1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 // A generic trait to abstract the rewriting of an element (of the AST).
13 use syntax::codemap::{CodeMap, Span};
14 use syntax::parse::ParseSess;
16 use config::{Config, IndentStyle};
18 use visitor::SnippetProvider;
20 use std::cell::RefCell;
23 /// Rewrite self into shape.
24 fn rewrite(&self, context: &RewriteContext, shape: Shape) -> Option<String>;
28 pub struct RewriteContext<'a> {
29 pub parse_session: &'a ParseSess,
30 pub codemap: &'a CodeMap,
31 pub config: &'a Config,
32 pub inside_macro: RefCell<bool>,
33 // Force block indent style even if we are using visual indent style.
34 pub use_block: RefCell<bool>,
35 // When `format_if_else_cond_comment` is true, unindent the comment on top
36 // of the `else` or `else if`.
37 pub is_if_else_block: RefCell<bool>,
38 // When rewriting chain, veto going multi line except the last element
39 pub force_one_line_chain: RefCell<bool>,
40 pub snippet_provider: &'a SnippetProvider<'a>,
43 impl<'a> RewriteContext<'a> {
44 pub fn snippet(&self, span: Span) -> &str {
45 self.snippet_provider.span_to_snippet(span).unwrap()
48 /// Return true if we should use block indent style for rewriting function call.
49 pub fn use_block_indent(&self) -> bool {
50 self.config.indent_style() == IndentStyle::Block || *self.use_block.borrow()
53 pub fn budget(&self, used_width: usize) -> usize {
54 self.config.max_width().checked_sub(used_width).unwrap_or(0)
57 pub fn inside_macro(&self) -> bool {
58 *self.inside_macro.borrow()
61 pub fn is_if_else_block(&self) -> bool {
62 *self.is_if_else_block.borrow()