diff --git a/clippy_lints/src/write.rs b/clippy_lints/src/write.rs index 210ddc7465ff..e416eab79141 100644 --- a/clippy_lints/src/write.rs +++ b/clippy_lints/src/write.rs @@ -1,10 +1,11 @@ use std::borrow::Cow; -use std::ops::Range; +use std::iter; +use std::ops::{Deref, Range}; use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg, span_lint_and_then}; use clippy_utils::source::{snippet_opt, snippet_with_applicability}; -use rustc_ast::ast::{Expr, ExprKind, ImplKind, Item, ItemKind, LitKind, MacCall, Path, StrLit, StrStyle}; -use rustc_ast::token; +use rustc_ast::ast::{Expr, ExprKind, ImplKind, Item, ItemKind, MacCall, Path, StrLit, StrStyle}; +use rustc_ast::token::{self, LitKind}; use rustc_ast::tokenstream::TokenStream; use rustc_errors::Applicability; use rustc_lexer::unescape::{self, EscapeError}; @@ -438,7 +439,7 @@ impl Write { fn parse_fmt_string(&self, cx: &EarlyContext<'_>, str: &StrLit) -> Option { use rustc_parse_format::{ParseMode, Parser, Piece}; - let str_sym = str.symbol.as_str(); + let str_sym = str.symbol_unescaped.as_str(); let style = match str.style { StrStyle::Cooked => None, StrStyle::Raw(n) => Some(n as usize), @@ -514,21 +515,17 @@ impl Write { if !parser.eat(&token::Comma) { return (Some(fmtstr), expr); } + + let comma_span = parser.prev_token.span; let token_expr = if let Ok(expr) = parser.parse_expr().map_err(|mut err| err.cancel()) { expr } else { return (Some(fmtstr), None); }; - let (fmt_spans, span) = match &token_expr.kind { - ExprKind::Lit(lit) if !matches!(lit.kind, LitKind::Int(..) | LitKind::Float(..)) => { - (unnamed_args.next().unwrap_or(&[]), token_expr.span) - }, + let (fmt_spans, lit) = match &token_expr.kind { + ExprKind::Lit(lit) => (unnamed_args.next().unwrap_or(&[]), lit), ExprKind::Assign(lhs, rhs, _) => match (&lhs.kind, &rhs.kind) { - (ExprKind::Path(_, p), ExprKind::Lit(lit)) - if !matches!(lit.kind, LitKind::Int(..) | LitKind::Float(..)) => - { - (args.get_named(p), rhs.span) - }, + (ExprKind::Path(_, p), ExprKind::Lit(lit)) => (args.get_named(p), lit), _ => continue, }, _ => { @@ -537,8 +534,45 @@ impl Write { }, }; + let replacement: String = match lit.token.kind { + LitKind::Integer | LitKind::Float | LitKind::Err => continue, + LitKind::StrRaw(_) | LitKind::ByteStrRaw(_) if matches!(fmtstr.style, StrStyle::Raw(_)) => { + lit.token.symbol.as_str().replace("{", "{{").replace("}", "}}") + }, + LitKind::Str | LitKind::ByteStr if matches!(fmtstr.style, StrStyle::Cooked) => { + lit.token.symbol.as_str().replace("{", "{{").replace("}", "}}") + }, + LitKind::StrRaw(_) | LitKind::Str | LitKind::ByteStrRaw(_) | LitKind::ByteStr => continue, + LitKind::Byte | LitKind::Char => match lit.token.symbol.as_str().deref() { + "\"" if matches!(fmtstr.style, StrStyle::Cooked) => "\\\"", + "\"" if matches!(fmtstr.style, StrStyle::Raw(0)) => continue, + "\\\\" if matches!(fmtstr.style, StrStyle::Raw(_)) => "\\", + "\\'" => "'", + "{" => "{{", + "}" => "}}", + x if matches!(fmtstr.style, StrStyle::Raw(_)) && x.starts_with("\\") => continue, + x => x, + } + .into(), + LitKind::Bool => lit.token.symbol.as_str().deref().into(), + }; + if !fmt_spans.is_empty() { - span_lint(cx, lint, span, "literal with an empty format string"); + span_lint_and_then( + cx, + lint, + token_expr.span, + "literal with an empty format string", + |diag| { + diag.multipart_suggestion( + "try this", + iter::once((comma_span.to(token_expr.span), String::new())) + .chain(fmt_spans.iter().cloned().zip(iter::repeat(replacement))) + .collect(), + Applicability::MachineApplicable, + ); + }, + ); } } } diff --git a/tests/ui/print_literal.stderr b/tests/ui/print_literal.stderr index e284aece236f..54a4084c89e1 100644 --- a/tests/ui/print_literal.stderr +++ b/tests/ui/print_literal.stderr @@ -5,66 +5,120 @@ LL | print!("Hello {}", "world"); | ^^^^^^^ | = note: `-D clippy::print-literal` implied by `-D warnings` +help: try this + | +LL | print!("Hello world"); + | ^^^^^-- error: literal with an empty format string --> $DIR/print_literal.rs:26:36 | LL | println!("Hello {} {}", world, "world"); | ^^^^^^^ + | +help: try this + | +LL | println!("Hello {} world", world); + | ^^^^^ -- error: literal with an empty format string --> $DIR/print_literal.rs:27:26 | LL | println!("Hello {}", "world"); | ^^^^^^^ + | +help: try this + | +LL | println!("Hello world"); + | ^^^^^-- error: literal with an empty format string --> $DIR/print_literal.rs:32:25 | LL | println!("{0} {1}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | println!("hello {1}", "world"); + | ^^^^^ -- error: literal with an empty format string --> $DIR/print_literal.rs:32:34 | LL | println!("{0} {1}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | println!("{0} world", "hello"); + | ^^^^^ -- error: literal with an empty format string --> $DIR/print_literal.rs:33:25 | LL | println!("{1} {0}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | println!("{1} hello", "world"); + | ^^^^^-- error: literal with an empty format string --> $DIR/print_literal.rs:33:34 | LL | println!("{1} {0}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | println!("world {0}", "hello"); + | ^^^^^ -- error: literal with an empty format string - --> $DIR/print_literal.rs:36:35 + --> $DIR/print_literal.rs:36:29 | LL | println!("{foo} {bar}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | println!("hello {bar}", bar = "world"); + | ^^^^^ -- error: literal with an empty format string - --> $DIR/print_literal.rs:36:50 + --> $DIR/print_literal.rs:36:44 | LL | println!("{foo} {bar}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | println!("{foo} world", foo = "hello"); + | ^^^^^ -- error: literal with an empty format string - --> $DIR/print_literal.rs:37:35 + --> $DIR/print_literal.rs:37:29 | LL | println!("{bar} {foo}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | println!("{bar} hello", bar = "world"); + | ^^^^^-- error: literal with an empty format string - --> $DIR/print_literal.rs:37:50 + --> $DIR/print_literal.rs:37:44 | LL | println!("{bar} {foo}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | println!("world {foo}", foo = "hello"); + | ^^^^^ -- error: aborting due to 11 previous errors diff --git a/tests/ui/write_literal.stderr b/tests/ui/write_literal.stderr index e54d89ecf29e..507a78e82805 100644 --- a/tests/ui/write_literal.stderr +++ b/tests/ui/write_literal.stderr @@ -5,66 +5,120 @@ LL | write!(&mut v, "Hello {}", "world"); | ^^^^^^^ | = note: `-D clippy::write-literal` implied by `-D warnings` +help: try this + | +LL | write!(&mut v, "Hello world"); + | ^^^^^-- error: literal with an empty format string --> $DIR/write_literal.rs:31:44 | LL | writeln!(&mut v, "Hello {} {}", world, "world"); | ^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "Hello {} world", world); + | ^^^^^ -- error: literal with an empty format string --> $DIR/write_literal.rs:32:34 | LL | writeln!(&mut v, "Hello {}", "world"); | ^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "Hello world"); + | ^^^^^-- error: literal with an empty format string --> $DIR/write_literal.rs:37:33 | LL | writeln!(&mut v, "{0} {1}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "hello {1}", "world"); + | ^^^^^ -- error: literal with an empty format string --> $DIR/write_literal.rs:37:42 | LL | writeln!(&mut v, "{0} {1}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "{0} world", "hello"); + | ^^^^^ -- error: literal with an empty format string --> $DIR/write_literal.rs:38:33 | LL | writeln!(&mut v, "{1} {0}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "{1} hello", "world"); + | ^^^^^-- error: literal with an empty format string --> $DIR/write_literal.rs:38:42 | LL | writeln!(&mut v, "{1} {0}", "hello", "world"); | ^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "world {0}", "hello"); + | ^^^^^ -- error: literal with an empty format string - --> $DIR/write_literal.rs:41:43 + --> $DIR/write_literal.rs:41:37 | LL | writeln!(&mut v, "{foo} {bar}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "hello {bar}", bar = "world"); + | ^^^^^ -- error: literal with an empty format string - --> $DIR/write_literal.rs:41:58 + --> $DIR/write_literal.rs:41:52 | LL | writeln!(&mut v, "{foo} {bar}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "{foo} world", foo = "hello"); + | ^^^^^ -- error: literal with an empty format string - --> $DIR/write_literal.rs:42:43 + --> $DIR/write_literal.rs:42:37 | LL | writeln!(&mut v, "{bar} {foo}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "{bar} hello", bar = "world"); + | ^^^^^-- error: literal with an empty format string - --> $DIR/write_literal.rs:42:58 + --> $DIR/write_literal.rs:42:52 | LL | writeln!(&mut v, "{bar} {foo}", foo = "hello", bar = "world"); - | ^^^^^^^ + | ^^^^^^^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, "world {foo}", foo = "hello"); + | ^^^^^ -- error: aborting due to 11 previous errors diff --git a/tests/ui/write_literal_2.rs b/tests/ui/write_literal_2.rs new file mode 100644 index 000000000000..f341e8215e1c --- /dev/null +++ b/tests/ui/write_literal_2.rs @@ -0,0 +1,27 @@ +#![allow(unused_must_use)] +#![warn(clippy::write_literal)] + +use std::io::Write; + +fn main() { + let mut v = Vec::new(); + + writeln!(&mut v, "{}", "{hello}"); + writeln!(&mut v, r"{}", r"{hello}"); + writeln!(&mut v, "{}", '\''); + writeln!(&mut v, "{}", '"'); + writeln!(&mut v, r"{}", '"'); // don't lint + writeln!(&mut v, r"{}", '\''); + writeln!( + &mut v, + "some {}", + "hello \ + world!" + ); + writeln!( + &mut v, + "some {}\ + {} \\ {}", + "1", "2", "3", + ); +} diff --git a/tests/ui/write_literal_2.stderr b/tests/ui/write_literal_2.stderr new file mode 100644 index 000000000000..5b4883580111 --- /dev/null +++ b/tests/ui/write_literal_2.stderr @@ -0,0 +1,106 @@ +error: literal with an empty format string + --> $DIR/write_literal_2.rs:9:28 + | +LL | writeln!(&mut v, "{}", "{hello}"); + | ^^^^^^^^^ + | + = note: `-D clippy::write-literal` implied by `-D warnings` +help: try this + | +LL | writeln!(&mut v, "{{hello}}"); + | ^^^^^^^^^-- + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:10:29 + | +LL | writeln!(&mut v, r"{}", r"{hello}"); + | ^^^^^^^^^^ + | +help: try this + | +LL | writeln!(&mut v, r"{{hello}}"); + | ^^^^^^^^^-- + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:11:28 + | +LL | writeln!(&mut v, "{}", '/''); + | ^^^^ + | +help: try this + | +LL | writeln!(&mut v, "'"); + | ^-- + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:12:28 + | +LL | writeln!(&mut v, "{}", '"'); + | ^^^ + | +help: try this + | +LL | writeln!(&mut v, "/""); + | ^^-- + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:14:29 + | +LL | writeln!(&mut v, r"{}", '/''); + | ^^^^ + | +help: try this + | +LL | writeln!(&mut v, r"'"); + | ^-- + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:18:9 + | +LL | / "hello / +LL | | world!" + | |_______________^ + | +help: try this + | +LL | "some hello / +LL | world!" + | + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:25:9 + | +LL | "1", "2", "3", + | ^^^ + | +help: try this + | +LL | "some 1{} / {}", "2", "3", + | ^ -- + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:25:14 + | +LL | "1", "2", "3", + | ^^^ + | +help: try this + | +LL | 2 / {}", +LL | "1", "3", + | + +error: literal with an empty format string + --> $DIR/write_literal_2.rs:25:19 + | +LL | "1", "2", "3", + | ^^^ + | +help: try this + | +LL | {} / 3", +LL | "1", "2", + | + +error: aborting due to 9 previous errors +