Add tests for issue 4573

It's unclear which PR resolved this issue, however the behavior of
adding inline comments to the next line can't be reproduced.

These test cases should serve to prevent a regression.

Author: ytmimi

tests/target/issue_4573.rs

@@ -0,0 +1,245 @@
+// rustmft-version:Two
+// rustmft-use_small_heuristics:Max
+// rustmft-merge_derives:false
+// These are the same rustfmt configuration options that are used
+// in the comiler as of ce39461ca75a and 8eb7c58dbb7b
+// These are commits in https://github.com/rust-lang/rust
+
+#![no_std] // inner attribute comment
+// inner attribute comment
+#![no_implicit_prelude]
+// post inner attribute comment
+
+#[cfg(not(miri))] // inline comment
+#[no_link]
+extern crate foo;
+
+// before attributes
+#[no_link]
+// between attributes
+#[cfg(not(miri))] // inline comment
+extern crate foo as bar;
+
+#[cfg(not(miri))] // inline comment
+// between attribute and use
+use foo;
+
+#[cfg(not(miri))] // inline comment
+use foo;
+
+/* pre attributre */
+#[cfg(not(miri))]
+use foo::bar;
+
+#[cfg(not(miri))] // inline comment
+use foo::bar as FooBar;
+
+#[cfg(not(miri))] // inline comment
+#[allow(unused)]
+#[deprecated(
+    since = "5.2",  // inline inner comment
+    note = "FOO was rarely used. Users should instead use BAR"
+)]
+#[allow(unused)]
+static FOO: i32 = 42;
+
+#[used]
+#[export_name = "FOO"]
+#[cfg(not(miri))] // inline comment
+#[deprecated(
+    since = "5.2",
+    note = "FOO was rarely used. Users should instead use BAR"
+)]
+static FOO: i32 = 42;
+
+#[cfg(not(miri))] // inline comment
+#[export_name = "FOO"]
+static BAR: &'static str = "bar";
+
+#[cfg(not(miri))] // inline comment
+const BAR: i32 = 42;
+
+#[cfg(not(miri))] // inline comment
+#[no_mangle]
+#[link_section = ".example_section"]
+fn foo(bar: usize) {
+    #[cfg(not(miri))] // inline comment
+    println!("hello world!");
+}
+
+#[cfg(not(miri))] // inline comment
+mod foo {}
+
+#[cfg(not(miri))] // inline comment
+extern "C" {
+    fn my_c_function(x: i32) -> bool;
+}
+
+#[cfg(not(miri))] // inline comment
+#[link(name = "CoreFoundation", kind = "framework")]
+extern "C" {
+
+    #[link_name = "actual_symbol_name"] // inline comment
+    // between attribute and function
+    fn my_c_function(x: i32) -> bool;
+}
+
+#[cfg(not(miri))] // inline comment
+pub extern "C" fn callable_from_c(x: i32) -> bool {
+    x % 3 == 0
+}
+
+#[cfg(not(miri))] // inline comment
+/* between attribute block comment */
+#[no_mangle]
+/* between attribute and type */
+type Foo = Bar<u8>;
+
+#[no_mangle]
+#[cfg(not(miri))] // inline comment
+#[non_exhaustive] // inline comment
+enum Foo {
+    Bar,
+    Baz,
+}
+
+#[no_mangle]
+#[cfg(not(miri))] /* inline comment */
+struct Foo<A> {
+    x: A,
+}
+
+#[cfg(not(miri))] // inline comment
+union Foo<A, B> {
+    x: A,
+    y: B,
+}
+
+#[cfg(not(miri))] // inline comment
+trait Foo {}
+
+#[cfg(not(miri))] // inline comment
+trait Foo = Bar + Quux;
+
+#[cfg(not(miri))] // inline comment
+impl Foo {}
+
+#[cfg(not(miri))] // inline comment
+macro_rules! bar {
+    (3) => {};
+}
+
+mod nested {
+    #[cfg(not(miri))] // inline comment
+    // between attribute and use
+    use foo;
+
+    #[cfg(not(miri))] // inline comment
+    use foo;
+
+    #[cfg(not(miri))] // inline comment
+    use foo::bar;
+
+    #[cfg(not(miri))] // inline comment
+    use foo::bar as FooBar;
+
+    #[cfg(not(miri))] // inline comment
+    static FOO: i32 = 42;
+
+    #[cfg(not(miri))] // inline comment
+    static FOO: i32 = 42;
+
+    #[cfg(not(miri))] // inline comment
+    static FOO: &'static str = "bar";
+
+    #[cfg(not(miri))] // inline comment
+    const FOO: i32 = 42;
+
+    #[cfg(not(miri))] // inline comment
+    fn foo(bar: usize) {
+        #[cfg(not(miri))] // inline comment
+        println!("hello world!");
+    }
+
+    #[cfg(not(miri))] // inline comment
+    mod foo {}
+
+    #[cfg(not(miri))] // inline comment
+    mod foo {}
+
+    #[cfg(not(miri))] // inline comment
+    extern "C" {
+        fn my_c_function(x: i32) -> bool;
+    }
+
+    #[cfg(not(miri))] // inline comment
+    #[link(name = "CoreFoundation", kind = "framework")]
+    extern "C" {
+
+        #[link_name = "actual_symbol_name"] // inline comment
+        // between attribute and function
+        fn my_c_function(x: i32) -> bool;
+    }
+
+    #[cfg(not(miri))] // inline comment
+    pub extern "C" fn callable_from_c(x: i32) -> bool {
+        x % 3 == 0
+    }
+
+    #[cfg(not(miri))] // inline comment
+    type Foo = Bar<u8>;
+
+    #[cfg(not(miri))] // inline comment
+    #[non_exhaustive] // inline comment
+    enum Foo {
+        // comment
+        #[attribute_1]
+        #[attribute_2] // comment
+        // comment!
+        Bar,
+        /* comment */
+        #[attribute_1]
+        #[attribute_2] /* comment */
+        #[attribute_3]
+        #[attribute_4]
+        /* comment! */
+        Baz,
+    }
+
+    #[cfg(not(miri))] // inline comment
+    struct Foo<A> {
+        x: A,
+    }
+
+    #[cfg(not(miri))] // inline comment
+    union Foo<A, B> {
+        #[attribute_1]
+        #[attribute_2] /* comment */
+        #[attribute_3]
+        #[attribute_4] // comment
+        x: A,
+        y: B,
+    }
+
+    #[cfg(not(miri))] // inline comment
+    #[allow(missing_docs)]
+    trait Foo {
+        #[must_use] /* comment
+                     * that wrappes to
+                     * the next line */
+        fn bar() {}
+    }
+
+    #[allow(missing_docs)]
+    #[cfg(not(miri))] // inline comment
+    trait Foo = Bar + Quux;
+
+    #[allow(missing_docs)]
+    #[cfg(not(miri))] // inline comment
+    impl Foo {}
+
+    #[cfg(not(miri))] // inline comment
+    macro_rules! bar {
+        (3) => {};
+    }
+}