//!
//! `mod`, `extern crate` and `use` declarations are reorderd in alphabetical
//! order. Trait items are reordered in pre-determined order (associated types
-//! and constatns comes before methods).
+//! and constants comes before methods).
-// TODO(#2455): Reorder trait items.
+// FIXME(#2455): Reorder trait items.
-use config::{Config, lists::*};
-use syntax::ast::UseTreeKind;
-use syntax::{ast, attr, codemap::Span};
+use config::Config;
+use syntax::{ast, attr, source_map::Span};
use attr::filter_inline_attrs;
-use codemap::LineRangeUtils;
use comment::combine_strs_with_missing_comments;
-use imports::{path_to_imported_ident, rewrite_import};
+use imports::{merge_use_trees, UseTree};
use items::{is_mod_decl, rewrite_extern_crate, rewrite_mod};
-use lists::{itemize_list, write_list, ListFormatting};
+use lists::{itemize_list, write_list, ListFormatting, ListItem};
use rewrite::{Rewrite, RewriteContext};
use shape::Shape;
+use source_map::LineRangeUtils;
use spanned::Spanned;
use utils::mk_sp;
use visitor::FmtVisitor;
-use std::cmp::{Ord, Ordering, PartialOrd};
-
-fn compare_use_trees(a: &ast::UseTree, b: &ast::UseTree) -> Ordering {
- let aa = UseTree::from_ast(a).normalize();
- let bb = UseTree::from_ast(b).normalize();
- aa.cmp(&bb)
-}
+use std::cmp::{Ord, Ordering};
/// Choose the ordering between the given two items.
fn compare_items(a: &ast::Item, b: &ast::Item) -> Ordering {
(&ast::ItemKind::Mod(..), &ast::ItemKind::Mod(..)) => {
a.ident.name.as_str().cmp(&b.ident.name.as_str())
}
- (&ast::ItemKind::Use(ref a_tree), &ast::ItemKind::Use(ref b_tree)) => {
- compare_use_trees(a_tree, b_tree)
- }
(&ast::ItemKind::ExternCrate(ref a_name), &ast::ItemKind::ExternCrate(ref b_name)) => {
// `extern crate foo as bar;`
// ^^^ Comparing this.
}
}
+fn wrap_reorderable_items(
+ context: &RewriteContext,
+ list_items: &[ListItem],
+ shape: Shape,
+) -> Option<String> {
+ let fmt = ListFormatting::new(shape, context.config).separator("");
+ write_list(list_items, &fmt)
+}
+
+fn rewrite_reorderable_item(
+ context: &RewriteContext,
+ item: &ast::Item,
+ shape: Shape,
+) -> Option<String> {
+ let attrs = filter_inline_attrs(&item.attrs, item.span());
+ let attrs_str = attrs.rewrite(context, shape)?;
+
+ let missed_span = if attrs.is_empty() {
+ mk_sp(item.span.lo(), item.span.lo())
+ } else {
+ mk_sp(attrs.last().unwrap().span.hi(), item.span.lo())
+ };
+
+ let item_str = match item.node {
+ ast::ItemKind::ExternCrate(..) => rewrite_extern_crate(context, item)?,
+ ast::ItemKind::Mod(..) => rewrite_mod(context, item),
+ _ => return None,
+ };
+
+ combine_strs_with_missing_comments(context, &attrs_str, &item_str, missed_span, shape, false)
+}
+
/// Rewrite a list of items with reordering. Every item in `items` must have
/// the same `ast::ItemKind`.
fn rewrite_reorderable_items(
shape: Shape,
span: Span,
) -> Option<String> {
- let items = itemize_list(
- context.snippet_provider,
- reorderable_items.iter(),
- "",
- ";",
- |item| item.span().lo(),
- |item| item.span().hi(),
- |item| {
- let attrs = filter_inline_attrs(&item.attrs, item.span());
- let attrs_str = attrs.rewrite(context, shape)?;
-
- let missed_span = if attrs.is_empty() {
- mk_sp(item.span.lo(), item.span.lo())
- } else {
- mk_sp(attrs.last().unwrap().span.hi(), item.span.lo())
- };
-
- let item_str = match item.node {
- ast::ItemKind::Use(ref tree) => {
- rewrite_import(context, &item.vis, tree, &item.attrs, shape)?
- }
- ast::ItemKind::ExternCrate(..) => rewrite_extern_crate(context, item)?,
- ast::ItemKind::Mod(..) => rewrite_mod(item),
- _ => return None,
- };
-
- combine_strs_with_missing_comments(
- context,
- &attrs_str,
- &item_str,
- missed_span,
- shape,
+ match reorderable_items[0].node {
+ // FIXME: Remove duplicated code.
+ ast::ItemKind::Use(..) => {
+ let mut normalized_items: Vec<_> = reorderable_items
+ .iter()
+ .filter_map(|item| UseTree::from_ast_with_normalization(context, item))
+ .collect();
+ let cloned = normalized_items.clone();
+ // Add comments before merging.
+ let list_items = itemize_list(
+ context.snippet_provider,
+ cloned.iter(),
+ "",
+ ";",
+ |item| item.span().lo(),
+ |item| item.span().hi(),
+ |_item| Some("".to_owned()),
+ span.lo(),
+ span.hi(),
false,
- )
- },
- span.lo(),
- span.hi(),
- false,
- );
-
- let mut item_pair_vec: Vec<_> = items.zip(reorderable_items.iter()).collect();
- item_pair_vec.sort_by(|a, b| compare_items(a.1, b.1));
- let item_vec: Vec<_> = item_pair_vec.into_iter().map(|pair| pair.0).collect();
+ );
+ for (item, list_item) in normalized_items.iter_mut().zip(list_items) {
+ item.list_item = Some(list_item.clone());
+ }
+ if context.config.merge_imports() {
+ normalized_items = merge_use_trees(normalized_items);
+ }
+ normalized_items.sort();
+
+ // 4 = "use ", 1 = ";"
+ let nested_shape = shape.offset_left(4)?.sub_width(1)?;
+ let item_vec: Vec<_> = normalized_items
+ .into_iter()
+ .map(|use_tree| ListItem {
+ item: use_tree.rewrite_top_level(context, nested_shape),
+ ..use_tree.list_item.unwrap_or_else(ListItem::empty)
+ }).collect();
+
+ wrap_reorderable_items(context, &item_vec, nested_shape)
+ }
+ _ => {
+ let list_items = itemize_list(
+ context.snippet_provider,
+ reorderable_items.iter(),
+ "",
+ ";",
+ |item| item.span().lo(),
+ |item| item.span().hi(),
+ |item| rewrite_reorderable_item(context, item, shape),
+ span.lo(),
+ span.hi(),
+ false,
+ );
- let fmt = ListFormatting {
- tactic: DefinitiveListTactic::Vertical,
- separator: "",
- trailing_separator: SeparatorTactic::Never,
- separator_place: SeparatorPlace::Back,
- shape,
- ends_with_newline: true,
- preserve_newline: false,
- config: context.config,
- };
+ let mut item_pair_vec: Vec<_> = list_items.zip(reorderable_items.iter()).collect();
+ item_pair_vec.sort_by(|a, b| compare_items(a.1, b.1));
+ let item_vec: Vec<_> = item_pair_vec.into_iter().map(|pair| pair.0).collect();
- write_list(&item_vec, &fmt)
+ wrap_reorderable_items(context, &item_vec, shape)
+ }
+ }
}
fn contains_macro_use_attr(item: &ast::Item) -> bool {
}
impl ReorderableItemKind {
- pub fn from(item: &ast::Item) -> Self {
+ fn from(item: &ast::Item) -> Self {
match item.node {
_ if contains_macro_use_attr(item) => ReorderableItemKind::Other,
ast::ItemKind::ExternCrate(..) => ReorderableItemKind::ExternCrate,
}
}
- pub fn is_same_item_kind(&self, item: &ast::Item) -> bool {
- ReorderableItemKind::from(item) == *self
+ fn is_same_item_kind(self, item: &ast::Item) -> bool {
+ ReorderableItemKind::from(item) == self
}
- pub fn is_reorderable(&self, config: &Config) -> bool {
- match *self {
- ReorderableItemKind::ExternCrate => config.reorder_extern_crates(),
+ fn is_reorderable(self, config: &Config) -> bool {
+ match self {
+ ReorderableItemKind::ExternCrate => config.reorder_imports(),
ReorderableItemKind::Mod => config.reorder_modules(),
ReorderableItemKind::Use => config.reorder_imports(),
ReorderableItemKind::Other => false,
}
}
- pub fn in_group(&self, config: &Config) -> bool {
- match *self {
- ReorderableItemKind::ExternCrate => config.reorder_extern_crates_in_group(),
- ReorderableItemKind::Mod => config.reorder_modules(),
- ReorderableItemKind::Use => config.reorder_imports_in_group(),
+ fn in_group(self) -> bool {
+ match self {
+ ReorderableItemKind::ExternCrate
+ | ReorderableItemKind::Mod
+ | ReorderableItemKind::Use => true,
ReorderableItemKind::Other => false,
}
}
item_kind: ReorderableItemKind,
in_group: bool,
) -> usize {
- let mut last = self.codemap.lookup_line_range(items[0].span());
+ let mut last = self.source_map.lookup_line_range(items[0].span());
let item_length = items
.iter()
.take_while(|ppi| {
- item_kind.is_same_item_kind(&***ppi) && (!in_group || {
- let current = self.codemap.lookup_line_range(ppi.span());
- let in_same_group = current.lo < last.hi + 2;
- last = current;
- in_same_group
- })
- })
- .count();
+ item_kind.is_same_item_kind(&***ppi)
+ && (!in_group || {
+ let current = self.source_map.lookup_line_range(ppi.span());
+ let in_same_group = current.lo < last.hi + 2;
+ last = current;
+ in_same_group
+ })
+ }).count();
let items = &items[..item_length];
let at_least_one_in_file_lines = items
let item_kind = ReorderableItemKind::from(items[0]);
if item_kind.is_reorderable(self.config) {
let visited_items_num =
- self.walk_reorderable_items(items, item_kind, item_kind.in_group(self.config));
+ self.walk_reorderable_items(items, item_kind, item_kind.in_group());
let (_, rest) = items.split_at(visited_items_num);
items = rest;
} else {
}
}
}
-
-// Ordering of imports
-
-// We order imports by translating to our own representation and then sorting.
-// The Rust AST data structures are really bad for this. Rustfmt applies a bunch
-// of normalisations to imports and since we want to sort based on the result
-// of these (and to maintain idempotence) we must apply the same normalisations
-// to the data structures for sorting.
-//
-// We sort `self` and `super` before other imports, then identifier imports,
-// then glob imports, then lists of imports. We do not take aliases into account
-// when ordering unless the imports are identical except for the alias (rare in
-// practice).
-
-// FIXME(#2531) - we should unify the comparison code here with the formatting
-// code elsewhere since we are essentially string-ifying twice. Furthermore, by
-// parsing to our own format on comparison, we repeat a lot of work when
-// sorting.
-
-// FIXME we do a lot of allocation to make our own representation.
-#[derive(Debug, Clone, Eq, PartialEq)]
-enum UseSegment {
- Ident(String, Option<String>),
- Slf(Option<String>),
- Super(Option<String>),
- Glob,
- List(Vec<UseTree>),
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-struct UseTree {
- path: Vec<UseSegment>,
-}
-
-impl UseSegment {
- // Clone a version of self with any top-level alias removed.
- fn remove_alias(&self) -> UseSegment {
- match *self {
- UseSegment::Ident(ref s, _) => UseSegment::Ident(s.clone(), None),
- UseSegment::Slf(_) => UseSegment::Slf(None),
- UseSegment::Super(_) => UseSegment::Super(None),
- _ => self.clone(),
- }
- }
-}
-
-impl UseTree {
- fn from_ast(a: &ast::UseTree) -> UseTree {
- let mut result = UseTree { path: vec![] };
- for p in &a.prefix.segments {
- result.path.push(UseSegment::Ident(
- (*p.identifier.name.as_str()).to_owned(),
- None,
- ));
- }
- match a.kind {
- UseTreeKind::Glob => {
- result.path.push(UseSegment::Glob);
- }
- UseTreeKind::Nested(ref list) => {
- result.path.push(UseSegment::List(
- list.iter().map(|t| Self::from_ast(&t.0)).collect(),
- ));
- }
- UseTreeKind::Simple(ref rename) => {
- let mut name = (*path_to_imported_ident(&a.prefix).name.as_str()).to_owned();
- let alias = if &name == &*rename.name.as_str() {
- None
- } else {
- Some((&*rename.name.as_str()).to_owned())
- };
-
- let segment = if &name == "self" {
- UseSegment::Slf(alias)
- } else if &name == "super" {
- UseSegment::Super(alias)
- } else {
- UseSegment::Ident(name, alias)
- };
-
- // `name` is already in result.
- result.path.pop();
- result.path.push(segment);
- }
- }
- result
- }
-
- // Do the adjustments that rustfmt does elsewhere to use paths.
- fn normalize(mut self) -> UseTree {
- let mut last = self.path.pop().expect("Empty use tree?");
- // Hack around borrow checker.
- let mut normalize_sole_list = false;
- let mut aliased_self = false;
-
- // Normalise foo::self -> foo.
- if let UseSegment::Slf(None) = last {
- return self;
- }
-
- // Normalise foo::self as bar -> foo as bar.
- if let UseSegment::Slf(_) = last {
- match self.path.last() {
- None => {}
- Some(UseSegment::Ident(_, None)) => {
- aliased_self = true;
- }
- _ => unreachable!(),
- }
- }
-
- if aliased_self {
- match self.path.last() {
- Some(UseSegment::Ident(_, ref mut old_rename)) => {
- assert!(old_rename.is_none());
- if let UseSegment::Slf(Some(rename)) = last {
- *old_rename = Some(rename);
- return self;
- }
- }
- _ => unreachable!(),
- }
- }
-
- // Normalise foo::{bar} -> foo::bar
- if let UseSegment::List(ref list) = last {
- if list.len() == 1 && list[0].path.len() == 1 {
- normalize_sole_list = true;
- }
- }
-
- if normalize_sole_list {
- match last {
- UseSegment::List(list) => {
- self.path.push(list[0].path[0].clone());
- return self.normalize();
- }
- _ => unreachable!(),
- }
- }
-
- // Recursively normalize elements of a list use (including sorting the list).
- if let UseSegment::List(list) = last {
- let mut list: Vec<_> = list.into_iter().map(|ut| ut.normalize()).collect();
- list.sort();
- last = UseSegment::List(list);
- }
-
- self.path.push(last);
- self
- }
-}
-
-impl PartialOrd for UseSegment {
- fn partial_cmp(&self, other: &UseSegment) -> Option<Ordering> {
- Some(self.cmp(other))
- }
-}
-impl PartialOrd for UseTree {
- fn partial_cmp(&self, other: &UseTree) -> Option<Ordering> {
- Some(self.cmp(other))
- }
-}
-impl Ord for UseSegment {
- fn cmp(&self, other: &UseSegment) -> Ordering {
- use self::UseSegment::*;
-
- match (self, other) {
- (&Slf(ref a), &Slf(ref b)) | (&Super(ref a), &Super(ref b)) => a.cmp(b),
- (&Glob, &Glob) => Ordering::Equal,
- (&Ident(ref ia, ref aa), &Ident(ref ib, ref ab)) => {
- let ident_ord = ia.cmp(ib);
- if ident_ord != Ordering::Equal {
- return ident_ord;
- }
- if aa.is_none() && ab.is_some() {
- return Ordering::Less;
- }
- if aa.is_some() && ab.is_none() {
- return Ordering::Greater;
- }
- aa.cmp(ab)
- }
- (&List(ref a), &List(ref b)) => {
- for (a, b) in a.iter().zip(b.iter()) {
- let ord = a.cmp(b);
- if ord != Ordering::Equal {
- return ord;
- }
- }
-
- a.len().cmp(&b.len())
- }
- (&Slf(_), _) => Ordering::Less,
- (_, &Slf(_)) => Ordering::Greater,
- (&Super(_), _) => Ordering::Less,
- (_, &Super(_)) => Ordering::Greater,
- (&Ident(..), _) => Ordering::Less,
- (_, &Ident(..)) => Ordering::Greater,
- (&Glob, _) => Ordering::Less,
- (_, &Glob) => Ordering::Greater,
- }
- }
-}
-impl Ord for UseTree {
- fn cmp(&self, other: &UseTree) -> Ordering {
- for (a, b) in self.path.iter().zip(other.path.iter()) {
- let ord = a.cmp(b);
- // The comparison without aliases is a hack to avoid situations like
- // comparing `a::b` to `a as c` - where the latter should be ordered
- // first since it is shorter.
- if ord != Ordering::Equal && a.remove_alias().cmp(&b.remove_alias()) != Ordering::Equal
- {
- return ord;
- }
- }
-
- self.path.len().cmp(&other.path.len())
- }
-}
-
-#[cfg(test)]
-mod test {
- use super::*;
-
- // Parse the path part of an import. This parser is not robust and is only
- // suitable for use in a test harness.
- fn parse_use_tree(s: &str) -> UseTree {
- use std::iter::Peekable;
- use std::mem::swap;
- use std::str::Chars;
-
- struct Parser<'a> {
- input: Peekable<Chars<'a>>,
- }
-
- impl<'a> Parser<'a> {
- fn bump(&mut self) {
- self.input.next().unwrap();
- }
- fn eat(&mut self, c: char) {
- assert!(self.input.next().unwrap() == c);
- }
- fn push_segment(
- result: &mut Vec<UseSegment>,
- buf: &mut String,
- alias_buf: &mut Option<String>,
- ) {
- if !buf.is_empty() {
- let mut alias = None;
- swap(alias_buf, &mut alias);
- if buf == "self" {
- result.push(UseSegment::Slf(alias));
- *buf = String::new();
- *alias_buf = None;
- } else if buf == "super" {
- result.push(UseSegment::Super(alias));
- *buf = String::new();
- *alias_buf = None;
- } else {
- let mut name = String::new();
- swap(buf, &mut name);
- result.push(UseSegment::Ident(name, alias));
- }
- }
- }
- fn parse_in_list(&mut self) -> UseTree {
- let mut result = vec![];
- let mut buf = String::new();
- let mut alias_buf = None;
- while let Some(&c) = self.input.peek() {
- match c {
- '{' => {
- assert!(buf.is_empty());
- self.bump();
- result.push(UseSegment::List(self.parse_list()));
- self.eat('}');
- }
- '*' => {
- assert!(buf.is_empty());
- self.bump();
- result.push(UseSegment::Glob);
- }
- ':' => {
- self.bump();
- self.eat(':');
- Self::push_segment(&mut result, &mut buf, &mut alias_buf);
- }
- '}' | ',' => {
- Self::push_segment(&mut result, &mut buf, &mut alias_buf);
- return UseTree { path: result };
- }
- ' ' => {
- self.bump();
- self.eat('a');
- self.eat('s');
- self.eat(' ');
- alias_buf = Some(String::new());
- }
- c => {
- self.bump();
- if let Some(ref mut buf) = alias_buf {
- buf.push(c);
- } else {
- buf.push(c);
- }
- }
- }
- }
- Self::push_segment(&mut result, &mut buf, &mut alias_buf);
- UseTree { path: result }
- }
-
- fn parse_list(&mut self) -> Vec<UseTree> {
- let mut result = vec![];
- loop {
- match self.input.peek().unwrap() {
- ',' | ' ' => self.bump(),
- '}' => {
- return result;
- }
- _ => result.push(self.parse_in_list()),
- }
- }
- }
- }
-
- let mut parser = Parser {
- input: s.chars().peekable(),
- };
- parser.parse_in_list()
- }
-
- #[test]
- fn test_use_tree_normalize() {
- assert_eq!(parse_use_tree("a::self").normalize(), parse_use_tree("a"));
- assert_eq!(
- parse_use_tree("a::self as foo").normalize(),
- parse_use_tree("a as foo")
- );
- assert_eq!(parse_use_tree("a::{self}").normalize(), parse_use_tree("a"));
- assert_eq!(parse_use_tree("a::{b}").normalize(), parse_use_tree("a::b"));
- assert_eq!(
- parse_use_tree("a::{b, c::self}").normalize(),
- parse_use_tree("a::{b, c}")
- );
- assert_eq!(
- parse_use_tree("a::{b as bar, c::self}").normalize(),
- parse_use_tree("a::{b as bar, c}")
- );
- }
-
- #[test]
- fn test_use_tree_ord() {
- assert!(parse_use_tree("a").normalize() < parse_use_tree("aa").normalize());
- assert!(parse_use_tree("a").normalize() < parse_use_tree("a::a").normalize());
- assert!(parse_use_tree("a").normalize() < parse_use_tree("*").normalize());
- assert!(parse_use_tree("a").normalize() < parse_use_tree("{a, b}").normalize());
- assert!(parse_use_tree("*").normalize() < parse_use_tree("{a, b}").normalize());
-
- assert!(
- parse_use_tree("aaaaaaaaaaaaaaa::{bb, cc, dddddddd}").normalize()
- < parse_use_tree("aaaaaaaaaaaaaaa::{bb, cc, ddddddddd}").normalize()
- );
- assert!(
- parse_use_tree("serde::de::{Deserialize}").normalize()
- < parse_use_tree("serde_json").normalize()
- );
- assert!(parse_use_tree("a::b::c").normalize() < parse_use_tree("a::b::*").normalize());
- assert!(
- parse_use_tree("foo::{Bar, Baz}").normalize()
- < parse_use_tree("{Bar, Baz}").normalize()
- );
-
- assert!(
- parse_use_tree("foo::{self as bar}").normalize()
- < parse_use_tree("foo::{qux as bar}").normalize()
- );
- assert!(
- parse_use_tree("foo::{qux as bar}").normalize()
- < parse_use_tree("foo::{baz, qux as bar}").normalize()
- );
- assert!(
- parse_use_tree("foo::{self as bar, baz}").normalize()
- < parse_use_tree("foo::{baz, qux as bar}").normalize()
- );
-
- assert!(parse_use_tree("Foo").normalize() < parse_use_tree("foo").normalize());
- assert!(parse_use_tree("foo").normalize() < parse_use_tree("foo::Bar").normalize());
-
- assert!(
- parse_use_tree("std::cmp::{d, c, b, a}").normalize()
- < parse_use_tree("std::cmp::{b, e, g, f}").normalize()
- );
- }
-}