Add run-rustfix to explicit_write test

tests/ui/explicit_write.fixed

@@ -0,0 +1,51 @@
+// run-rustfix
+#![allow(unused_imports)]
+#![warn(clippy::explicit_write)]
+
+fn stdout() -> String {
+    String::new()
+}
+
+fn stderr() -> String {
+    String::new()
+}
+
+fn main() {
+    // these should warn
+    {
+        use std::io::Write;
+        print!("test");
+        eprint!("test");
+        println!("test");
+        eprintln!("test");
+        print!("test");
+        eprint!("test");
+
+        // including newlines
+        println!("test\ntest");
+        eprintln!("test\ntest");
+    }
+    // these should not warn, different destination
+    {
+        use std::fmt::Write;
+        let mut s = String::new();
+        write!(s, "test").unwrap();
+        write!(s, "test").unwrap();
+        writeln!(s, "test").unwrap();
+        writeln!(s, "test").unwrap();
+        s.write_fmt(format_args!("test")).unwrap();
+        s.write_fmt(format_args!("test")).unwrap();
+        write!(stdout(), "test").unwrap();
+        write!(stderr(), "test").unwrap();
+        writeln!(stdout(), "test").unwrap();
+        writeln!(stderr(), "test").unwrap();
+        stdout().write_fmt(format_args!("test")).unwrap();
+        stderr().write_fmt(format_args!("test")).unwrap();
+    }
+    // these should not warn, no unwrap
+    {
+        use std::io::Write;
+        std::io::stdout().write_fmt(format_args!("test")).expect("no stdout");
+        std::io::stderr().write_fmt(format_args!("test")).expect("no stderr");
+    }
+}

tests/ui/explicit_write.rs

@@ -1,3 +1,5 @@
+// run-rustfix
+#![allow(unused_imports)]
 #![warn(clippy::explicit_write)]
 
 fn stdout() -> String {

tests/ui/explicit_write.stderr

@@ -1,5 +1,5 @@
 error: use of `write!(stdout(), ...).unwrap()`
-  --> $DIR/explicit_write.rs:15:9
+  --> $DIR/explicit_write.rs:17:9
    |
 LL |         write!(std::io::stdout(), "test").unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `print!("test")`
@@ -7,43 +7,43 @@ LL |         write!(std::io::stdout(), "test").unwrap();
    = note: `-D clippy::explicit-write` implied by `-D warnings`
 
 error: use of `write!(stderr(), ...).unwrap()`
-  --> $DIR/explicit_write.rs:16:9
+  --> $DIR/explicit_write.rs:18:9
    |
 LL |         write!(std::io::stderr(), "test").unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `eprint!("test")`
 
 error: use of `writeln!(stdout(), ...).unwrap()`
-  --> $DIR/explicit_write.rs:17:9
+  --> $DIR/explicit_write.rs:19:9
    |
 LL |         writeln!(std::io::stdout(), "test").unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `println!("test")`
 
 error: use of `writeln!(stderr(), ...).unwrap()`
-  --> $DIR/explicit_write.rs:18:9
+  --> $DIR/explicit_write.rs:20:9
    |
 LL |         writeln!(std::io::stderr(), "test").unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `eprintln!("test")`
 
 error: use of `stdout().write_fmt(...).unwrap()`
-  --> $DIR/explicit_write.rs:19:9
+  --> $DIR/explicit_write.rs:21:9
    |
 LL |         std::io::stdout().write_fmt(format_args!("test")).unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `print!("test")`
 
 error: use of `stderr().write_fmt(...).unwrap()`
-  --> $DIR/explicit_write.rs:20:9
+  --> $DIR/explicit_write.rs:22:9
    |
 LL |         std::io::stderr().write_fmt(format_args!("test")).unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `eprint!("test")`
 
 error: use of `writeln!(stdout(), ...).unwrap()`
-  --> $DIR/explicit_write.rs:23:9
+  --> $DIR/explicit_write.rs:25:9
    |
 LL |         writeln!(std::io::stdout(), "test/ntest").unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `println!("test/ntest")`
 
 error: use of `writeln!(stderr(), ...).unwrap()`
-  --> $DIR/explicit_write.rs:24:9
+  --> $DIR/explicit_write.rs:26:9
    |
 LL |         writeln!(std::io::stderr(), "test/ntest").unwrap();
    |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ help: try this: `eprintln!("test/ntest")`