Merge branch 'master' into 1.4.38-subtree

25 files changed, 848 insertions, 518 deletions

diff --git a/src/attr.rs b/src/attr.rs
index 315eb10a9db..a5982820e3d 100644
--- a/src/attr.rs
+++ b/src/attr.rs
@@ -13,6 +13,7 @@ use crate::lists::{definitive_tactic, itemize_list, write_list, ListFormatting,
 use crate::overflow;
 use crate::rewrite::{Rewrite, RewriteContext};
 use crate::shape::Shape;
+use crate::source_map::SpanUtils;
 use crate::types::{rewrite_path, PathContext};
 use crate::utils::{count_newlines, mk_sp};
 
@@ -116,7 +117,9 @@ fn format_derive(
                 |span| span.lo(),
                 |span| span.hi(),
                 |span| Some(context.snippet(*span).to_owned()),
-                attr.span.lo(),
+                // We update derive attribute spans to start after the opening '('
+                // This helps us focus parsing to just what's inside #[derive(...)]
+                context.snippet_provider.span_after(attr.span, "("),
                 attr.span.hi(),
                 false,
             );
diff --git a/src/bin/main.rs b/src/bin/main.rs
index 4b4aa42d935..1bcc5c0dada 100644
--- a/src/bin/main.rs
+++ b/src/bin/main.rs
@@ -121,7 +121,7 @@ fn make_opts() -> Options {
          found reverts to the input file path",
         "[Path for the configuration file]",
     );
-    opts.optopt("", "edition", "Rust edition to use", "[2015|2018]");
+    opts.optopt("", "edition", "Rust edition to use", "[2015|2018|2021]");
     opts.optopt(
         "",
         "color",
diff --git a/src/cargo-fmt/main.rs b/src/cargo-fmt/main.rs
index 90ffad927e2..1d423ac3491 100644
--- a/src/cargo-fmt/main.rs
+++ b/src/cargo-fmt/main.rs
@@ -17,6 +17,10 @@ use std::str;
 
 use structopt::StructOpt;
 
+#[path = "test/mod.rs"]
+#[cfg(test)]
+mod cargo_fmt_tests;
+
 #[derive(StructOpt, Debug)]
 #[structopt(
     bin_name = "cargo fmt",
@@ -36,7 +40,7 @@ pub struct Opts {
     #[structopt(long = "version")]
     version: bool,
 
-    /// Specify package to format (only usable in workspaces)
+    /// Specify package to format
     #[structopt(short = "p", long = "package", value_name = "package")]
     packages: Vec<String>,
 
@@ -53,9 +57,13 @@ pub struct Opts {
     #[structopt(name = "rustfmt_options", raw(true))]
     rustfmt_options: Vec<String>,
 
-    /// Format all packages (only usable in workspaces)
+    /// Format all packages, and also their local path-based dependencies
     #[structopt(long = "all")]
     format_all: bool,
+
+    /// Run rustfmt in check mode
+    #[structopt(long = "check")]
+    check: bool,
 }
 
 fn main() {
@@ -104,6 +112,12 @@ fn execute() -> i32 {
 
     let strategy = CargoFmtStrategy::from_opts(&opts);
     let mut rustfmt_args = opts.rustfmt_options;
+    if opts.check {
+        let check_flag = "--check";
+        if !rustfmt_args.iter().any(|o| o == check_flag) {
+            rustfmt_args.push(check_flag.to_owned());
+        }
+    }
     if let Some(message_format) = opts.message_format {
         if let Err(msg) = convert_message_format_to_rustfmt_args(&message_format, &mut rustfmt_args)
         {
@@ -346,7 +360,7 @@ fn get_targets_root_only(
     manifest_path: Option<&Path>,
     targets: &mut BTreeSet<Target>,
 ) -> Result<(), io::Error> {
-    let metadata = get_cargo_metadata(manifest_path, false)?;
+    let metadata = get_cargo_metadata(manifest_path)?;
     let workspace_root_path = PathBuf::from(&metadata.workspace_root).canonicalize()?;
     let (in_workspace_root, current_dir_manifest) = if let Some(target_manifest) = manifest_path {
         (
@@ -390,34 +404,29 @@ fn get_targets_recursive(
     mut targets: &mut BTreeSet<Target>,
     visited: &mut BTreeSet<String>,
 ) -> Result<(), io::Error> {
-    let metadata = get_cargo_metadata(manifest_path, false)?;
-    let metadata_with_deps = get_cargo_metadata(manifest_path, true)?;
-
-    for package in metadata.packages {
+    let metadata = get_cargo_metadata(manifest_path)?;
+    for package in &metadata.packages {
         add_targets(&package.targets, &mut targets);
 
-        // Look for local dependencies.
-        for dependency in package.dependencies {
-            if dependency.source.is_some() || visited.contains(&dependency.name) {
+        // Look for local dependencies using information available since cargo v1.51
+        // It's theoretically possible someone could use a newer version of rustfmt with
+        // a much older version of `cargo`, but we don't try to explicitly support that scenario.
+        // If someone reports an issue with path-based deps not being formatted, be sure to
+        // confirm their version of `cargo` (not `cargo-fmt`) is >= v1.51
+        // https://github.com/rust-lang/cargo/pull/8994
+        for dependency in &package.dependencies {
+            if dependency.path.is_none() || visited.contains(&dependency.name) {
                 continue;
             }
 
-            let dependency_package = metadata_with_deps
-                .packages
-                .iter()
-                .find(|p| p.name == dependency.name && p.source.is_none());
-            let manifest_path = if let Some(dep_pkg) = dependency_package {
-                PathBuf::from(&dep_pkg.manifest_path)
-            } else {
-                let mut package_manifest_path = PathBuf::from(&package.manifest_path);
-                package_manifest_path.pop();
-                package_manifest_path.push(&dependency.name);
-                package_manifest_path.push("Cargo.toml");
-                package_manifest_path
-            };
-
-            if manifest_path.exists() {
-                visited.insert(dependency.name);
+            let manifest_path = PathBuf::from(dependency.path.as_ref().unwrap()).join("Cargo.toml");
+            if manifest_path.exists()
+                && !metadata
+                    .packages
+                    .iter()
+                    .any(|p| p.manifest_path.eq(&manifest_path))
+            {
+                visited.insert(dependency.name.to_owned());
                 get_targets_recursive(Some(&manifest_path), &mut targets, visited)?;
             }
         }
@@ -431,8 +440,7 @@ fn get_targets_with_hitlist(
     hitlist: &[String],
     targets: &mut BTreeSet<Target>,
 ) -> Result<(), io::Error> {
-    let metadata = get_cargo_metadata(manifest_path, false)?;
-
+    let metadata = get_cargo_metadata(manifest_path)?;
     let mut workspace_hitlist: BTreeSet<&String> = BTreeSet::from_iter(hitlist);
 
     for package in metadata.packages {
@@ -517,18 +525,13 @@ fn run_rustfmt(
         .unwrap_or(SUCCESS))
 }
 
-fn get_cargo_metadata(
-    manifest_path: Option<&Path>,
-    include_deps: bool,
-) -> Result<cargo_metadata::Metadata, io::Error> {
+fn get_cargo_metadata(manifest_path: Option<&Path>) -> Result<cargo_metadata::Metadata, io::Error> {
     let mut cmd = cargo_metadata::MetadataCommand::new();
-    if !include_deps {
-        cmd.no_deps();
-    }
+    cmd.no_deps();
     if let Some(manifest_path) = manifest_path {
         cmd.manifest_path(manifest_path);
     }
-    cmd.other_options(&[String::from("--offline")]);
+    cmd.other_options(vec![String::from("--offline")]);
 
     match cmd.exec() {
         Ok(metadata) => Ok(metadata),
@@ -541,221 +544,3 @@ fn get_cargo_metadata(
         }
     }
 }
-
-#[cfg(test)]
-mod cargo_fmt_tests {
-    use super::*;
-
-    #[test]
-    fn default_options() {
-        let empty: Vec<String> = vec![];
-        let o = Opts::from_iter(&empty);
-        assert_eq!(false, o.quiet);
-        assert_eq!(false, o.verbose);
-        assert_eq!(false, o.version);
-        assert_eq!(empty, o.packages);
-        assert_eq!(empty, o.rustfmt_options);
-        assert_eq!(false, o.format_all);
-        assert_eq!(None, o.manifest_path);
-        assert_eq!(None, o.message_format);
-    }
-
-    #[test]
-    fn good_options() {
-        let o = Opts::from_iter(&[
-            "test",
-            "-q",
-            "-p",
-            "p1",
-            "-p",
-            "p2",
-            "--message-format",
-            "short",
-            "--",
-            "--edition",
-            "2018",
-        ]);
-        assert_eq!(true, o.quiet);
-        assert_eq!(false, o.verbose);
-        assert_eq!(false, o.version);
-        assert_eq!(vec!["p1", "p2"], o.packages);
-        assert_eq!(vec!["--edition", "2018"], o.rustfmt_options);
-        assert_eq!(false, o.format_all);
-        assert_eq!(Some(String::from("short")), o.message_format);
-    }
-
-    #[test]
-    fn unexpected_option() {
-        assert!(
-            Opts::clap()
-                .get_matches_from_safe(&["test", "unexpected"])
-                .is_err()
-        );
-    }
-
-    #[test]
-    fn unexpected_flag() {
-        assert!(
-            Opts::clap()
-                .get_matches_from_safe(&["test", "--flag"])
-                .is_err()
-        );
-    }
-
-    #[test]
-    fn mandatory_separator() {
-        assert!(
-            Opts::clap()
-                .get_matches_from_safe(&["test", "--check"])
-                .is_err()
-        );
-        assert!(
-            !Opts::clap()
-                .get_matches_from_safe(&["test", "--", "--check"])
-                .is_err()
-        );
-    }
-
-    #[test]
-    fn multiple_packages_one_by_one() {
-        let o = Opts::from_iter(&[
-            "test",
-            "-p",
-            "package1",
-            "--package",
-            "package2",
-            "-p",
-            "package3",
-        ]);
-        assert_eq!(3, o.packages.len());
-    }
-
-    #[test]
-    fn multiple_packages_grouped() {
-        let o = Opts::from_iter(&[
-            "test",
-            "--package",
-            "package1",
-            "package2",
-            "-p",
-            "package3",
-            "package4",
-        ]);
-        assert_eq!(4, o.packages.len());
-    }
-
-    #[test]
-    fn empty_packages_1() {
-        assert!(Opts::clap().get_matches_from_safe(&["test", "-p"]).is_err());
-    }
-
-    #[test]
-    fn empty_packages_2() {
-        assert!(
-            Opts::clap()
-                .get_matches_from_safe(&["test", "-p", "--", "--check"])
-                .is_err()
-        );
-    }
-
-    #[test]
-    fn empty_packages_3() {
-        assert!(
-            Opts::clap()
-                .get_matches_from_safe(&["test", "-p", "--verbose"])
-                .is_err()
-        );
-    }
-
-    #[test]
-    fn empty_packages_4() {
-        assert!(
-            Opts::clap()
-                .get_matches_from_safe(&["test", "-p", "--check"])
-                .is_err()
-        );
-    }
-
-    mod convert_message_format_to_rustfmt_args_tests {
-        use super::*;
-
-        #[test]
-        fn invalid_message_format() {
-            assert_eq!(
-                convert_message_format_to_rustfmt_args("awesome", &mut vec![]),
-                Err(String::from(
-                    "invalid --message-format value: awesome. Allowed values are: short|json|human"
-                )),
-            );
-        }
-
-        #[test]
-        fn json_message_format_and_check_arg() {
-            let mut args = vec![String::from("--check")];
-            assert_eq!(
-                convert_message_format_to_rustfmt_args("json", &mut args),
-                Err(String::from(
-                    "cannot include --check arg when --message-format is set to json"
-                )),
-            );
-        }
-
-        #[test]
-        fn json_message_format_and_emit_arg() {
-            let mut args = vec![String::from("--emit"), String::from("checkstyle")];
-            assert_eq!(
-                convert_message_format_to_rustfmt_args("json", &mut args),
-                Err(String::from(
-                    "cannot include --emit arg when --message-format is set to json"
-                )),
-            );
-        }
-
-        #[test]
-        fn json_message_format() {
-            let mut args = vec![String::from("--edition"), String::from("2018")];
-            assert!(convert_message_format_to_rustfmt_args("json", &mut args).is_ok());
-            assert_eq!(
-                args,
-                vec![
-                    String::from("--edition"),
-                    String::from("2018"),
-                    String::from("--emit"),
-                    String::from("json")
-                ]
-            );
-        }
-
-        #[test]
-        fn human_message_format() {
-            let exp_args = vec![String::from("--emit"), String::from("json")];
-            let mut act_args = exp_args.clone();
-            assert!(convert_message_format_to_rustfmt_args("human", &mut act_args).is_ok());
-            assert_eq!(act_args, exp_args);
-        }
-
-        #[test]
-        fn short_message_format() {
-            let mut args = vec![String::from("--check")];
-            assert!(convert_message_format_to_rustfmt_args("short", &mut args).is_ok());
-            assert_eq!(args, vec![String::from("--check"), String::from("-l")]);
-        }
-
-        #[test]
-        fn short_message_format_included_short_list_files_flag() {
-            let mut args = vec![String::from("--check"), String::from("-l")];
-            assert!(convert_message_format_to_rustfmt_args("short", &mut args).is_ok());
-            assert_eq!(args, vec![String::from("--check"), String::from("-l")]);
-        }
-
-        #[test]
-        fn short_message_format_included_long_list_files_flag() {
-            let mut args = vec![String::from("--check"), String::from("--files-with-diff")];
-            assert!(convert_message_format_to_rustfmt_args("short", &mut args).is_ok());
-            assert_eq!(
-                args,
-                vec![String::from("--check"), String::from("--files-with-diff")]
-            );
-        }
-    }
-}
diff --git a/src/cargo-fmt/test/message_format.rs b/src/cargo-fmt/test/message_format.rs
new file mode 100644
index 00000000000..bf44924f13c
--- /dev/null
+++ b/src/cargo-fmt/test/message_format.rs
@@ -0,0 +1,80 @@
+use super::*;
+
+#[test]
+fn invalid_message_format() {
+    assert_eq!(
+        convert_message_format_to_rustfmt_args("awesome", &mut vec![]),
+        Err(String::from(
+            "invalid --message-format value: awesome. Allowed values are: short|json|human"
+        )),
+    );
+}
+
+#[test]
+fn json_message_format_and_check_arg() {
+    let mut args = vec![String::from("--check")];
+    assert_eq!(
+        convert_message_format_to_rustfmt_args("json", &mut args),
+        Err(String::from(
+            "cannot include --check arg when --message-format is set to json"
+        )),
+    );
+}
+
+#[test]
+fn json_message_format_and_emit_arg() {
+    let mut args = vec![String::from("--emit"), String::from("checkstyle")];
+    assert_eq!(
+        convert_message_format_to_rustfmt_args("json", &mut args),
+        Err(String::from(
+            "cannot include --emit arg when --message-format is set to json"
+        )),
+    );
+}
+
+#[test]
+fn json_message_format() {
+    let mut args = vec![String::from("--edition"), String::from("2018")];
+    assert!(convert_message_format_to_rustfmt_args("json", &mut args).is_ok());
+    assert_eq!(
+        args,
+        vec![
+            String::from("--edition"),
+            String::from("2018"),
+            String::from("--emit"),
+            String::from("json")
+        ]
+    );
+}
+
+#[test]
+fn human_message_format() {
+    let exp_args = vec![String::from("--emit"), String::from("json")];
+    let mut act_args = exp_args.clone();
+    assert!(convert_message_format_to_rustfmt_args("human", &mut act_args).is_ok());
+    assert_eq!(act_args, exp_args);
+}
+
+#[test]
+fn short_message_format() {
+    let mut args = vec![String::from("--check")];
+    assert!(convert_message_format_to_rustfmt_args("short", &mut args).is_ok());
+    assert_eq!(args, vec![String::from("--check"), String::from("-l")]);
+}
+
+#[test]
+fn short_message_format_included_short_list_files_flag() {
+    let mut args = vec![String::from("--check"), String::from("-l")];
+    assert!(convert_message_format_to_rustfmt_args("short", &mut args).is_ok());
+    assert_eq!(args, vec![String::from("--check"), String::from("-l")]);
+}
+
+#[test]
+fn short_message_format_included_long_list_files_flag() {
+    let mut args = vec![String::from("--check"), String::from("--files-with-diff")];
+    assert!(convert_message_format_to_rustfmt_args("short", &mut args).is_ok());
+    assert_eq!(
+        args,
+        vec![String::from("--check"), String::from("--files-with-diff")]
+    );
+}
diff --git a/src/cargo-fmt/test/mod.rs b/src/cargo-fmt/test/mod.rs
new file mode 100644
index 00000000000..360503632c7
--- /dev/null
+++ b/src/cargo-fmt/test/mod.rs
@@ -0,0 +1,137 @@
+use super::*;
+
+mod message_format;
+mod targets;
+
+#[test]
+fn default_options() {
+    let empty: Vec<String> = vec![];
+    let o = Opts::from_iter(&empty);
+    assert_eq!(false, o.quiet);
+    assert_eq!(false, o.verbose);
+    assert_eq!(false, o.version);
+    assert_eq!(false, o.check);
+    assert_eq!(empty, o.packages);
+    assert_eq!(empty, o.rustfmt_options);
+    assert_eq!(false, o.format_all);
+    assert_eq!(None, o.manifest_path);
+    assert_eq!(None, o.message_format);
+}
+
+#[test]
+fn good_options() {
+    let o = Opts::from_iter(&[
+        "test",
+        "-q",
+        "-p",
+        "p1",
+        "-p",
+        "p2",
+        "--message-format",
+        "short",
+        "--check",
+        "--",
+        "--edition",
+        "2018",
+    ]);
+    assert_eq!(true, o.quiet);
+    assert_eq!(false, o.verbose);
+    assert_eq!(false, o.version);
+    assert_eq!(true, o.check);
+    assert_eq!(vec!["p1", "p2"], o.packages);
+    assert_eq!(vec!["--edition", "2018"], o.rustfmt_options);
+    assert_eq!(false, o.format_all);
+    assert_eq!(Some(String::from("short")), o.message_format);
+}
+
+#[test]
+fn unexpected_option() {
+    assert!(
+        Opts::clap()
+            .get_matches_from_safe(&["test", "unexpected"])
+            .is_err()
+    );
+}
+
+#[test]
+fn unexpected_flag() {
+    assert!(
+        Opts::clap()
+            .get_matches_from_safe(&["test", "--flag"])
+            .is_err()
+    );
+}
+
+#[test]
+fn mandatory_separator() {
+    assert!(
+        Opts::clap()
+            .get_matches_from_safe(&["test", "--emit"])
+            .is_err()
+    );
+    assert!(
+        !Opts::clap()
+            .get_matches_from_safe(&["test", "--", "--emit"])
+            .is_err()
+    );
+}
+
+#[test]
+fn multiple_packages_one_by_one() {
+    let o = Opts::from_iter(&[
+        "test",
+        "-p",
+        "package1",
+        "--package",
+        "package2",
+        "-p",
+        "package3",
+    ]);
+    assert_eq!(3, o.packages.len());
+}
+
+#[test]
+fn multiple_packages_grouped() {
+    let o = Opts::from_iter(&[
+        "test",
+        "--package",
+        "package1",
+        "package2",
+        "-p",
+        "package3",
+        "package4",
+    ]);
+    assert_eq!(4, o.packages.len());
+}
+
+#[test]
+fn empty_packages_1() {
+    assert!(Opts::clap().get_matches_from_safe(&["test", "-p"]).is_err());
+}
+
+#[test]
+fn empty_packages_2() {
+    assert!(
+        Opts::clap()
+            .get_matches_from_safe(&["test", "-p", "--", "--check"])
+            .is_err()
+    );
+}
+
+#[test]
+fn empty_packages_3() {
+    assert!(
+        Opts::clap()
+            .get_matches_from_safe(&["test", "-p", "--verbose"])
+            .is_err()
+    );
+}
+
+#[test]
+fn empty_packages_4() {
+    assert!(
+        Opts::clap()
+            .get_matches_from_safe(&["test", "-p", "--check"])
+            .is_err()
+    );
+}
diff --git a/src/cargo-fmt/test/targets.rs b/src/cargo-fmt/test/targets.rs
new file mode 100644
index 00000000000..b7e7fabdf71
--- /dev/null
+++ b/src/cargo-fmt/test/targets.rs
@@ -0,0 +1,134 @@
+use super::*;
+
+struct ExpTarget {
+    path: &'static str,
+    edition: &'static str,
+    kind: &'static str,
+}
+
+mod all_targets {
+    use super::*;
+
+    fn assert_correct_targets_loaded(
+        manifest_suffix: &str,
+        source_root: &str,
+        exp_targets: &[ExpTarget],
+        exp_num_targets: usize,
+    ) {
+        let root_path = Path::new("tests/cargo-fmt/source").join(source_root);
+        let get_path = |exp: &str| PathBuf::from(&root_path).join(exp).canonicalize().unwrap();
+        let manifest_path = Path::new(&root_path).join(manifest_suffix);
+        let targets = get_targets(&CargoFmtStrategy::All, Some(manifest_path.as_path()))
+            .expect("Targets should have been loaded");
+
+        assert_eq!(targets.len(), exp_num_targets);
+
+        for target in exp_targets {
+            assert!(targets.contains(&Target {
+                path: get_path(target.path),
+                edition: target.edition.to_owned(),
+                kind: target.kind.to_owned(),
+            }));
+        }
+    }
+
+    mod different_crate_and_dir_names {
+        use super::*;
+
+        fn assert_correct_targets_loaded(manifest_suffix: &str) {
+            let exp_targets = vec![
+                ExpTarget {
+                    path: "dependency-dir-name/subdep-dir-name/src/lib.rs",
+                    edition: "2018",
+                    kind: "lib",
+                },
+                ExpTarget {
+                    path: "dependency-dir-name/src/lib.rs",
+                    edition: "2018",
+                    kind: "lib",
+                },
+                ExpTarget {
+                    path: "src/main.rs",
+                    edition: "2018",
+                    kind: "main",
+                },
+            ];
+            super::assert_correct_targets_loaded(
+                manifest_suffix,
+                "divergent-crate-dir-names",
+                &exp_targets,
+                3,
+            );
+        }
+
+        #[test]
+        fn correct_targets_from_root() {
+            assert_correct_targets_loaded("Cargo.toml");
+        }
+
+        #[test]
+        fn correct_targets_from_sub_local_dep() {
+            assert_correct_targets_loaded("dependency-dir-name/Cargo.toml");
+        }
+    }
+
+    mod workspaces {
+        use super::*;
+
+        fn assert_correct_targets_loaded(manifest_suffix: &str) {
+            let exp_targets = vec![
+                ExpTarget {
+                    path: "ws/a/src/main.rs",
+                    edition: "2018",
+                    kind: "bin",
+                },
+                ExpTarget {
+                    path: "ws/b/src/main.rs",
+                    edition: "2018",
+                    kind: "bin",
+                },
+                ExpTarget {
+                    path: "ws/c/src/lib.rs",
+                    edition: "2018",
+                    kind: "lib",
+                },
+                ExpTarget {
+                    path: "ws/a/d/src/lib.rs",
+                    edition: "2018",
+                    kind: "lib",
+                },
+                ExpTarget {
+                    path: "e/src/main.rs",
+                    edition: "2018",
+                    kind: "main",
+                },
+                ExpTarget {
+                    path: "ws/a/d/f/src/lib.rs",
+                    edition: "2018",
+                    kind: "lib",
+                },
+            ];
+            super::assert_correct_targets_loaded(
+                manifest_suffix,
+                "workspaces/path-dep-above",
+                &exp_targets,
+                6,
+            );
+        }
+
+        #[test]
+        fn includes_outside_workspace_deps() {
+            assert_correct_targets_loaded("ws/Cargo.toml");
+        }
+
+        #[test]
+        fn includes_workspace_from_dep_above() {
+            assert_correct_targets_loaded("e/Cargo.toml");
+        }
+
+        #[test]
+        fn includes_all_packages_from_workspace_subdir() {
+            assert_correct_targets_loaded("ws/a/d/f/Cargo.toml");
+        }
+    }
+}
diff --git a/src/comment.rs b/src/comment.rs
index 58a2b5e6aec..60825424858 100644
--- a/src/comment.rs
+++ b/src/comment.rs
@@ -10,7 +10,8 @@ use crate::rewrite::RewriteContext;
 use crate::shape::{Indent, Shape};
 use crate::string::{rewrite_string, StringFormat};
 use crate::utils::{
-    count_newlines, first_line_width, last_line_width, trim_left_preserve_layout, unicode_str_width,
+    count_newlines, first_line_width, last_line_width, trim_left_preserve_layout,
+    trimmed_last_line_width, unicode_str_width,
 };
 use crate::{ErrorKind, FormattingError};
 
@@ -171,11 +172,12 @@ pub(crate) fn combine_strs_with_missing_comments(
         String::with_capacity(prev_str.len() + next_str.len() + shape.indent.width() + 128);
     result.push_str(prev_str);
     let mut allow_one_line = !prev_str.contains('\n') && !next_str.contains('\n');
-    let first_sep = if prev_str.is_empty() || next_str.is_empty() {
-        ""
-    } else {
-        " "
-    };
+    let first_sep =
+        if prev_str.is_empty() || next_str.is_empty() || trimmed_last_line_width(prev_str) == 0 {
+            ""
+        } else {
+            " "
+        };
     let mut one_line_width =
         last_line_width(prev_str) + first_line_width(next_str) + first_sep.len();
 
@@ -184,7 +186,7 @@ pub(crate) fn combine_strs_with_missing_comments(
     let missing_comment = rewrite_missing_comment(span, shape, context)?;
 
     if missing_comment.is_empty() {
-        if allow_extend && prev_str.len() + first_sep.len() + next_str.len() <= shape.width {
+        if allow_extend && one_line_width <= shape.width {
             result.push_str(first_sep);
         } else if !prev_str.is_empty() {
             result.push_str(&indent.to_string_with_newline(config))
@@ -392,28 +394,26 @@ fn identify_comment(
     }
 }
 
-/// Attributes for code blocks in rustdoc.
-/// See <https://doc.rust-lang.org/rustdoc/print.html#attributes>.
+/// Enum indicating if the code block contains rust based on attributes
 enum CodeBlockAttribute {
     Rust,
-    Ignore,
-    Text,
-    ShouldPanic,
-    NoRun,
-    CompileFail,
+    NotRust,
 }
 
 impl CodeBlockAttribute {
-    fn new(attribute: &str) -> CodeBlockAttribute {
-        match attribute {
-            "rust" | "" => CodeBlockAttribute::Rust,
-            "ignore" => CodeBlockAttribute::Ignore,
-            "text" => CodeBlockAttribute::Text,
-            "should_panic" => CodeBlockAttribute::ShouldPanic,
-            "no_run" => CodeBlockAttribute::NoRun,
-            "compile_fail" => CodeBlockAttribute::CompileFail,
-            _ => CodeBlockAttribute::Text,
+    /// Parse comma separated attributes list. Return rust only if all
+    /// attributes are valid rust attributes
+    /// See https://doc.rust-lang.org/rustdoc/print.html#attributes
+    fn new(attributes: &str) -> CodeBlockAttribute {
+        for attribute in attributes.split(",") {
+            match attribute.trim() {
+                "" | "rust" | "should_panic" | "no_run" | "edition2015" | "edition2018"
+                | "edition2021" => (),
+                "ignore" | "compile_fail" | "text" => return CodeBlockAttribute::NotRust,
+                _ => return CodeBlockAttribute::NotRust,
+            }
         }
+        CodeBlockAttribute::Rust
     }
 }
 
@@ -647,25 +647,21 @@ impl<'a> CommentRewrite<'a> {
         } else if self.code_block_attr.is_some() {
             if line.starts_with("```") {
                 let code_block = match self.code_block_attr.as_ref().unwrap() {
-                    CodeBlockAttribute::Ignore | CodeBlockAttribute::Text => {
-                        trim_custom_comment_prefix(&self.code_block_buffer)
-                    }
-                    _ if self.code_block_buffer.is_empty() => String::new(),
-                    _ => {
+                    CodeBlockAttribute::Rust
+                        if self.fmt.config.format_code_in_doc_comments()
+                            && !self.code_block_buffer.is_empty() =>
+                    {
                         let mut config = self.fmt.config.clone();
                         config.set().wrap_comments(false);
-                        if config.format_code_in_doc_comments() {
-                            if let Some(s) =
-                                crate::format_code_block(&self.code_block_buffer, &config, false)
-                            {
-                                trim_custom_comment_prefix(&s.snippet)
-                            } else {
-                                trim_custom_comment_prefix(&self.code_block_buffer)
-                            }
+                        if let Some(s) =
+                            crate::format_code_block(&self.code_block_buffer, &config, false)
+                        {
+                            trim_custom_comment_prefix(&s.snippet)
                         } else {
                             trim_custom_comment_prefix(&self.code_block_buffer)
                         }
                     }
+                    _ => trim_custom_comment_prefix(&self.code_block_buffer),
                 };
                 if !code_block.is_empty() {
                     self.result.push_str(&self.comment_line_separator);
diff --git a/src/config/mod.rs b/src/config/mod.rs
index 8c04363b1fd..c5419d860c9 100644
--- a/src/config/mod.rs
+++ b/src/config/mod.rs
@@ -69,6 +69,8 @@ create_config! {
     format_macro_matchers: bool, false, false,
         "Format the metavariable matching patterns in macros";
     format_macro_bodies: bool, true, false, "Format the bodies of macros";
+    hex_literal_case: HexLiteralCase, HexLiteralCase::Preserve, false,
+        "Format hexadecimal integer literals";
 
     // Single line expressions and items
     empty_item_single_line: bool, true, false,
@@ -125,7 +127,7 @@ create_config! {
         "Add trailing semicolon after break, continue and return";
     trailing_comma: SeparatorTactic, SeparatorTactic::Vertical, false,
         "How to handle trailing commas for lists";
-    match_block_trailing_comma: bool, false, false,
+    match_block_trailing_comma: bool, false, true,
         "Put a trailing comma after a block based match arm (non-block arms are not affected)";
     blank_lines_upper_bound: usize, 1, false,
         "Maximum number of blank lines which can be put between items";
@@ -136,6 +138,7 @@ create_config! {
     inline_attribute_width: usize, 0, false,
         "Write an item and its attribute on the same line \
         if their combined width is below a threshold";
+    format_generated_files: bool, false, false, "Format generated files";
 
     // Options that can change the source code beyond whitespace/blocks (somewhat linty things)
     merge_derives: bool, true, true, "Merge multiple `#[derive(...)]` into a single one";
@@ -152,7 +155,7 @@ create_config! {
         "Require a specific version of rustfmt";
     unstable_features: bool, false, false,
             "Enables unstable features. Only available on nightly channel";
-    disable_all_formatting: bool, false, false, "Don't reformat anything";
+    disable_all_formatting: bool, false, true, "Don't reformat anything";
     skip_children: bool, false, false, "Don't reformat out of line modules";
     hide_parse_errors: bool, false, false, "Hide errors from the parser";
     error_on_line_overflow: bool, false, false, "Error if unable to get all lines within max_width";
@@ -569,6 +572,7 @@ license_template_path = ""
 format_strings = false
 format_macro_matchers = false
 format_macro_bodies = true
+hex_literal_case = "Preserve"
 empty_item_single_line = true
 struct_lit_single_line = true
 fn_single_line = false
@@ -604,6 +608,7 @@ blank_lines_lower_bound = 0
 edition = "2015"
 version = "One"
 inline_attribute_width = 0
+format_generated_files = false
 merge_derives = true
 use_try_shorthand = false
 use_field_init_shorthand = false
diff --git a/src/config/options.rs b/src/config/options.rs
index 3b91021813c..e92f8e8a531 100644
--- a/src/config/options.rs
+++ b/src/config/options.rs
@@ -125,6 +125,19 @@ pub enum ImportGranularity {
     Module,
     /// Use one `use` statement per imported item.
     Item,
+    /// Use one `use` statement including all items.
+    One,
+}
+
+/// Controls how rustfmt should handle case in hexadecimal literals.
+#[config_type]
+pub enum HexLiteralCase {
+    /// Leave the literal as-is
+    Preserve,
+    /// Ensure all literals use uppercase lettering
+    Upper,
+    /// Ensure all literals use lowercase lettering
+    Lower,
 }
 
 #[config_type]
diff --git a/src/expr.rs b/src/expr.rs
index 975af6c0294..7f1dd363f93 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -13,7 +13,7 @@ use crate::comment::{
     rewrite_missing_comment, CharClasses, FindUncommented,
 };
 use crate::config::lists::*;
-use crate::config::{Config, ControlBraceStyle, IndentStyle, Version};
+use crate::config::{Config, ControlBraceStyle, HexLiteralCase, IndentStyle, Version};
 use crate::lists::{
     definitive_tactic, itemize_list, shape_for_tactic, struct_lit_formatting, struct_lit_shape,
     struct_lit_tactic, write_list, ListFormatting, Separator,
@@ -822,7 +822,7 @@ impl<'a> ControlFlow<'a> {
             let pat_string = pat.rewrite(context, pat_shape)?;
             let comments_lo = context
                 .snippet_provider
-                .span_after(self.span, self.connector.trim());
+                .span_after(self.span.with_lo(pat.span.hi()), self.connector.trim());
             let comments_span = mk_sp(comments_lo, expr.span.lo());
             return rewrite_assign_rhs_with_comments(
                 context,
@@ -1168,6 +1168,7 @@ pub(crate) fn rewrite_literal(
 ) -> Option<String> {
     match l.kind {
         ast::LitKind::Str(_, ast::StrStyle::Cooked) => rewrite_string_lit(context, l.span, shape),
+        ast::LitKind::Int(..) => rewrite_int_lit(context, l, shape),
         _ => wrap_str(
             context.snippet(l.span).to_owned(),
             context.config.max_width(),
@@ -1202,6 +1203,36 @@ fn rewrite_string_lit(context: &RewriteContext<'_>, span: Span, shape: Shape) ->
     )
 }
 
+fn rewrite_int_lit(context: &RewriteContext<'_>, lit: &ast::Lit, shape: Shape) -> Option<String> {
+    let span = lit.span;
+    let symbol = lit.token.symbol.as_str();
+
+    if symbol.starts_with("0x") {
+        let hex_lit = match context.config.hex_literal_case() {
+            HexLiteralCase::Preserve => None,
+            HexLiteralCase::Upper => Some(symbol[2..].to_ascii_uppercase()),
+            HexLiteralCase::Lower => Some(symbol[2..].to_ascii_lowercase()),
+        };
+        if let Some(hex_lit) = hex_lit {
+            return wrap_str(
+                format!(
+                    "0x{}{}",
+                    hex_lit,
+                    lit.token.suffix.map_or(String::new(), |s| s.to_string())
+                ),
+                context.config.max_width(),
+                shape,
+            );
+        }
+    }
+
+    wrap_str(
+        context.snippet(span).to_owned(),
+        context.config.max_width(),
+        shape,
+    )
+}
+
 fn choose_separator_tactic(context: &RewriteContext<'_>, span: Span) -> Option<SeparatorTactic> {
     if context.inside_macro() {
         if span_ends_with_comma(context, span) {
@@ -1497,12 +1528,12 @@ fn rewrite_struct_lit<'a>(
     let path_shape = shape.sub_width(2)?;
     let path_str = rewrite_path(context, PathContext::Expr, None, path, path_shape)?;
 
-    let has_base = match struct_rest {
+    let has_base_or_rest = match struct_rest {
         ast::StructRest::None if fields.is_empty() => return Some(format!("{} {{}}", path_str)),
         ast::StructRest::Rest(_) if fields.is_empty() => {
             return Some(format!("{} {{ .. }}", path_str));
         }
-        ast::StructRest::Base(_) => true,
+        ast::StructRest::Rest(_) | ast::StructRest::Base(_) => true,
         _ => false,
     };
 
@@ -1511,7 +1542,7 @@ fn rewrite_struct_lit<'a>(
 
     let one_line_width = h_shape.map_or(0, |shape| shape.width);
     let body_lo = context.snippet_provider.span_after(span, "{");
-    let fields_str = if struct_lit_can_be_aligned(fields, has_base)
+    let fields_str = if struct_lit_can_be_aligned(fields, has_base_or_rest)
         && context.config.struct_field_align_threshold() > 0
     {
         rewrite_with_alignment(
@@ -1583,10 +1614,7 @@ fn rewrite_struct_lit<'a>(
             nested_shape,
             tactic,
             context,
-            force_no_trailing_comma
-                || has_base
-                || !context.use_block_indent()
-                || matches!(struct_rest, ast::StructRest::Rest(_)),
+            force_no_trailing_comma || has_base_or_rest || !context.use_block_indent(),
         );
 
         write_list(&item_vec, &fmt)?
diff --git a/src/formatting.rs b/src/formatting.rs
index e0403574eeb..9ef47b887ca 100644
--- a/src/formatting.rs
+++ b/src/formatting.rs
@@ -10,6 +10,7 @@ use rustc_span::Span;
 use self::newline_style::apply_newline_style;
 use crate::comment::{CharClasses, FullCodeCharKind};
 use crate::config::{Config, FileName, Verbosity};
+use crate::formatting::generated::is_generated_file;
 use crate::issues::BadIssueSeeker;
 use crate::modules::Module;
 use crate::syntux::parser::{DirectoryOwnership, Parser, ParserError};
@@ -18,6 +19,7 @@ use crate::utils::count_newlines;
 use crate::visitor::FmtVisitor;
 use crate::{modules, source_file, ErrorKind, FormatReport, Input, Session};
 
+mod generated;
 mod newline_style;
 
 // A map of the files of a crate, with their new content
@@ -103,7 +105,12 @@ fn format_project<T: FormatHandler>(
     context.parse_session.set_silent_emitter();
 
     for (path, module) in files {
-        let should_ignore = !input_is_stdin && context.ignore_file(&path);
+        let source_file = context.parse_session.span_to_file_contents(module.span);
+        let src = source_file.src.as_ref().expect("SourceFile without src");
+
+        let should_ignore = (!input_is_stdin && context.ignore_file(&path))
+            || (!config.format_generated_files() && is_generated_file(src));
+
         if (config.skip_children() && path != main_file) || should_ignore {
             continue;
         }
diff --git a/src/formatting/generated.rs b/src/formatting/generated.rs
new file mode 100644
index 00000000000..58f43f17ee1
--- /dev/null
+++ b/src/formatting/generated.rs
@@ -0,0 +1,7 @@
+/// Returns `true` if the given span is a part of generated files.
+pub(super) fn is_generated_file(original_snippet: &str) -> bool {
+    original_snippet
+        .lines()
+        .take(5) // looking for marker only in the beginning of the file
+        .any(|line| line.contains("@generated"))
+}
diff --git a/src/imports.rs b/src/imports.rs
index 64d78605f0c..5ac79936689 100644
--- a/src/imports.rs
+++ b/src/imports.rs
@@ -138,6 +138,29 @@ impl UseSegment {
         }
     }
 
+    // Check if self == other with their aliases removed.
+    fn equal_except_alias(&self, other: &Self) -> bool {
+        match (self, other) {
+            (UseSegment::Ident(ref s1, _), UseSegment::Ident(ref s2, _)) => s1 == s2,
+            (UseSegment::Slf(_), UseSegment::Slf(_))
+            | (UseSegment::Super(_), UseSegment::Super(_))
+            | (UseSegment::Crate(_), UseSegment::Crate(_))
+            | (UseSegment::Glob, UseSegment::Glob) => true,
+            (UseSegment::List(ref list1), UseSegment::List(ref list2)) => list1 == list2,
+            _ => false,
+        }
+    }
+
+    fn get_alias(&self) -> Option<&str> {
+        match self {
+            UseSegment::Ident(_, a)
+            | UseSegment::Slf(a)
+            | UseSegment::Super(a)
+            | UseSegment::Crate(a) => a.as_deref(),
+            _ => None,
+        }
+    }
+
     fn from_path_segment(
         context: &RewriteContext<'_>,
         path_seg: &ast::PathSegment,
@@ -558,6 +581,7 @@ impl UseTree {
                 SharedPrefix::Module => {
                     self.path[..self.path.len() - 1] == other.path[..other.path.len() - 1]
                 }
+                SharedPrefix::One => true,
             }
         }
     }
@@ -598,7 +622,7 @@ impl UseTree {
     fn merge(&mut self, other: &UseTree, merge_by: SharedPrefix) {
         let mut prefix = 0;
         for (a, b) in self.path.iter().zip(other.path.iter()) {
-            if *a == *b {
+            if a.equal_except_alias(b) {
                 prefix += 1;
             } else {
                 break;
@@ -633,14 +657,20 @@ fn merge_rest(
             return Some(new_path);
         }
     } else if len == 1 {
-        let rest = if a.len() == len { &b[1..] } else { &a[1..] };
-        return Some(vec![
-            b[0].clone(),
-            UseSegment::List(vec![
-                UseTree::from_path(vec![UseSegment::Slf(None)], DUMMY_SP),
-                UseTree::from_path(rest.to_vec(), DUMMY_SP),
-            ]),
-        ]);
+        let (common, rest) = if a.len() == len {
+            (&a[0], &b[1..])
+        } else {
+            (&b[0], &a[1..])
+        };
+        let mut list = vec![UseTree::from_path(
+            vec![UseSegment::Slf(common.get_alias().map(ToString::to_string))],
+            DUMMY_SP,
+        )];
+        match rest {
+            [UseSegment::List(rest_list)] => list.extend(rest_list.clone()),
+            _ => list.push(UseTree::from_path(rest.to_vec(), DUMMY_SP)),
+        }
+        return Some(vec![b[0].clone(), UseSegment::List(list)]);
     } else {
         len -= 1;
     }
@@ -655,18 +685,54 @@ fn merge_rest(
 }
 
 fn merge_use_trees_inner(trees: &mut Vec<UseTree>, use_tree: UseTree, merge_by: SharedPrefix) {
-    let similar_trees = trees
-        .iter_mut()
-        .filter(|tree| tree.share_prefix(&use_tree, merge_by));
+    struct SimilarTree<'a> {
+        similarity: usize,
+        path_len: usize,
+        tree: &'a mut UseTree,
+    }
+
+    let similar_trees = trees.iter_mut().filter_map(|tree| {
+        if tree.share_prefix(&use_tree, merge_by) {
+            // In the case of `SharedPrefix::One`, `similarity` is used for deciding with which
+            // tree `use_tree` should be merge.
+            // In other cases `similarity` won't be used, so set it to `0` as a dummy value.
+            let similarity = if merge_by == SharedPrefix::One {
+                tree.path
+                    .iter()
+                    .zip(&use_tree.path)
+                    .take_while(|(a, b)| a.equal_except_alias(b))
+                    .count()
+            } else {
+                0
+            };
+
+            let path_len = tree.path.len();
+            Some(SimilarTree {
+                similarity,
+                tree,
+                path_len,
+            })
+        } else {
+            None
+        }
+    });
+
     if use_tree.path.len() == 1 && merge_by == SharedPrefix::Crate {
-        if let Some(tree) = similar_trees.min_by_key(|tree| tree.path.len()) {
-            if tree.path.len() == 1 {
+        if let Some(tree) = similar_trees.min_by_key(|tree| tree.path_len) {
+            if tree.path_len == 1 {
+                return;
+            }
+        }
+    } else if merge_by == SharedPrefix::One {
+        if let Some(sim_tree) = similar_trees.max_by_key(|tree| tree.similarity) {
+            if sim_tree.similarity > 0 {
+                sim_tree.tree.merge(&use_tree, merge_by);
                 return;
             }
         }
-    } else if let Some(tree) = similar_trees.max_by_key(|tree| tree.path.len()) {
-        if tree.path.len() > 1 {
-            tree.merge(&use_tree, merge_by);
+    } else if let Some(sim_tree) = similar_trees.max_by_key(|tree| tree.path_len) {
+        if sim_tree.path_len > 1 {
+            sim_tree.tree.merge(&use_tree, merge_by);
             return;
         }
     }
@@ -880,6 +946,7 @@ impl Rewrite for UseTree {
 pub(crate) enum SharedPrefix {
     Crate,
     Module,
+    One,
 }
 
 #[cfg(test)]
@@ -904,7 +971,7 @@ mod test {
             }
 
             fn eat(&mut self, c: char) {
-                assert!(self.input.next().unwrap() == c);
+                assert_eq!(self.input.next().unwrap(), c);
             }
 
             fn push_segment(
@@ -1095,6 +1162,49 @@ mod test {
     }
 
     #[test]
+    fn test_use_tree_merge_one() {
+        test_merge!(One, ["a", "b"], ["{a, b}"]);
+
+        test_merge!(One, ["a::{aa, ab}", "b", "a"], ["{a::{self, aa, ab}, b}"]);
+
+        test_merge!(One, ["a as x", "b as y"], ["{a as x, b as y}"]);
+
+        test_merge!(
+            One,
+            ["a::{aa as xa, ab}", "b", "a"],
+            ["{a::{self, aa as xa, ab}, b}"]
+        );
+
+        test_merge!(
+            One,
+            ["a", "a::{aa, ab::{aba, abb}}"],
+            ["a::{self, aa, ab::{aba, abb}}"]
+        );
+
+        test_merge!(One, ["a", "b::{ba, *}"], ["{a, b::{ba, *}}"]);
+
+        test_merge!(One, ["a", "b", "a::aa"], ["{a::{self, aa}, b}"]);
+
+        test_merge!(
+            One,
+            ["a::aa::aaa", "a::ac::aca", "a::aa::*"],
+            ["a::{aa::{aaa, *}, ac::aca}"]
+        );
+
+        test_merge!(
+            One,
+            ["a", "b::{ba, bb}", "a::{aa::*, ab::aba}"],
+            ["{a::{self, aa::*, ab::aba}, b::{ba, bb}}"]
+        );
+
+        test_merge!(
+            One,
+            ["b", "a::ac::{aca, acb}", "a::{aa::*, ab}"],
+            ["{a::{aa::*, ab, ac::{aca, acb}}, b}"]
+        );
+    }
+
+    #[test]
     fn test_flatten_use_trees() {
         assert_eq!(
             flatten_use_trees(parse_use_trees!["foo::{a::{b, c}, d::e}"]),
diff --git a/src/items.rs b/src/items.rs
index 14041539b9d..1cb1a2701c3 100644
--- a/src/items.rs
+++ b/src/items.rs
@@ -174,14 +174,14 @@ pub(crate) struct FnSig<'a> {
     constness: ast::Const,
     defaultness: ast::Defaultness,
     unsafety: ast::Unsafe,
-    visibility: ast::Visibility,
+    visibility: &'a ast::Visibility,
 }
 
 impl<'a> FnSig<'a> {
     pub(crate) fn from_method_sig(
         method_sig: &'a ast::FnSig,
         generics: &'a ast::Generics,
-        visibility: ast::Visibility,
+        visibility: &'a ast::Visibility,
     ) -> FnSig<'a> {
         FnSig {
             unsafety: method_sig.header.unsafety,
@@ -204,7 +204,7 @@ impl<'a> FnSig<'a> {
         match *fn_kind {
             visit::FnKind::Fn(fn_ctxt, _, fn_sig, vis, _) => match fn_ctxt {
                 visit::FnCtxt::Assoc(..) => {
-                    let mut fn_sig = FnSig::from_method_sig(fn_sig, generics, vis.clone());
+                    let mut fn_sig = FnSig::from_method_sig(fn_sig, generics, vis);
                     fn_sig.defaultness = defaultness;
                     fn_sig
                 }
@@ -216,7 +216,7 @@ impl<'a> FnSig<'a> {
                     is_async: Cow::Borrowed(&fn_sig.header.asyncness),
                     defaultness,
                     unsafety: fn_sig.header.unsafety,
-                    visibility: vis.clone(),
+                    visibility: vis,
                 },
             },
             _ => unreachable!(),
@@ -323,6 +323,7 @@ impl<'a> FmtVisitor<'a> {
         indent: Indent,
         ident: symbol::Ident,
         sig: &ast::FnSig,
+        vis: &ast::Visibility,
         generics: &ast::Generics,
         span: Span,
     ) -> Option<String> {
@@ -334,7 +335,7 @@ impl<'a> FmtVisitor<'a> {
             &context,
             indent,
             ident,
-            &FnSig::from_method_sig(sig, generics, DEFAULT_VISIBILITY),
+            &FnSig::from_method_sig(sig, generics, vis),
             span,
             FnBraceStyle::None,
         )?;
@@ -1474,12 +1475,17 @@ fn format_tuple_struct(
         format_empty_struct_or_tuple(context, inner_span, offset, &mut result, "(", ")");
     } else {
         let shape = Shape::indented(offset, context.config).sub_width(1)?;
+        let lo = if let Some(generics) = struct_parts.generics {
+            generics.span.hi()
+        } else {
+            struct_parts.ident.span.hi()
+        };
         result = overflow::rewrite_with_parens(
             context,
             &result,
             fields.iter(),
             shape,
-            span,
+            mk_sp(lo, span.hi()),
             context.config.fn_call_width(),
             None,
         )?;
@@ -1503,7 +1509,7 @@ fn format_tuple_struct(
     Some(result)
 }
 
-fn rewrite_type<R: Rewrite>(
+pub(crate) fn rewrite_type<R: Rewrite>(
     context: &RewriteContext<'_>,
     indent: Indent,
     ident: symbol::Ident,
@@ -1760,7 +1766,7 @@ impl<'a> StaticParts<'a> {
         };
         StaticParts {
             prefix: "const",
-            vis: &DEFAULT_VISIBILITY,
+            vis: &ti.vis,
             ident: ti.ident,
             ty,
             mutability: ast::Mutability::Not,
@@ -1847,29 +1853,6 @@ fn rewrite_static(
         Some(format!("{}{};", prefix, ty_str))
     }
 }
-
-pub(crate) fn rewrite_type_alias(
-    ident: symbol::Ident,
-    ty_opt: Option<&ptr::P<ast::Ty>>,
-    generics: &ast::Generics,
-    generic_bounds_opt: Option<&ast::GenericBounds>,
-    context: &RewriteContext<'_>,
-    indent: Indent,
-    vis: &ast::Visibility,
-    span: Span,
-) -> Option<String> {
-    rewrite_type(
-        context,
-        indent,
-        ident,
-        vis,
-        generics,
-        generic_bounds_opt,
-        ty_opt,
-        span,
-    )
-}
-
 struct OpaqueType<'a> {
     bounds: &'a ast::GenericBounds,
 }
@@ -1883,32 +1866,7 @@ impl<'a> Rewrite for OpaqueType<'a> {
     }
 }
 
-pub(crate) fn rewrite_opaque_impl_type(
-    context: &RewriteContext<'_>,
-    ident: symbol::Ident,
-    generics: &ast::Generics,
-    generic_bounds: &ast::GenericBounds,
-    indent: Indent,
-) -> Option<String> {
-    let ident_str = rewrite_ident(context, ident);
-    // 5 = "type "
-    let generics_shape = Shape::indented(indent, context.config).offset_left(5)?;
-    let generics_str = rewrite_generics(context, ident_str, generics, generics_shape)?;
-    let prefix = format!("type {} =", generics_str);
-    let rhs = OpaqueType {
-        bounds: generic_bounds,
-    };
-
-    rewrite_assign_rhs(
-        context,
-        &prefix,
-        &rhs,
-        Shape::indented(indent, context.config).sub_width(1)?,
-    )
-    .map(|s| s + ";")
-}
-
-pub(crate) fn rewrite_associated_impl_type(
+pub(crate) fn rewrite_impl_type(
     ident: symbol::Ident,
     vis: &ast::Visibility,
     defaultness: ast::Defaultness,
@@ -1918,7 +1876,25 @@ pub(crate) fn rewrite_associated_impl_type(
     indent: Indent,
     span: Span,
 ) -> Option<String> {
-    let result = rewrite_type_alias(ident, ty_opt, generics, None, context, indent, vis, span)?;
+    // Opaque type
+    let result = if let Some(rustc_ast::ast::Ty {
+        kind: ast::TyKind::ImplTrait(_, ref bounds),
+        ..
+    }) = ty_opt.map(|t| &**t)
+    {
+        rewrite_type(
+            context,
+            indent,
+            ident,
+            &DEFAULT_VISIBILITY,
+            generics,
+            None,
+            Some(&OpaqueType { bounds }),
+            span,
+        )
+    } else {
+        rewrite_type(context, indent, ident, vis, generics, None, ty_opt, span)
+    }?;
 
     match defaultness {
         ast::Defaultness::Default(..) => Some(format!("default {}", result)),
@@ -1995,14 +1971,17 @@ impl Rewrite for ast::Param {
         let param_attrs_result = self
             .attrs
             .rewrite(context, Shape::legacy(shape.width, shape.indent))?;
-        let (span, has_multiple_attr_lines) = if !self.attrs.is_empty() {
+        // N.B. Doc comments aren't typically valid syntax, but could appear
+        // in the presence of certain macros - https://github.com/rust-lang/rustfmt/issues/4936
+        let (span, has_multiple_attr_lines, has_doc_comments) = if !self.attrs.is_empty() {
             let num_attrs = self.attrs.len();
             (
                 mk_sp(self.attrs[num_attrs - 1].span.hi(), self.pat.span.lo()),
                 param_attrs_result.contains('\n'),
+                self.attrs.iter().any(|a| a.is_doc_comment()),
             )
         } else {
-            (mk_sp(self.span.lo(), self.span.lo()), false)
+            (mk_sp(self.span.lo(), self.span.lo()), false, false)
         };
 
         if let Some(ref explicit_self) = self.to_self() {
@@ -2015,15 +1994,16 @@ impl Rewrite for ast::Param {
                 has_multiple_attr_lines,
             )
         } else if is_named_param(self) {
+            let param_name = &self
+                .pat
+                .rewrite(context, Shape::legacy(shape.width, shape.indent))?;
             let mut result = combine_strs_with_missing_comments(
                 context,
                 &param_attrs_result,
-                &self
-                    .pat
-                    .rewrite(context, Shape::legacy(shape.width, shape.indent))?,
+                param_name,
                 span,
                 shape,
-                !has_multiple_attr_lines,
+                !has_multiple_attr_lines && !has_doc_comments,
             )?;
 
             if !is_empty_infer(&*self.ty, self.pat.span) {
@@ -2034,10 +2014,30 @@ impl Rewrite for ast::Param {
                 result.push_str(&after_comment);
                 let overhead = last_line_width(&result);
                 let max_width = shape.width.checked_sub(overhead)?;
-                let ty_str = self
+                if let Some(ty_str) = self
                     .ty
-                    .rewrite(context, Shape::legacy(max_width, shape.indent))?;
-                result.push_str(&ty_str);
+                    .rewrite(context, Shape::legacy(max_width, shape.indent))
+                {
+                    result.push_str(&ty_str);
+                } else {
+                    result = combine_strs_with_missing_comments(
+                        context,
+                        &(param_attrs_result + &shape.to_string_with_newline(context.config)),
+                        param_name,
+                        span,
+                        shape,
+                        !has_multiple_attr_lines,
+                    )?;
+                    result.push_str(&before_comment);
+                    result.push_str(colon_spaces(context.config));
+                    result.push_str(&after_comment);
+                    let overhead = last_line_width(&result);
+                    let max_width = shape.width.checked_sub(overhead)?;
+                    let ty_str = self
+                        .ty
+                        .rewrite(context, Shape::legacy(max_width, shape.indent))?;
+                    result.push_str(&ty_str);
+                }
             }
 
             Some(result)
@@ -3146,7 +3146,7 @@ impl Rewrite for ast::ForeignItem {
                         context,
                         shape.indent,
                         self.ident,
-                        &FnSig::from_method_sig(&fn_sig, generics, self.vis.clone()),
+                        &FnSig::from_method_sig(&fn_sig, generics, &self.vis),
                         span,
                         FnBraceStyle::None,
                     )
@@ -3170,14 +3170,14 @@ impl Rewrite for ast::ForeignItem {
             ast::ForeignItemKind::TyAlias(ref ty_alias_kind) => {
                 let ast::TyAliasKind(_, ref generics, ref generic_bounds, ref type_default) =
                     **ty_alias_kind;
-                rewrite_type_alias(
-                    self.ident,
-                    type_default.as_ref(),
-                    generics,
-                    Some(generic_bounds),
+                rewrite_type(
                     &context,
                     shape.indent,
+                    self.ident,
                     &self.vis,
+                    generics,
+                    Some(generic_bounds),
+                    type_default.as_ref(),
                     self.span,
                 )
             }
diff --git a/src/lists.rs b/src/lists.rs
index 73e886c5563..c04b4787616 100644
--- a/src/lists.rs
+++ b/src/lists.rs
@@ -367,9 +367,9 @@ where
             result.push_str(&comment);
 
             if !inner_item.is_empty() {
-                if tactic == DefinitiveListTactic::Vertical || tactic == DefinitiveListTactic::Mixed
-                {
-                    // We cannot keep pre-comments on the same line if the comment if normalized.
+                use DefinitiveListTactic::*;
+                if matches!(tactic, Vertical | Mixed | SpecialMacro(_)) {
+                    // We cannot keep pre-comments on the same line if the comment is normalized.
                     let keep_comment = if formatting.config.normalize_comments()
                         || item.pre_comment_style == ListItemCommentStyle::DifferentLine
                     {
@@ -389,7 +389,7 @@ where
                         line_len = item.item.as_ref().map_or(0, |s| unicode_str_width(&s));
                     }
                 } else {
-                    result.push(' ');
+                    result.push(' ')
                 }
             }
             item_max_width = None;
diff --git a/src/matches.rs b/src/matches.rs
index 140ec226c02..5a6ed0ec06e 100644
--- a/src/matches.rs
+++ b/src/matches.rs
@@ -409,6 +409,7 @@ fn rewrite_match_body(
             }
             result.push_str(&nested_indent_str);
             result.push_str(&body_str);
+            result.push_str(&comma);
             return Some(result);
         }
 
diff --git a/src/missed_spans.rs b/src/missed_spans.rs
index 263d840785a..28edcb784b4 100644
--- a/src/missed_spans.rs
+++ b/src/missed_spans.rs
@@ -51,6 +51,14 @@ impl<'a> FmtVisitor<'a> {
     }
 
     pub(crate) fn format_missing_with_indent(&mut self, end: BytePos) {
+        self.format_missing_indent(end, true)
+    }
+
+    pub(crate) fn format_missing_no_indent(&mut self, end: BytePos) {
+        self.format_missing_indent(end, false)
+    }
+
+    fn format_missing_indent(&mut self, end: BytePos, should_indent: bool) {
         let config = self.config;
         self.format_missing_inner(end, |this, last_snippet, snippet| {
             this.push_str(last_snippet.trim_end());
@@ -58,14 +66,10 @@ impl<'a> FmtVisitor<'a> {
                 // No new lines in the snippet.
                 this.push_str("\n");
             }
-            let indent = this.block_indent.to_string(config);
-            this.push_str(&indent);
-        })
-    }
-
-    pub(crate) fn format_missing_no_indent(&mut self, end: BytePos) {
-        self.format_missing_inner(end, |this, last_snippet, _| {
-            this.push_str(last_snippet.trim_end());
+            if should_indent {
+                let indent = this.block_indent.to_string(config);
+                this.push_str(&indent);
+            }
         })
     }
 
diff --git a/src/overflow.rs b/src/overflow.rs
index e32213467a5..ac24181c780 100644
--- a/src/overflow.rs
+++ b/src/overflow.rs
@@ -77,6 +77,7 @@ pub(crate) enum OverflowableItem<'a> {
     FieldDef(&'a ast::FieldDef),
     TuplePatField(&'a TuplePatField<'a>),
     Ty(&'a ast::Ty),
+    Pat(&'a ast::Pat),
 }
 
 impl<'a> Rewrite for OverflowableItem<'a> {
@@ -116,6 +117,7 @@ impl<'a> OverflowableItem<'a> {
             OverflowableItem::FieldDef(sf) => f(*sf),
             OverflowableItem::TuplePatField(pat) => f(*pat),
             OverflowableItem::Ty(ty) => f(*ty),
+            OverflowableItem::Pat(pat) => f(*pat),
         }
     }
 
@@ -232,7 +234,7 @@ macro_rules! impl_into_overflowable_item_for_rustfmt_types {
     }
 }
 
-impl_into_overflowable_item_for_ast_node!(Expr, GenericParam, NestedMetaItem, FieldDef, Ty);
+impl_into_overflowable_item_for_ast_node!(Expr, GenericParam, NestedMetaItem, FieldDef, Ty, Pat);
 impl_into_overflowable_item_for_rustfmt_types!([MacroArg], [SegmentParam, TuplePatField]);
 
 pub(crate) fn into_overflowable_list<'a, T>(
diff --git a/src/patterns.rs b/src/patterns.rs
index 0501e76d277..ba8d8024a97 100644
--- a/src/patterns.rs
+++ b/src/patterns.rs
@@ -4,6 +4,7 @@ use rustc_span::{BytePos, Span};
 
 use crate::comment::{combine_strs_with_missing_comments, FindUncommented};
 use crate::config::lists::*;
+use crate::config::Version;
 use crate::expr::{can_be_overflowed_expr, rewrite_unary_prefix, wrap_struct_field};
 use crate::lists::{
     definitive_tactic, itemize_list, shape_for_tactic, struct_lit_formatting, struct_lit_shape,
@@ -226,12 +227,13 @@ impl Rewrite for Pat {
             PatKind::Path(ref q_self, ref path) => {
                 rewrite_path(context, PathContext::Expr, q_self.as_ref(), path, shape)
             }
-            PatKind::TupleStruct(_, ref path, ref pat_vec) => {
-                let path_str = rewrite_path(context, PathContext::Expr, None, path, shape)?;
+            PatKind::TupleStruct(ref q_self, ref path, ref pat_vec) => {
+                let path_str =
+                    rewrite_path(context, PathContext::Expr, q_self.as_ref(), path, shape)?;
                 rewrite_tuple_pat(pat_vec, Some(path_str), self.span, context, shape)
             }
             PatKind::Lit(ref expr) => expr.rewrite(context, shape),
-            PatKind::Slice(ref slice_pat) => {
+            PatKind::Slice(ref slice_pat) if context.config.version() == Version::One => {
                 let rw: Vec<String> = slice_pat
                     .iter()
                     .map(|p| {
@@ -244,8 +246,17 @@ impl Rewrite for Pat {
                     .collect();
                 Some(format!("[{}]", rw.join(", ")))
             }
-            PatKind::Struct(_, ref path, ref fields, ellipsis) => {
-                rewrite_struct_pat(path, fields, ellipsis, self.span, context, shape)
+            PatKind::Slice(ref slice_pat) => overflow::rewrite_with_square_brackets(
+                context,
+                "",
+                slice_pat.iter(),
+                shape,
+                self.span,
+                None,
+                None,
+            ),
+            PatKind::Struct(ref qself, ref path, ref fields, ellipsis) => {
+                rewrite_struct_pat(qself, path, fields, ellipsis, self.span, context, shape)
             }
             PatKind::MacCall(ref mac) => {
                 rewrite_macro(mac, None, context, shape, MacroPosition::Pat)
@@ -258,6 +269,7 @@ impl Rewrite for Pat {
 }
 
 fn rewrite_struct_pat(
+    qself: &Option<ast::QSelf>,
     path: &ast::Path,
     fields: &[ast::PatField],
     ellipsis: bool,
@@ -267,7 +279,7 @@ fn rewrite_struct_pat(
 ) -> Option<String> {
     // 2 =  ` {`
     let path_shape = shape.sub_width(2)?;
-    let path_str = rewrite_path(context, PathContext::Expr, None, path, path_shape)?;
+    let path_str = rewrite_path(context, PathContext::Expr, qself.as_ref(), path, path_shape)?;
 
     if fields.is_empty() && !ellipsis {
         return Some(format!("{} {{}}", path_str));
diff --git a/src/reorder.rs b/src/reorder.rs
index ac65ff2c108..2c58350d4fe 100644
--- a/src/reorder.rs
+++ b/src/reorder.rs
@@ -113,6 +113,7 @@ fn rewrite_reorderable_or_regroupable_items(
                     merge_use_trees(normalized_items, SharedPrefix::Module)
                 }
                 ImportGranularity::Item => flatten_use_trees(normalized_items),
+                ImportGranularity::One => merge_use_trees(normalized_items, SharedPrefix::One),
                 ImportGranularity::Preserve => normalized_items,
             };
 
diff --git a/src/spanned.rs b/src/spanned.rs
index 7e3786b7cd9..8e6c75a3744 100644
--- a/src/spanned.rs
+++ b/src/spanned.rs
@@ -104,7 +104,7 @@ impl Spanned for ast::Arm {
 impl Spanned for ast::Param {
     fn span(&self) -> Span {
         if crate::items::is_named_param(self) {
-            mk_sp(self.pat.span.lo(), self.ty.span.hi())
+            mk_sp(crate::items::span_lo_for_param(self), self.ty.span.hi())
         } else {
             self.ty.span
         }
diff --git a/src/syntux/session.rs b/src/syntux/session.rs
index 2965b0928aa..946c076d9f2 100644
--- a/src/syntux/session.rs
+++ b/src/syntux/session.rs
@@ -175,6 +175,12 @@ impl ParseSess {
         self.parse_sess.source_map().span_to_filename(span).into()
     }
 
+    pub(crate) fn span_to_file_contents(&self, span: Span) -> Lrc<rustc_span::SourceFile> {
+        self.parse_sess
+            .source_map()
+            .lookup_source_file(span.data().lo)
+    }
+
     pub(crate) fn span_to_first_line_string(&self, span: Span) -> String {
         let file_lines = self.parse_sess.source_map().span_to_lines(span).ok();
 
diff --git a/src/test/mod.rs b/src/test/mod.rs
index cb52346a13a..48d61289a9b 100644
--- a/src/test/mod.rs
+++ b/src/test/mod.rs
@@ -469,11 +469,6 @@ fn stdin_works_with_modified_lines() {
 #[test]
 fn stdin_disable_all_formatting_test() {
     init_log();
-    match option_env!("CFG_RELEASE_CHANNEL") {
-        None | Some("nightly") => {}
-        // These tests require nightly.
-        _ => return,
-    }
     let input = String::from("fn main() { println!(\"This should not be formatted.\"); }");
     let mut child = Command::new(rustfmt().to_str().unwrap())
         .stdin(Stdio::piped())
@@ -694,7 +689,7 @@ fn read_significant_comments(file_name: &Path) -> HashMap<String, String> {
     reader
         .lines()
         .map(|line| line.expect("failed getting line"))
-        .take_while(|line| line_regex.is_match(line))
+        .filter(|line| line_regex.is_match(line))
         .filter_map(|line| {
             regex.captures_iter(&line).next().map(|capture| {
                 (
diff --git a/src/types.rs b/src/types.rs
index 76bf58e875b..62c05ba078c 100644
--- a/src/types.rs
+++ b/src/types.rs
@@ -169,31 +169,38 @@ impl<'a> Rewrite for SegmentParam<'a> {
             SegmentParam::Const(const_) => const_.rewrite(context, shape),
             SegmentParam::LifeTime(lt) => lt.rewrite(context, shape),
             SegmentParam::Type(ty) => ty.rewrite(context, shape),
-            SegmentParam::Binding(assoc_ty_constraint) => {
-                let mut result = match assoc_ty_constraint.kind {
-                    ast::AssocTyConstraintKind::Bound { .. } => {
-                        format!("{}: ", rewrite_ident(context, assoc_ty_constraint.ident))
-                    }
-                    ast::AssocTyConstraintKind::Equality { .. } => {
-                        match context.config.type_punctuation_density() {
-                            TypeDensity::Wide => {
-                                format!("{} = ", rewrite_ident(context, assoc_ty_constraint.ident))
-                            }
-                            TypeDensity::Compressed => {
-                                format!("{}=", rewrite_ident(context, assoc_ty_constraint.ident))
-                            }
-                        }
-                    }
-                };
+            SegmentParam::Binding(atc) => atc.rewrite(context, shape),
+        }
+    }
+}
 
-                let budget = shape.width.checked_sub(result.len())?;
-                let rewrite = assoc_ty_constraint
-                    .kind
-                    .rewrite(context, Shape::legacy(budget, shape.indent + result.len()))?;
-                result.push_str(&rewrite);
-                Some(result)
-            }
+impl Rewrite for ast::AssocTyConstraint {
+    fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
+        use ast::AssocTyConstraintKind::{Bound, Equality};
+
+        let mut result = String::with_capacity(128);
+        result.push_str(rewrite_ident(context, self.ident));
+
+        if let Some(ref gen_args) = self.gen_args {
+            let budget = shape.width.checked_sub(result.len())?;
+            let shape = Shape::legacy(budget, shape.indent + result.len());
+            let gen_str = rewrite_generic_args(gen_args, context, shape, gen_args.span())?;
+            result.push_str(&gen_str);
         }
+
+        let infix = match (&self.kind, context.config.type_punctuation_density()) {
+            (Bound { .. }, _) => ": ",
+            (Equality { .. }, TypeDensity::Wide) => " = ",
+            (Equality { .. }, TypeDensity::Compressed) => "=",
+        };
+        result.push_str(infix);
+
+        let budget = shape.width.checked_sub(result.len())?;
+        let shape = Shape::legacy(budget, shape.indent + result.len());
+        let rewrite = self.kind.rewrite(context, shape)?;
+        result.push_str(&rewrite);
+
+        Some(result)
     }
 }
 
@@ -235,21 +242,9 @@ fn rewrite_segment(
     };
 
     if let Some(ref args) = segment.args {
+        let generics_str = rewrite_generic_args(args, context, shape, mk_sp(*span_lo, span_hi))?;
         match **args {
             ast::GenericArgs::AngleBracketed(ref data) if !data.args.is_empty() => {
-                let param_list = data
-                    .args
-                    .iter()
-                    .map(|x| match x {
-                        ast::AngleBracketedArg::Arg(generic_arg) => {
-                            SegmentParam::from_generic_arg(generic_arg)
-                        }
-                        ast::AngleBracketedArg::Constraint(constraint) => {
-                            SegmentParam::Binding(constraint)
-                        }
-                    })
-                    .collect::<Vec<_>>();
-
                 // HACK: squeeze out the span between the identifier and the parameters.
                 // The hack is requried so that we don't remove the separator inside macro calls.
                 // This does not work in the presence of comment, hoping that people are
@@ -265,33 +260,14 @@ fn rewrite_segment(
                 };
                 result.push_str(separator);
 
-                let generics_str = overflow::rewrite_with_angle_brackets(
-                    context,
-                    "",
-                    param_list.iter(),
-                    shape,
-                    mk_sp(*span_lo, span_hi),
-                )?;
-
                 // Update position of last bracket.
                 *span_lo = context
                     .snippet_provider
                     .span_after(mk_sp(*span_lo, span_hi), "<");
-
-                result.push_str(&generics_str)
-            }
-            ast::GenericArgs::Parenthesized(ref data) => {
-                result.push_str(&format_function_type(
-                    data.inputs.iter().map(|x| &**x),
-                    &data.output,
-                    false,
-                    data.span,
-                    context,
-                    shape,
-                )?);
             }
             _ => (),
         }
+        result.push_str(&generics_str)
     }
 
     Some(result)
@@ -484,6 +460,41 @@ impl Rewrite for ast::GenericArg {
     }
 }
 
+fn rewrite_generic_args(
+    gen_args: &ast::GenericArgs,
+    context: &RewriteContext<'_>,
+    shape: Shape,
+    span: Span,
+) -> Option<String> {
+    match gen_args {
+        ast::GenericArgs::AngleBracketed(ref data) if !data.args.is_empty() => {
+            let args = data
+                .args
+                .iter()
+                .map(|x| match x {
+                    ast::AngleBracketedArg::Arg(generic_arg) => {
+                        SegmentParam::from_generic_arg(generic_arg)
+                    }
+                    ast::AngleBracketedArg::Constraint(constraint) => {
+                        SegmentParam::Binding(constraint)
+                    }
+                })
+                .collect::<Vec<_>>();
+
+            overflow::rewrite_with_angle_brackets(context, "", args.iter(), shape, span)
+        }
+        ast::GenericArgs::Parenthesized(ref data) => format_function_type(
+            data.inputs.iter().map(|x| &**x),
+            &data.output,
+            false,
+            data.span,
+            context,
+            shape,
+        ),
+        _ => Some("".to_owned()),
+    }
+}
+
 fn rewrite_bounded_lifetime(
     lt: &ast::Lifetime,
     bounds: &[ast::GenericBound],
@@ -566,13 +577,23 @@ impl Rewrite for ast::GenericParam {
         if let ast::GenericParamKind::Const {
             ref ty,
             kw_span: _,
-            default: _,
+            default,
         } = &self.kind
         {
             result.push_str("const ");
             result.push_str(rewrite_ident(context, self.ident));
             result.push_str(": ");
             result.push_str(&ty.rewrite(context, shape)?);
+            if let Some(default) = default {
+                let eq_str = match context.config.type_punctuation_density() {
+                    TypeDensity::Compressed => "=",
+                    TypeDensity::Wide => " = ",
+                };
+                result.push_str(eq_str);
+                let budget = shape.width.checked_sub(result.len())?;
+                let rewrite = default.rewrite(context, Shape::legacy(budget, shape.indent))?;
+                result.push_str(&rewrite);
+            }
         } else {
             result.push_str(rewrite_ident(context, self.ident));
         }
diff --git a/src/visitor.rs b/src/visitor.rs
index 770693d165b..d854d90b40b 100644
--- a/src/visitor.rs
+++ b/src/visitor.rs
@@ -3,7 +3,7 @@ use std::rc::Rc;
 
 use rustc_ast::{ast, token::DelimToken, visit, AstLike};
 use rustc_data_structures::sync::Lrc;
-use rustc_span::{symbol, BytePos, Pos, Span, DUMMY_SP};
+use rustc_span::{symbol, BytePos, Pos, Span};
 
 use crate::attr::*;
 use crate::comment::{contains_comment, rewrite_comment, CodeCharKind, CommentCodeSlices};
@@ -11,9 +11,9 @@ use crate::config::Version;
 use crate::config::{BraceStyle, Config};
 use crate::coverage::transform_missing_snippet;
 use crate::items::{
-    format_impl, format_trait, format_trait_alias, is_mod_decl, is_use_item,
-    rewrite_associated_impl_type, rewrite_extern_crate, rewrite_opaque_impl_type,
-    rewrite_opaque_type, rewrite_type_alias, FnBraceStyle, FnSig, StaticParts, StructParts,
+    format_impl, format_trait, format_trait_alias, is_mod_decl, is_use_item, rewrite_extern_crate,
+    rewrite_impl_type, rewrite_opaque_type, rewrite_type, FnBraceStyle, FnSig, StaticParts,
+    StructParts,
 };
 use crate::macros::{macro_style, rewrite_macro, rewrite_macro_def, MacroPosition};
 use crate::modules::Module;
@@ -568,6 +568,7 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                             indent,
                             item.ident,
                             &fn_signature,
+                            &item.vis,
                             generics,
                             item.span,
                         );
@@ -579,14 +580,14 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                         **alias_kind;
                     match ty {
                         Some(ty) => {
-                            let rewrite = rewrite_type_alias(
-                                item.ident,
-                                Some(&*ty),
-                                generics,
-                                Some(generic_bounds),
+                            let rewrite = rewrite_type(
                                 &self.get_context(),
                                 self.block_indent,
+                                item.ident,
                                 &item.vis,
+                                generics,
+                                Some(generic_bounds),
+                                Some(&*ty),
                                 item.span,
                             );
                             self.push_rewrite(item.span, rewrite);
@@ -641,14 +642,9 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                 let ast::FnKind(defaultness, ref sig, ref generics, ref block) = **fn_kind;
                 if let Some(ref body) = block {
                     let inner_attrs = inner_attributes(&ti.attrs);
-                    let vis = ast::Visibility {
-                        kind: ast::VisibilityKind::Inherited,
-                        span: DUMMY_SP,
-                        tokens: None,
-                    };
                     let fn_ctxt = visit::FnCtxt::Assoc(visit::AssocCtxt::Trait);
                     self.visit_fn(
-                        visit::FnKind::Fn(fn_ctxt, ti.ident, sig, &vis, Some(body)),
+                        visit::FnKind::Fn(fn_ctxt, ti.ident, sig, &ti.vis, Some(body)),
                         generics,
                         &sig.decl,
                         ti.span,
@@ -658,21 +654,21 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                 } else {
                     let indent = self.block_indent;
                     let rewrite =
-                        self.rewrite_required_fn(indent, ti.ident, sig, generics, ti.span);
+                        self.rewrite_required_fn(indent, ti.ident, sig, &ti.vis, generics, ti.span);
                     self.push_rewrite(ti.span, rewrite);
                 }
             }
             ast::AssocItemKind::TyAlias(ref ty_alias_kind) => {
                 let ast::TyAliasKind(_, ref generics, ref generic_bounds, ref type_default) =
                     **ty_alias_kind;
-                let rewrite = rewrite_type_alias(
-                    ti.ident,
-                    type_default.as_ref(),
-                    generics,
-                    Some(generic_bounds),
+                let rewrite = rewrite_type(
                     &self.get_context(),
                     self.block_indent,
+                    ti.ident,
                     &ti.vis,
+                    generics,
+                    Some(generic_bounds),
+                    type_default.as_ref(),
                     ti.span,
                 );
                 self.push_rewrite(ti.span, rewrite);
@@ -708,15 +704,16 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                 } else {
                     let indent = self.block_indent;
                     let rewrite =
-                        self.rewrite_required_fn(indent, ii.ident, sig, generics, ii.span);
+                        self.rewrite_required_fn(indent, ii.ident, sig, &ii.vis, generics, ii.span);
                     self.push_rewrite(ii.span, rewrite);
                 }
             }
             ast::AssocItemKind::Const(..) => self.visit_static(&StaticParts::from_impl_item(ii)),
             ast::AssocItemKind::TyAlias(ref ty_alias_kind) => {
                 let ast::TyAliasKind(defaultness, ref generics, _, ref ty) = **ty_alias_kind;
-                let rewrite_associated = || {
-                    rewrite_associated_impl_type(
+                self.push_rewrite(
+                    ii.span,
+                    rewrite_impl_type(
                         ii.ident,
                         &ii.vis,
                         defaultness,
@@ -725,22 +722,8 @@ impl<'b, 'a: 'b> FmtVisitor<'a> {
                         &self.get_context(),
                         self.block_indent,
                         ii.span,
-                    )
-                };
-                let rewrite = match ty {
-                    None => rewrite_associated(),
-                    Some(ty) => match ty.kind {
-                        ast::TyKind::ImplTrait(_, ref bounds) => rewrite_opaque_impl_type(
-                            &self.get_context(),
-                            ii.ident,
-                            generics,
-                            bounds,
-                            self.block_indent,
-                        ),
-                        _ => rewrite_associated(),
-                    },
-                };
-                self.push_rewrite(ii.span, rewrite);
+                    ),
+                );
             }
             ast::AssocItemKind::MacCall(ref mac) => {
                 self.visit_mac(mac, Some(ii.ident), MacroPosition::Item);