use rustc::lint::*;
+use rustc::{declare_lint, lint_array};
use rustc::hir;
-use utils::{span_lint, match_path, match_trait_method, is_try, paths};
+use crate::utils::{is_try, match_qpath, match_trait_method, paths, span_lint};
/// **What it does:** Checks for unused written/read amount.
///
-/// **Why is this bad?** `io::Write::write` and `io::Read::read` are not guaranteed to
-/// process the entire buffer. They return how many bytes were processed, which might be smaller
-/// than a given buffer's length. If you don't need to deal with partial-write/read, use
+/// **Why is this bad?** `io::Write::write` and `io::Read::read` are not
+/// guaranteed to
+/// process the entire buffer. They return how many bytes were processed, which
+/// might be smaller
+/// than a given buffer's length. If you don't need to deal with
+/// partial-write/read, use
/// `write_all`/`read_exact` instead.
///
/// **Known problems:** Detects only common patterns.
/// Ok(())
/// }
/// ```
-declare_lint! {
+declare_clippy_lint! {
pub UNUSED_IO_AMOUNT,
- Deny,
+ correctness,
"unused written/read amount"
}
impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnusedIoAmount {
fn check_stmt(&mut self, cx: &LateContext, s: &hir::Stmt) {
let expr = match s.node {
- hir::StmtSemi(ref expr, _) |
- hir::StmtExpr(ref expr, _) => &**expr,
+ hir::StmtKind::Semi(ref expr, _) | hir::StmtKind::Expr(ref expr, _) => &**expr,
_ => return,
};
match expr.node {
- hir::ExprMatch(ref res, _, _) if is_try(expr).is_some() => {
- if let hir::ExprCall(ref func, ref args) = res.node {
- if let hir::ExprPath(ref path) = func.node {
- if match_path(path, &paths::TRY_INTO_RESULT) && args.len() == 1 {
+ hir::ExprKind::Match(ref res, _, _) if is_try(expr).is_some() => {
+ if let hir::ExprKind::Call(ref func, ref args) = res.node {
+ if let hir::ExprKind::Path(ref path) = func.node {
+ if match_qpath(path, &paths::TRY_INTO_RESULT) && args.len() == 1 {
check_method_call(cx, &args[0], expr);
}
}
}
},
- hir::ExprMethodCall(ref symbol, _, ref args) => {
- match &*symbol.node.as_str() {
- "expect" | "unwrap" | "unwrap_or" | "unwrap_or_else" => {
- check_method_call(cx, &args[0], expr);
- },
- _ => (),
- }
+ hir::ExprKind::MethodCall(ref path, _, ref args) => match &*path.ident.as_str() {
+ "expect" | "unwrap" | "unwrap_or" | "unwrap_or_else" => {
+ check_method_call(cx, &args[0], expr);
+ },
+ _ => (),
},
_ => (),
}
fn check_method_call(cx: &LateContext, call: &hir::Expr, expr: &hir::Expr) {
- if let hir::ExprMethodCall(ref symbol, _, _) = call.node {
- let symbol = &*symbol.node.as_str();
+ if let hir::ExprKind::MethodCall(ref path, _, _) = call.node {
+ let symbol = &*path.ident.as_str();
if match_trait_method(cx, call, &paths::IO_READ) && symbol == "read" {
- span_lint(cx,
- UNUSED_IO_AMOUNT,
- expr.span,
- "handle read amount returned or use `Read::read_exact` instead");
+ span_lint(
+ cx,
+ UNUSED_IO_AMOUNT,
+ expr.span,
+ "handle read amount returned or use `Read::read_exact` instead",
+ );
} else if match_trait_method(cx, call, &paths::IO_WRITE) && symbol == "write" {
- span_lint(cx,
- UNUSED_IO_AMOUNT,
- expr.span,
- "handle written amount returned or use `Write::write_all` instead");
+ span_lint(
+ cx,
+ UNUSED_IO_AMOUNT,
+ expr.span,
+ "handle written amount returned or use `Write::write_all` instead",
+ );
}
}
}