diff options
Diffstat (limited to 'src/tools/rustfmt/src/chains.rs')
-rw-r--r-- | src/tools/rustfmt/src/chains.rs | 124 |
1 files changed, 90 insertions, 34 deletions
diff --git a/src/tools/rustfmt/src/chains.rs b/src/tools/rustfmt/src/chains.rs index a1a73cf4b..cbe523c6c 100644 --- a/src/tools/rustfmt/src/chains.rs +++ b/src/tools/rustfmt/src/chains.rs @@ -70,10 +70,66 @@ use crate::rewrite::{Rewrite, RewriteContext}; use crate::shape::Shape; use crate::source_map::SpanUtils; use crate::utils::{ - self, first_line_width, last_line_extendable, last_line_width, mk_sp, rewrite_ident, - trimmed_last_line_width, wrap_str, + self, filtered_str_fits, first_line_width, last_line_extendable, last_line_width, mk_sp, + rewrite_ident, trimmed_last_line_width, wrap_str, }; +use thin_vec::ThinVec; + +/// Provides the original input contents from the span +/// of a chain element with trailing spaces trimmed. +fn format_overflow_style(span: Span, context: &RewriteContext<'_>) -> Option<String> { + context.snippet_provider.span_to_snippet(span).map(|s| { + s.lines() + .map(|l| l.trim_end()) + .collect::<Vec<_>>() + .join("\n") + }) +} + +fn format_chain_item( + item: &ChainItem, + context: &RewriteContext<'_>, + rewrite_shape: Shape, + allow_overflow: bool, +) -> Option<String> { + if allow_overflow { + item.rewrite(context, rewrite_shape) + .or_else(|| format_overflow_style(item.span, context)) + } else { + item.rewrite(context, rewrite_shape) + } +} + +fn get_block_child_shape( + prev_ends_with_block: bool, + context: &RewriteContext<'_>, + shape: Shape, +) -> Shape { + if prev_ends_with_block { + shape.block_indent(0) + } else { + shape.block_indent(context.config.tab_spaces()) + } + .with_max_width(context.config) +} + +fn get_visual_style_child_shape( + context: &RewriteContext<'_>, + shape: Shape, + offset: usize, + parent_overflowing: bool, +) -> Option<Shape> { + if !parent_overflowing { + shape + .with_max_width(context.config) + .offset_left(offset) + .map(|s| s.visual_indent(0)) + } else { + Some(shape.visual_indent(offset)) + } +} + pub(crate) fn rewrite_chain( expr: &ast::Expr, context: &RewriteContext<'_>, @@ -114,7 +170,7 @@ enum ChainItemKind { MethodCall( ast::PathSegment, Vec<ast::GenericArg>, - Vec<ptr::P<ast::Expr>>, + ThinVec<ptr::P<ast::Expr>>, ), StructField(symbol::Ident), TupleField(symbol::Ident, bool), @@ -496,6 +552,8 @@ struct ChainFormatterShared<'a> { // The number of children in the chain. This is not equal to `self.children.len()` // because `self.children` will change size as we process the chain. child_count: usize, + // Whether elements are allowed to overflow past the max_width limit + allow_overflow: bool, } impl<'a> ChainFormatterShared<'a> { @@ -505,6 +563,8 @@ impl<'a> ChainFormatterShared<'a> { rewrites: Vec::with_capacity(chain.children.len() + 1), fits_single_line: false, child_count: chain.children.len(), + // TODO(calebcartwright) + allow_overflow: false, } } @@ -517,6 +577,14 @@ impl<'a> ChainFormatterShared<'a> { } } + fn format_children(&mut self, context: &RewriteContext<'_>, child_shape: Shape) -> Option<()> { + for item in &self.children[..self.children.len() - 1] { + let rewrite = format_chain_item(item, context, child_shape, self.allow_overflow)?; + self.rewrites.push(rewrite); + } + Some(()) + } + // Rewrite the last child. The last child of a chain requires special treatment. We need to // know whether 'overflowing' the last child make a better formatting: // @@ -729,22 +797,12 @@ impl<'a> ChainFormatter for ChainFormatterBlock<'a> { } fn child_shape(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<Shape> { - Some( - if self.root_ends_with_block { - shape.block_indent(0) - } else { - shape.block_indent(context.config.tab_spaces()) - } - .with_max_width(context.config), - ) + let block_end = self.root_ends_with_block; + Some(get_block_child_shape(block_end, context, shape)) } fn format_children(&mut self, context: &RewriteContext<'_>, child_shape: Shape) -> Option<()> { - for item in &self.shared.children[..self.shared.children.len() - 1] { - let rewrite = item.rewrite(context, child_shape)?; - self.shared.rewrites.push(rewrite); - } - Some(()) + self.shared.format_children(context, child_shape) } fn format_last_child( @@ -808,15 +866,14 @@ impl<'a> ChainFormatter for ChainFormatterVisual<'a> { .visual_indent(self.offset) .sub_width(self.offset)?; let rewrite = item.rewrite(context, child_shape)?; - match wrap_str(rewrite, context.config.max_width(), shape) { - Some(rewrite) => root_rewrite.push_str(&rewrite), - None => { - // We couldn't fit in at the visual indent, try the last - // indent. - let rewrite = item.rewrite(context, parent_shape)?; - root_rewrite.push_str(&rewrite); - self.offset = 0; - } + if filtered_str_fits(&rewrite, context.config.max_width(), shape) { + root_rewrite.push_str(&rewrite); + } else { + // We couldn't fit in at the visual indent, try the last + // indent. + let rewrite = item.rewrite(context, parent_shape)?; + root_rewrite.push_str(&rewrite); + self.offset = 0; } self.shared.children = &self.shared.children[1..]; @@ -827,18 +884,17 @@ impl<'a> ChainFormatter for ChainFormatterVisual<'a> { } fn child_shape(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<Shape> { - shape - .with_max_width(context.config) - .offset_left(self.offset) - .map(|s| s.visual_indent(0)) + get_visual_style_child_shape( + context, + shape, + self.offset, + // TODO(calebcartwright): self.shared.permissibly_overflowing_parent, + false, + ) } fn format_children(&mut self, context: &RewriteContext<'_>, child_shape: Shape) -> Option<()> { - for item in &self.shared.children[..self.shared.children.len() - 1] { - let rewrite = item.rewrite(context, child_shape)?; - self.shared.rewrites.push(rewrite); - } - Some(()) + self.shared.format_children(context, child_shape) } fn format_last_child( |