1 // A generic trait to abstract the rewriting of an element (of the AST).
3 use std::cell::RefCell;
5 use syntax::parse::ParseSess;
7 use syntax::source_map::{SourceMap, Span};
9 use crate::config::{Config, IndentStyle};
10 use crate::shape::Shape;
11 use crate::skip::SkipContext;
12 use crate::visitor::SnippetProvider;
13 use crate::FormatReport;
15 pub(crate) trait Rewrite {
16 /// Rewrite self into shape.
17 fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String>;
20 impl<T: Rewrite> Rewrite for ptr::P<T> {
21 fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
22 (**self).rewrite(context, shape)
27 pub(crate) struct RewriteContext<'a> {
28 pub(crate) parse_session: &'a ParseSess,
29 pub(crate) source_map: &'a SourceMap,
30 pub(crate) config: &'a Config,
31 pub(crate) inside_macro: RefCell<bool>,
32 // Force block indent style even if we are using visual indent style.
33 pub(crate) use_block: RefCell<bool>,
34 // When `is_if_else_block` is true, unindent the comment on top
35 // of the `else` or `else if`.
36 pub(crate) is_if_else_block: RefCell<bool>,
37 // When rewriting chain, veto going multi line except the last element
38 pub(crate) force_one_line_chain: RefCell<bool>,
39 pub(crate) snippet_provider: &'a SnippetProvider<'a>,
40 // Used for `format_snippet`
41 pub(crate) macro_rewrite_failure: RefCell<bool>,
42 pub(crate) report: FormatReport,
43 pub(crate) skip_context: SkipContext,
46 impl<'a> RewriteContext<'a> {
47 pub(crate) fn snippet(&self, span: Span) -> &str {
48 self.snippet_provider.span_to_snippet(span).unwrap()
51 /// Returns `true` if we should use block indent style for rewriting function call.
52 pub(crate) fn use_block_indent(&self) -> bool {
53 self.config.indent_style() == IndentStyle::Block || *self.use_block.borrow()
56 pub(crate) fn budget(&self, used_width: usize) -> usize {
57 self.config.max_width().saturating_sub(used_width)
60 pub(crate) fn inside_macro(&self) -> bool {
61 *self.inside_macro.borrow()
64 pub(crate) fn is_if_else_block(&self) -> bool {
65 *self.is_if_else_block.borrow()