1 files changed, 58 insertions, 0 deletions
diff --git a/tests/ui/write_literal.fixed b/tests/ui/write_literal.fixed
new file mode 100644
index 00000000000..ee577574d28
--- /dev/null
+++ b/tests/ui/write_literal.fixed
@@ -0,0 +1,58 @@
+#![warn(clippy::write_literal)]
+#![allow(clippy::uninlined_format_args, unused_must_use)]
+
+use std::io::Write;
+
+fn main() {
+    let mut v = Vec::new();
+
+    // these should be fine
+    write!(v, "Hello");
+    writeln!(v, "Hello");
+    let world = "world";
+    writeln!(v, "Hello {}", world);
+    writeln!(v, "Hello {world}", world = world);
+    writeln!(v, "3 in hex is {:X}", 3);
+    writeln!(v, "2 + 1 = {:.4}", 3);
+    writeln!(v, "2 + 1 = {:5.4}", 3);
+    writeln!(v, "Debug test {:?}", "hello, world");
+    writeln!(v, "{0:8} {1:>8}", "hello", "world");
+    writeln!(v, "{1:8} {0:>8}", "hello", "world");
+    writeln!(v, "{foo:8} {bar:>8}", foo = "hello", bar = "world");
+    writeln!(v, "{bar:8} {foo:>8}", foo = "hello", bar = "world");
+    writeln!(v, "{number:>width$}", number = 1, width = 6);
+    writeln!(v, "{number:>0width$}", number = 1, width = 6);
+    writeln!(v, "{} of {:b} people know binary, the other half doesn't", 1, 2);
+    writeln!(v, "10 / 4 is {}", 2.5);
+    writeln!(v, "2 + 1 = {}", 3);
+    writeln!(v, "From expansion {}", stringify!(not a string literal));
+
+    // these should throw warnings
+    write!(v, "Hello world");
+    //~^ ERROR: literal with an empty format string
+    //~| NOTE: `-D clippy::write-literal` implied by `-D warnings`
+    writeln!(v, "Hello {} world", world);
+    //~^ ERROR: literal with an empty format string
+    writeln!(v, "Hello world");
+    //~^ ERROR: literal with an empty format string
+    writeln!(v, "a literal {:.4}", 5);
+    //~^ ERROR: literal with an empty format string
+
+    // positional args don't change the fact
+    // that we're using a literal -- this should
+    // throw a warning
+    writeln!(v, "hello world");
+    //~^ ERROR: literal with an empty format string
+    //~| ERROR: literal with an empty format string
+    writeln!(v, "world hello");
+    //~^ ERROR: literal with an empty format string
+    //~| ERROR: literal with an empty format string
+
+    // named args shouldn't change anything either
+    writeln!(v, "hello world");
+    //~^ ERROR: literal with an empty format string
+    //~| ERROR: literal with an empty format string
+    writeln!(v, "world hello");
+    //~^ ERROR: literal with an empty format string
+    //~| ERROR: literal with an empty format string
+}