user0/rust
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

chains: fix visual indent chain layout

Browse source
This commit is contained in:
Nick Cameron 2018-07-12 10:44:06 +12:00
parent 8618a55834
commit f9510a55eb
2 changed files with 85 additions and 61 deletions
Download patch file Download diff file Expand all files Collapse all files

140
src/chains.rs
View file

@ -275,12 +275,12 @@ impl Rewrite for Chain {
};
formatter.format_root(&self.parent, context, shape)?;
if let result @ Some(_) = formatter.pure_root() {
return result;
if let Some(result) = formatter.pure_root() {
return wrap_str(result, context.config.max_width(), shape);
}
// Decide how to layout the rest of the chain.
let child_shape = formatter.child_shape(context, shape);
let child_shape = formatter.child_shape(context, shape)?;
formatter.format_children(context, child_shape)?;
formatter.format_last_child(context, shape, child_shape)?;
@ -309,7 +309,7 @@ trait ChainFormatter {
context: &RewriteContext,
shape: Shape,
) -> Option<()>;
fn child_shape(&self, context: &RewriteContext, shape: Shape) -> Shape;
fn child_shape(&self, context: &RewriteContext, shape: Shape) -> Option<Shape>;
fn format_children(&mut self, context: &RewriteContext, child_shape: Shape) -> Option<()>;
fn format_last_child(
&mut self,
@ -414,8 +414,10 @@ impl<'a> ChainFormatterShared<'a> {
let all_in_one_line =
self.rewrites.iter().all(|s| !s.contains('\n')) && one_line_budget > 0;
let last_shape = if all_in_one_line || extendable {
let last_shape = if all_in_one_line {
shape.sub_width(last.tries)?
} else if extendable {
child_shape.sub_width(last.tries)?
} else {
child_shape.sub_width(shape.rhs_overhead(context.config) + last.tries)?
};
@ -481,7 +483,7 @@ impl<'a> ChainFormatterShared<'a> {
if *context.force_one_line_chain.borrow() {
return None;
}
child_shape.indent.to_string_with_newline(context.config)
child_shape.to_string_with_newline(context.config)
};
let mut rewrite_iter = self.rewrites.iter();
@ -512,37 +514,6 @@ impl<'a> ChainFormatterBlock<'a> {
is_block_like: Vec::with_capacity(chain.children.len() + 1),
}
}
// States whether an expression's last line exclusively consists of closing
// parens, braces, and brackets in its idiomatic formatting.
fn is_block_expr(context: &RewriteContext, expr: &ast::Expr, repr: &str) -> bool {
match expr.node {
ast::ExprKind::Mac(..)
| ast::ExprKind::Call(..)
| ast::ExprKind::MethodCall(..)
| ast::ExprKind::Struct(..)
| ast::ExprKind::While(..)
| ast::ExprKind::WhileLet(..)
| ast::ExprKind::If(..)
| ast::ExprKind::IfLet(..)
| ast::ExprKind::Block(..)
| ast::ExprKind::Loop(..)
| ast::ExprKind::ForLoop(..)
| ast::ExprKind::Match(..) => repr.contains('\n'),
ast::ExprKind::Paren(ref expr)
| ast::ExprKind::Binary(_, _, ref expr)
| ast::ExprKind::Index(_, ref expr)
| ast::ExprKind::Unary(_, ref expr)
| ast::ExprKind::Closure(_, _, _, _, ref expr, _)
| ast::ExprKind::Try(ref expr)
| ast::ExprKind::Yield(Some(ref expr)) => Self::is_block_expr(context, expr, repr),
// This can only be a string lit
ast::ExprKind::Lit(_) => {
repr.contains('\n') && trimmed_last_line_width(repr) <= context.config.tab_spaces()
}
_ => false,
}
}
}
impl<'a> ChainFormatter for ChainFormatterBlock<'a> {
@ -554,7 +525,7 @@ impl<'a> ChainFormatter for ChainFormatterBlock<'a> {
) -> Option<()> {
let mut root_rewrite: String = parent.rewrite(context, shape)?;
let mut root_ends_with_block = Self::is_block_expr(context, &parent.expr, &root_rewrite);
let mut root_ends_with_block = is_block_expr(context, &parent.expr, &root_rewrite);
let tab_width = context.config.tab_spaces().saturating_sub(shape.offset);
while root_rewrite.len() <= tab_width && !root_rewrite.contains('\n') {
@ -565,7 +536,7 @@ impl<'a> ChainFormatter for ChainFormatterBlock<'a> {
None => break,
}
root_ends_with_block = Self::is_block_expr(context, &item.expr, &root_rewrite);
root_ends_with_block = is_block_expr(context, &item.expr, &root_rewrite);
self.shared.children = &self.shared.children[..self.shared.children.len() - 1];
if self.shared.children.is_empty() {
@ -577,19 +548,21 @@ impl<'a> ChainFormatter for ChainFormatterBlock<'a> {
Some(())
}
fn child_shape(&self, context: &RewriteContext, shape: Shape) -> Shape {
if self.is_block_like[0] {
shape
} else {
shape.block_indent(context.config.tab_spaces())
}.with_max_width(context.config)
fn child_shape(&self, context: &RewriteContext, shape: Shape) -> Option<Shape> {
Some(
if self.is_block_like[0] {
shape.block_indent(0)
} else {
shape.block_indent(context.config.tab_spaces())
}.with_max_width(context.config),
)
}
fn format_children(&mut self, context: &RewriteContext, child_shape: Shape) -> Option<()> {
for item in self.shared.children[1..].iter().rev() {
let rewrite = item.rewrite_postfix(context, child_shape)?;
self.is_block_like
.push(Self::is_block_expr(context, &item.expr, &rewrite));
.push(is_block_expr(context, &item.expr, &rewrite));
self.shared.rewrites.push(rewrite);
}
Some(())
@ -618,12 +591,15 @@ impl<'a> ChainFormatter for ChainFormatterBlock<'a> {
// Format a chain using visual indent.
struct ChainFormatterVisual<'a> {
shared: ChainFormatterShared<'a>,
// The extra offset from the chain's shape to the position of the `.`
offset: usize,
}
impl<'a> ChainFormatterVisual<'a> {
fn new(chain: &'a Chain) -> ChainFormatterVisual<'a> {
ChainFormatterVisual {
shared: ChainFormatterShared::new(chain),
offset: 0,
}
}
}
@ -635,23 +611,31 @@ impl<'a> ChainFormatter for ChainFormatterVisual<'a> {
context: &RewriteContext,
shape: Shape,
) -> Option<()> {
// Determines if we can continue formatting a given expression on the same line.
fn is_continuable(expr: &ast::Expr) -> bool {
match expr.node {
ast::ExprKind::Path(..) => true,
_ => false,
}
}
let parent_shape = shape.visual_indent(0);
let mut root_rewrite = parent.rewrite(context, parent_shape)?;
let multiline = root_rewrite.contains('\n');
self.offset = if multiline {
last_line_width(&root_rewrite).saturating_sub(shape.used_width())
} else {
trimmed_last_line_width(&root_rewrite)
};
if !root_rewrite.contains('\n') && is_continuable(&parent.expr) {
if !multiline || is_block_expr(context, &parent.expr, &root_rewrite) {
let item = &self.shared.children[self.shared.children.len() - 1];
let overhead = last_line_width(&root_rewrite);
let shape = parent_shape.offset_left(overhead)?;
let rewrite = item.rewrite_postfix(context, shape)?;
root_rewrite.push_str(&rewrite);
let child_shape = parent_shape
.visual_indent(self.offset)
.sub_width(self.offset)?;
let rewrite = item.rewrite_postfix(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_postfix(context, parent_shape)?;
root_rewrite.push_str(&rewrite);
self.offset = 0;
}
}
self.shared.children = &self.shared.children[..self.shared.children.len() - 1];
}
@ -660,8 +644,11 @@ impl<'a> ChainFormatter for ChainFormatterVisual<'a> {
Some(())
}
fn child_shape(&self, context: &RewriteContext, shape: Shape) -> Shape {
shape.visual_indent(0).with_max_width(context.config)
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))
}
fn format_children(&mut self, context: &RewriteContext, child_shape: Shape) -> Option<()> {
@ -691,3 +678,34 @@ impl<'a> ChainFormatter for ChainFormatterVisual<'a> {
self.shared.pure_root()
}
}
// States whether an expression's last line exclusively consists of closing
// parens, braces, and brackets in its idiomatic formatting.
fn is_block_expr(context: &RewriteContext, expr: &ast::Expr, repr: &str) -> bool {
match expr.node {
ast::ExprKind::Mac(..)
| ast::ExprKind::Call(..)
| ast::ExprKind::MethodCall(..)
| ast::ExprKind::Struct(..)
| ast::ExprKind::While(..)
| ast::ExprKind::WhileLet(..)
| ast::ExprKind::If(..)
| ast::ExprKind::IfLet(..)
| ast::ExprKind::Block(..)
| ast::ExprKind::Loop(..)
| ast::ExprKind::ForLoop(..)
| ast::ExprKind::Match(..) => repr.contains('\n'),
ast::ExprKind::Paren(ref expr)
| ast::ExprKind::Binary(_, _, ref expr)
| ast::ExprKind::Index(_, ref expr)
| ast::ExprKind::Unary(_, ref expr)
| ast::ExprKind::Closure(_, _, _, _, ref expr, _)
| ast::ExprKind::Try(ref expr)
| ast::ExprKind::Yield(Some(ref expr)) => is_block_expr(context, expr, repr),
// This can only be a string lit
ast::ExprKind::Lit(_) => {
repr.contains('\n') && trimmed_last_line_width(repr) <= context.config.tab_spaces()
}
_ => false,
}
}

6
src/shape.rs
View file

@ -274,6 +274,12 @@ impl Shape {
);
Shape { width, ..*self }
}
pub fn to_string_with_newline(&self, config: &Config) -> Cow<'static, str> {
let mut offset_indent = self.indent;
offset_indent.alignment = self.offset;
offset_indent.to_string_inner(config, 0)
}
}
#[cfg(test)]