mod returns;
mod serde_api;
mod shadow;
-mod single_char_push_str;
mod single_component_path_imports;
mod slow_vector_initialization;
mod stable_sort_primitive;
&methods::SEARCH_IS_SOME,
&methods::SHOULD_IMPLEMENT_TRAIT,
&methods::SINGLE_CHAR_PATTERN,
+ &methods::SINGLE_CHAR_PUSH_STR,
&methods::SKIP_WHILE_NEXT,
&methods::STRING_EXTEND_CHARS,
&methods::SUSPICIOUS_MAP,
&shadow::SHADOW_REUSE,
&shadow::SHADOW_SAME,
&shadow::SHADOW_UNRELATED,
- &single_char_push_str::SINGLE_CHAR_PUSH_STR,
&single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS,
&slow_vector_initialization::SLOW_VECTOR_INITIALIZATION,
&stable_sort_primitive::STABLE_SORT_PRIMITIVE,
store.register_late_pass(move || box escape::BoxedLocal{too_large_for_stack});
store.register_late_pass(|| box panic_unimplemented::PanicUnimplemented);
store.register_late_pass(|| box strings::StringLitAsBytes);
- store.register_late_pass(|| box single_char_push_str::SingleCharPushStrPass);
store.register_late_pass(|| box derive::Derive);
store.register_late_pass(|| box types::CharLitAsU8);
store.register_late_pass(|| box vec::UselessVec);
LintId::of(&methods::SEARCH_IS_SOME),
LintId::of(&methods::SHOULD_IMPLEMENT_TRAIT),
LintId::of(&methods::SINGLE_CHAR_PATTERN),
+ LintId::of(&methods::SINGLE_CHAR_PUSH_STR),
LintId::of(&methods::SKIP_WHILE_NEXT),
LintId::of(&methods::STRING_EXTEND_CHARS),
LintId::of(&methods::SUSPICIOUS_MAP),
LintId::of(&returns::NEEDLESS_RETURN),
LintId::of(&returns::UNUSED_UNIT),
LintId::of(&serde_api::SERDE_API_MISUSE),
- LintId::of(&single_char_push_str::SINGLE_CHAR_PUSH_STR),
LintId::of(&single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS),
LintId::of(&slow_vector_initialization::SLOW_VECTOR_INITIALIZATION),
LintId::of(&stable_sort_primitive::STABLE_SORT_PRIMITIVE),
LintId::of(&methods::OPTION_MAP_OR_NONE),
LintId::of(&methods::RESULT_MAP_OR_INTO_OPTION),
LintId::of(&methods::SHOULD_IMPLEMENT_TRAIT),
+ LintId::of(&methods::SINGLE_CHAR_PUSH_STR),
LintId::of(&methods::STRING_EXTEND_CHARS),
LintId::of(&methods::UNNECESSARY_FOLD),
LintId::of(&methods::WRONG_SELF_CONVENTION),
LintId::of(®ex::TRIVIAL_REGEX),
LintId::of(&returns::NEEDLESS_RETURN),
LintId::of(&returns::UNUSED_UNIT),
- LintId::of(&single_char_push_str::SINGLE_CHAR_PUSH_STR),
LintId::of(&single_component_path_imports::SINGLE_COMPONENT_PATH_IMPORTS),
LintId::of(&strings::STRING_LIT_AS_BYTES),
LintId::of(&tabs_in_doc_comments::TABS_IN_DOC_COMMENTS),
"using `.iter().next()` on a sliced array, which can be shortened to just `.get()`"
}
+declare_clippy_lint! {
+ /// **What it does:** Warns when using push_str with a single-character string literal,
+ /// and push with a char would work fine.
+ ///
+ /// **Why is this bad?** it's less clear that we are pushing a single character
+ ///
+ /// **Known problems:** None
+ ///
+ /// **Example:**
+ /// ```
+ /// let mut string = String::new();
+ /// string.push_str("R");
+ /// ```
+ /// Could be written as
+ /// ```
+ /// let mut string = String::new();
+ /// string.push('R');
+ /// ```
+ pub SINGLE_CHAR_PUSH_STR,
+ style,
+ "`push_str()` used with a single-character string literal as parameter"
+}
+
declare_lint_pass!(Methods => [
UNWRAP_USED,
EXPECT_USED,
INEFFICIENT_TO_STRING,
NEW_RET_NO_SELF,
SINGLE_CHAR_PATTERN,
+ SINGLE_CHAR_PUSH_STR,
SEARCH_IS_SOME,
TEMPORARY_CSTRING_AS_PTR,
FILTER_NEXT,
inefficient_to_string::lint(cx, expr, &args[0], self_ty);
}
+ if let Some(fn_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id) {
+ if match_def_path(cx, fn_def_id, &paths::PUSH_STR) {
+ lint_single_char_push_string(cx, expr, args);
+ }
+ }
+
match self_ty.kind {
ty::Ref(_, ty, _) if ty.kind == ty::Str => {
for &(method, pos) in &PATTERN_METHODS {
}
}
-/// lint for length-1 `str`s for methods in `PATTERN_METHODS`
-fn lint_single_char_pattern<'tcx>(cx: &LateContext<'tcx>, _expr: &'tcx hir::Expr<'_>, arg: &'tcx hir::Expr<'_>) {
+fn get_hint_if_single_char_arg<'tcx>(
+ cx: &LateContext<'tcx>,
+ arg: &'tcx hir::Expr<'_>,
+ applicability: &mut Applicability,
+) -> Option<String> {
if_chain! {
if let hir::ExprKind::Lit(lit) = &arg.kind;
if let ast::LitKind::Str(r, style) = lit.node;
- if r.as_str().len() == 1;
+ let string = r.as_str();
+ if string.len() == 1;
then {
- let mut applicability = Applicability::MachineApplicable;
- let snip = snippet_with_applicability(cx, arg.span, "..", &mut applicability);
+ let snip = snippet_with_applicability(cx, arg.span, &string, applicability);
let ch = if let ast::StrStyle::Raw(nhash) = style {
let nhash = nhash as usize;
// for raw string: r##"a"##
&snip[1..(snip.len() - 1)]
};
let hint = format!("'{}'", if ch == "'" { "\\'" } else { ch });
- span_lint_and_sugg(
- cx,
- SINGLE_CHAR_PATTERN,
- arg.span,
- "single-character string constant used as pattern",
- "try using a `char` instead",
- hint,
- applicability,
- );
+ Some(hint)
+ } else {
+ None
}
}
}
+/// lint for length-1 `str`s for methods in `PATTERN_METHODS`
+fn lint_single_char_pattern<'tcx>(cx: &LateContext<'tcx>, _expr: &'tcx hir::Expr<'_>, arg: &'tcx hir::Expr<'_>) {
+ let mut applicability = Applicability::MachineApplicable;
+ if let Some(hint) = get_hint_if_single_char_arg(cx, arg, &mut applicability) {
+ span_lint_and_sugg(
+ cx,
+ SINGLE_CHAR_PATTERN,
+ arg.span,
+ "single-character string constant used as pattern",
+ "try using a `char` instead",
+ hint,
+ applicability,
+ );
+ }
+}
+
+/// lint for length-1 `str`s as argument for `push_str`
+fn lint_single_char_push_string<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>, args: &'tcx [hir::Expr<'_>]) {
+ let mut applicability = Applicability::MachineApplicable;
+ if let Some(extension_string) = get_hint_if_single_char_arg(cx, &args[1], &mut applicability) {
+ let base_string_snippet = snippet_with_applicability(cx, args[0].span, "_", &mut applicability);
+ let sugg = format!("{}.push({})", base_string_snippet, extension_string);
+ span_lint_and_sugg(
+ cx,
+ SINGLE_CHAR_PUSH_STR,
+ expr.span,
+ "calling `push_str()` using a single-character string literal",
+ "consider using `push` with a character literal",
+ sugg,
+ applicability,
+ );
+ }
+}
+
/// Checks for the `USELESS_ASREF` lint.
fn lint_asref(cx: &LateContext<'_>, expr: &hir::Expr<'_>, call_name: &str, as_ref_args: &[hir::Expr<'_>]) {
// when we get here, we've already checked that the call name is "as_ref" or "as_mut"
+++ /dev/null
-use crate::utils::{match_def_path, paths, snippet_with_applicability, span_lint_and_sugg};
-use if_chain::if_chain;
-use rustc_ast::ast::LitKind;
-use rustc_errors::Applicability;
-use rustc_hir::{Expr, ExprKind};
-use rustc_lint::{LateContext, LateLintPass};
-use rustc_session::{declare_lint_pass, declare_tool_lint};
-
-declare_clippy_lint! {
- /// **What it does:** Warns when using push_str with a single-character string literal,
- /// and push with a char would work fine.
- ///
- /// **Why is this bad?** This is in all probability not the intended outcome. At
- /// the least it hurts readability of the code.
- ///
- /// **Known problems:** None
- ///
- /// **Example:**
- /// ```
- /// let mut string = String::new();
- /// string.push_str("R");
- /// ```
- /// Could be written as
- /// ```
- /// let mut string = String::new();
- /// string.push('R');
- /// ```
- pub SINGLE_CHAR_PUSH_STR,
- style,
- "`push_str()` used with a single-character string literal as parameter"
-}
-
-declare_lint_pass!(SingleCharPushStrPass => [SINGLE_CHAR_PUSH_STR]);
-
-impl<'tcx> LateLintPass<'tcx> for SingleCharPushStrPass {
- fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
- if_chain! {
- if let ExprKind::MethodCall(_, _, ref args, _) = expr.kind;
- if let [base_string, extension_string] = args;
- if let Some(fn_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id);
- if match_def_path(cx, fn_def_id, &paths::PUSH_STR);
- if let ExprKind::Lit(ref lit) = extension_string.kind;
- if let LitKind::Str(symbol,_) = lit.node;
- let extension_string_val = symbol.as_str().to_string();
- if extension_string_val.len() == 1;
- then {
- let mut applicability = Applicability::MachineApplicable;
- let base_string_snippet = snippet_with_applicability(cx, base_string.span, "_", &mut applicability);
- let sugg = format!("{}.push({:?})", base_string_snippet, extension_string_val.chars().next().unwrap());
- span_lint_and_sugg(
- cx,
- SINGLE_CHAR_PUSH_STR,
- expr.span,
- "calling `push_str()` using a single-character string literal",
- "consider using `push` with a character literal",
- sugg,
- applicability
- );
- }
- }
- }
-}
group: "style",
desc: "`push_str()` used with a single-character string literal as parameter",
deprecation: None,
- module: "single_char_push_str",
+ module: "methods",
},
Lint {
name: "single_component_path_imports",
string.push('\'');
string.push('u');
+ string.push_str("st");
+ string.push_str("");
+ string.push('\x52');
+ string.push('\u{0052}');
+ string.push('a');
}
string.push_str("'");
string.push('u');
+ string.push_str("st");
+ string.push_str("");
+ string.push_str("\x52");
+ string.push_str("\u{0052}");
+ string.push_str(r##"a"##);
}
LL | string.push_str("'");
| ^^^^^^^^^^^^^^^^^^^^ help: consider using `push` with a character literal: `string.push('/'')`
-error: aborting due to 2 previous errors
+error: calling `push_str()` using a single-character string literal
+ --> $DIR/single_char_push_str.rs:12:5
+ |
+LL | string.push_str("/x52");
+ | ^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `push` with a character literal: `string.push('/x52')`
+
+error: calling `push_str()` using a single-character string literal
+ --> $DIR/single_char_push_str.rs:13:5
+ |
+LL | string.push_str("/u{0052}");
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `push` with a character literal: `string.push('/u{0052}')`
+
+error: calling `push_str()` using a single-character string literal
+ --> $DIR/single_char_push_str.rs:14:5
+ |
+LL | string.push_str(r##"a"##);
+ | ^^^^^^^^^^^^^^^^^^^^^^^^^ help: consider using `push` with a character literal: `string.push('a')`
+
+error: aborting due to 5 previous errors
projects / rust.git / commitdiff