From d504290839c2c6736b9a6d1f97ac8f4d48467341 Mon Sep 17 00:00:00 2001 From: Michael Recachinas Date: Mon, 2 Apr 2018 20:32:46 +0100 Subject: [PATCH] Add edge case with env! arg to test and known problems --- clippy_lints/src/print.rs | 3 ++ tests/ui/print_literal.rs | 6 +++ tests/ui/print_literal.stderr | 74 +++++++++++++++++++---------------- 3 files changed, 49 insertions(+), 34 deletions(-) diff --git a/clippy_lints/src/print.rs b/clippy_lints/src/print.rs index 5dce94a72..ddfe6d68f 100644 --- a/clippy_lints/src/print.rs +++ b/clippy_lints/src/print.rs @@ -84,6 +84,9 @@ declare_clippy_lint! { /// (c.f., https://github.com/matthiaskrgr/rust-str-bench) and unnecessary /// (i.e., just put the literal in the format string) /// +/// **Known problems:** Will also warn with macro calls as arguments that expand to literals +/// -- e.g., `println!("{}", env!("FOO"))`. +/// /// **Example:** /// ```rust /// println!("{}", "foo"); diff --git a/tests/ui/print_literal.rs b/tests/ui/print_literal.rs index c803294ab..d920e6fa3 100644 --- a/tests/ui/print_literal.rs +++ b/tests/ui/print_literal.rs @@ -10,6 +10,12 @@ fn main() { println!("Hello {}", world); println!("3 in hex is {:X}", 3); + // this in theory shouldn't yield a warning, + // but at present time, it's a known edge case + // that isn't handled (because we can't expand + // `println!` and not `env!`) + println!("foo: {}", env!("BAR")); + // these should throw warnings print!("Hello {}", "world"); println!("Hello {} {}", world, "world"); diff --git a/tests/ui/print_literal.stderr b/tests/ui/print_literal.stderr index 982be7dc5..8adeedfc8 100644 --- a/tests/ui/print_literal.stderr +++ b/tests/ui/print_literal.stderr @@ -1,100 +1,106 @@ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:14:24 + --> $DIR/print_literal.rs:17:25 | -14 | print!("Hello {}", "world"); - | ^^^^^^^ +17 | println!("foo: {}", env!("BAR")); + | ^^^^^^^^^^^ | = note: `-D print-literal` implied by `-D warnings` error: printing a literal with an empty format string - --> $DIR/print_literal.rs:15:36 + --> $DIR/print_literal.rs:20:24 | -15 | println!("Hello {} {}", world, "world"); +20 | print!("Hello {}", "world"); + | ^^^^^^^ + +error: printing a literal with an empty format string + --> $DIR/print_literal.rs:21:36 + | +21 | println!("Hello {} {}", world, "world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:16:26 + --> $DIR/print_literal.rs:22:26 | -16 | println!("Hello {}", "world"); +22 | println!("Hello {}", "world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:17:30 + --> $DIR/print_literal.rs:23:30 | -17 | println!("10 / 4 is {}", 2.5); +23 | println!("10 / 4 is {}", 2.5); | ^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:18:28 + --> $DIR/print_literal.rs:24:28 | -18 | println!("2 + 1 = {}", 3); +24 | println!("2 + 1 = {}", 3); | ^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:19:31 + --> $DIR/print_literal.rs:25:31 | -19 | println!("2 + 1 = {:.4}", 3); +25 | println!("2 + 1 = {:.4}", 3); | ^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:20:32 + --> $DIR/print_literal.rs:26:32 | -20 | println!("2 + 1 = {:5.4}", 3); +26 | println!("2 + 1 = {:5.4}", 3); | ^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:21:33 + --> $DIR/print_literal.rs:27:33 | -21 | println!("Debug test {:?}", "hello, world"); +27 | println!("Debug test {:?}", "hello, world"); | ^^^^^^^^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:26:25 + --> $DIR/print_literal.rs:32:25 | -26 | println!("{0} {1}", "hello", "world"); +32 | println!("{0} {1}", "hello", "world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:26:34 + --> $DIR/print_literal.rs:32:34 | -26 | println!("{0} {1}", "hello", "world"); +32 | println!("{0} {1}", "hello", "world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:27:25 + --> $DIR/print_literal.rs:33:25 | -27 | println!("{1} {0}", "hello", "world"); +33 | println!("{1} {0}", "hello", "world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:27:34 + --> $DIR/print_literal.rs:33:34 | -27 | println!("{1} {0}", "hello", "world"); +33 | println!("{1} {0}", "hello", "world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:30:33 + --> $DIR/print_literal.rs:36:33 | -30 | println!("{foo} {bar}", foo="hello", bar="world"); +36 | println!("{foo} {bar}", foo="hello", bar="world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:30:46 + --> $DIR/print_literal.rs:36:46 | -30 | println!("{foo} {bar}", foo="hello", bar="world"); +36 | println!("{foo} {bar}", foo="hello", bar="world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:31:33 + --> $DIR/print_literal.rs:37:33 | -31 | println!("{bar} {foo}", foo="hello", bar="world"); +37 | println!("{bar} {foo}", foo="hello", bar="world"); | ^^^^^^^ error: printing a literal with an empty format string - --> $DIR/print_literal.rs:31:46 + --> $DIR/print_literal.rs:37:46 | -31 | println!("{bar} {foo}", foo="hello", bar="world"); +37 | println!("{bar} {foo}", foo="hello", bar="world"); | ^^^^^^^ -error: aborting due to 16 previous errors +error: aborting due to 17 previous errors