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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /src/tools/clippy/tests/ui/format.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/tools/clippy/tests/ui/format.rs')
-rw-r--r--src/tools/clippy/tests/ui/format.rs96
1 files changed, 96 insertions, 0 deletions
diff --git a/src/tools/clippy/tests/ui/format.rs b/src/tools/clippy/tests/ui/format.rs
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+++ b/src/tools/clippy/tests/ui/format.rs
@@ -0,0 +1,96 @@
+// run-rustfix
+
+#![allow(
+ unused_tuple_struct_fields,
+ clippy::print_literal,
+ clippy::redundant_clone,
+ clippy::to_string_in_format_args,
+ clippy::needless_borrow
+)]
+#![warn(clippy::useless_format)]
+
+struct Foo(pub String);
+
+macro_rules! foo {
+ ($($t:tt)*) => (Foo(format!($($t)*)))
+}
+
+fn main() {
+ format!("foo");
+ format!("{{}}");
+ format!("{{}} abc {{}}");
+ format!(
+ r##"foo {{}}
+" bar"##
+ );
+
+ let _ = format!("");
+
+ format!("{}", "foo");
+ format!("{:?}", "foo"); // Don't warn about `Debug`.
+ format!("{:8}", "foo");
+ format!("{:width$}", "foo", width = 8);
+ format!("{:+}", "foo"); // Warn when the format makes no difference.
+ format!("{:<}", "foo"); // Warn when the format makes no difference.
+ format!("foo {}", "bar");
+ format!("{} bar", "foo");
+
+ let arg: String = "".to_owned();
+ format!("{}", arg);
+ format!("{:?}", arg); // Don't warn about debug.
+ format!("{:8}", arg);
+ format!("{:width$}", arg, width = 8);
+ format!("{:+}", arg); // Warn when the format makes no difference.
+ format!("{:<}", arg); // Warn when the format makes no difference.
+ format!("foo {}", arg);
+ format!("{} bar", arg);
+
+ // We don’t want to warn for non-string args; see issue #697.
+ format!("{}", 42);
+ format!("{:?}", 42);
+ format!("{:+}", 42);
+ format!("foo {}", 42);
+ format!("{} bar", 42);
+
+ // We only want to warn about `format!` itself.
+ println!("foo");
+ println!("{}", "foo");
+ println!("foo {}", "foo");
+ println!("{}", 42);
+ println!("foo {}", 42);
+
+ // A `format!` inside a macro should not trigger a warning.
+ foo!("should not warn");
+
+ // Precision on string means slicing without panicking on size.
+ format!("{:.1}", "foo"); // Could be `"foo"[..1]`
+ format!("{:.10}", "foo"); // Could not be `"foo"[..10]`
+ format!("{:.prec$}", "foo", prec = 1);
+ format!("{:.prec$}", "foo", prec = 10);
+
+ format!("{}", 42.to_string());
+ let x = std::path::PathBuf::from("/bar/foo/qux");
+ format!("{}", x.display().to_string());
+
+ // False positive
+ let a = "foo".to_string();
+ let _ = Some(format!("{}", a + "bar"));
+
+ // Wrap it with braces
+ let v: Vec<String> = vec!["foo".to_string(), "bar".to_string()];
+ let _s: String = format!("{}", &*v.join("\n"));
+
+ format!("prepend {:+}", "s");
+
+ // Issue #8290
+ let x = "foo";
+ let _ = format!("{x}");
+ let _ = format!("{x:?}"); // Don't lint on debug
+ let _ = format!("{y}", y = x);
+
+ // Issue #9234
+ let abc = "abc";
+ let _ = format!("{abc}");
+ let xx = "xx";
+ let _ = format!("{xx}");
+}