vec!`.
-pub fn vec_macro<'e>(cx: &LateContext, expr: &'e hir::Expr) -> Option<VecArgs<'e>> {
- if_let_chain!{[
- let hir::ExprCall(ref fun, ref args) = expr.node,
- let hir::ExprPath(ref path) = fun.node,
- is_expn_of(fun.span, "vec").is_some(),
- ], {
- let fun_def = resolve_node(cx, path, fun.hir_id);
- return if match_def_path(cx.tcx, fun_def.def_id(), &paths::VEC_FROM_ELEM) && args.len() == 2 {
- // `vec![elem; size]` case
- Some(VecArgs::Repeat(&args[0], &args[1]))
- }
- else if match_def_path(cx.tcx, fun_def.def_id(), &paths::SLICE_INTO_VEC) && args.len() == 1 {
- // `vec![a, b, c]` case
- if_let_chain!{[
- let hir::ExprBox(ref boxed) = args[0].node,
- let hir::ExprArray(ref args) = boxed.node
- ], {
- return Some(VecArgs::Vec(&*args));
- }}
-
- None
+pub fn vec_macro<'e>(cx: &LateContext<'_, '_>, expr: &'e hir::Expr) -> Option<VecArgs<'e>> {
+ if_chain! {
+ if let hir::ExprKind::Call(ref fun, ref args) = expr.node;
+ if let hir::ExprKind::Path(ref path) = fun.node;
+ if is_expn_of(fun.span, "vec").is_some();
+ if let Some(fun_def_id) = opt_def_id(resolve_node(cx, path, fun.hir_id));
+ then {
+ return if match_def_path(cx.tcx, fun_def_id, &paths::VEC_FROM_ELEM) && args.len() == 2 {
+ // `vec![elem; size]` case
+ Some(VecArgs::Repeat(&args[0], &args[1]))
+ }
+ else if match_def_path(cx.tcx, fun_def_id, &paths::SLICE_INTO_VEC) && args.len() == 1 {
+ // `vec![a, b, c]` case
+ if_chain! {
+ if let hir::ExprKind::Box(ref boxed) = args[0].node;
+ if let hir::ExprKind::Array(ref args) = boxed.node;
+ then {
+ return Some(VecArgs::Vec(&*args));
+ }
+ }
+
+ None
+ }
+ else {
+ None
+ };
}
- else {
- None
- };
- }}
+ }
None
}
projects / rust.git / blobdiff