use std::iter::repeat;
-use config::lists::*;
use syntax::source_map::{BytePos, Span};
use syntax::{ast, ptr};
-use comment::{combine_strs_with_missing_comments, rewrite_comment};
-use config::{Config, ControlBraceStyle, IndentStyle};
-use expr::{
- format_expr, is_empty_block, is_simple_block, is_unsafe_block, prefer_next_line,
+use crate::comment::{combine_strs_with_missing_comments, rewrite_comment};
+use crate::config::lists::*;
+use crate::config::{Config, ControlBraceStyle, IndentStyle, Version};
+use crate::expr::{
+ format_expr, is_empty_block, is_simple_block, is_unsafe_block, prefer_next_line, rewrite_cond,
rewrite_multiple_patterns, ExprType, RhsTactics,
};
-use lists::{itemize_list, write_list, ListFormatting};
-use rewrite::{Rewrite, RewriteContext};
-use shape::Shape;
-use source_map::SpanUtils;
-use spanned::Spanned;
-use utils::{
+use crate::lists::{itemize_list, write_list, ListFormatting};
+use crate::rewrite::{Rewrite, RewriteContext};
+use crate::shape::Shape;
+use crate::source_map::SpanUtils;
+use crate::spanned::Spanned;
+use crate::utils::{
contains_skip, extra_offset, first_line_width, inner_attributes, last_line_extendable, mk_sp,
- ptr_vec_to_ref_vec, trimmed_last_line_width,
+ ptr_vec_to_ref_vec, semicolon_for_expr, trimmed_last_line_width,
};
/// A simple wrapper type against `ast::Arm`. Used inside `write_list()`.
}
impl<'a> Rewrite for ArmWrapper<'a> {
- fn rewrite(&self, context: &RewriteContext, shape: Shape) -> Option<String> {
+ fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
rewrite_match_arm(context, self.arm, shape, self.is_last)
}
}
pub fn rewrite_match(
- context: &RewriteContext,
+ context: &RewriteContext<'_>,
cond: &ast::Expr,
arms: &[ast::Arm],
shape: Shape,
/// Collect a byte position of the beginning `|` for each arm, if available.
fn collect_beginning_verts(
- context: &RewriteContext,
+ context: &RewriteContext<'_>,
arms: &[ast::Arm],
span: Span,
) -> Vec<Option<BytePos>> {
}
fn rewrite_match_arms(
- context: &RewriteContext,
+ context: &RewriteContext<'_>,
arms: &[ast::Arm],
shape: Shape,
span: Span,
}
fn rewrite_match_arm(
- context: &RewriteContext,
+ context: &RewriteContext<'_>,
arm: &ast::Arm,
shape: Shape,
is_last: bool,
) -> Option<String> {
let (missing_span, attrs_str) = if !arm.attrs.is_empty() {
if contains_skip(&arm.attrs) {
- let (_, body) = flatten_arm_body(context, &arm.body);
+ let (_, body) = flatten_arm_body(context, &arm.body, None);
// `arm.span()` does not include trailing comma, add it manually.
return Some(format!(
"{}{}",
} else {
(mk_sp(arm.span().lo(), arm.span().lo()), String::new())
};
- let pats_str =
- rewrite_match_pattern(context, &ptr_vec_to_ref_vec(&arm.pats), &arm.guard, shape)
- .and_then(|pats_str| {
- combine_strs_with_missing_comments(
- context,
- &attrs_str,
- &pats_str,
- missing_span,
- shape,
- false,
- )
- })?;
- let arrow_span = mk_sp(arm.pats.last().unwrap().span.hi(), arm.body.span.lo());
- rewrite_match_body(
- context,
- &arm.body,
- &pats_str,
- shape,
- arm.guard.is_some(),
- arrow_span,
- is_last,
- )
-}
-
-fn rewrite_match_pattern(
- context: &RewriteContext,
- pats: &[&ast::Pat],
- guard: &Option<ast::Guard>,
- shape: Shape,
-) -> Option<String> {
// Patterns
// 5 = ` => {`
let pat_shape = shape.sub_width(5)?;
- let pats_str = rewrite_multiple_patterns(context, pats, pat_shape)?;
+ let pats_str = rewrite_multiple_patterns(context, &ptr_vec_to_ref_vec(&arm.pats), pat_shape)?;
// Guard
+ let block_like_pat = trimmed_last_line_width(&pats_str) <= context.config.tab_spaces();
+ let new_line_guard = pats_str.contains('\n') && !block_like_pat;
let guard_str = rewrite_guard(
context,
- guard,
+ &arm.guard,
shape,
trimmed_last_line_width(&pats_str),
- pats_str.contains('\n'),
+ new_line_guard,
)?;
- Some(format!("{}{}", pats_str, guard_str))
+ let lhs_str = combine_strs_with_missing_comments(
+ context,
+ &attrs_str,
+ &format!("{}{}", pats_str, guard_str),
+ missing_span,
+ shape,
+ false,
+ )?;
+
+ let arrow_span = mk_sp(arm.pats.last().unwrap().span.hi(), arm.body.span.lo());
+ rewrite_match_body(
+ context,
+ &arm.body,
+ &lhs_str,
+ shape,
+ guard_str.contains('\n'),
+ arrow_span,
+ is_last,
+ )
}
fn block_can_be_flattened<'a>(
- context: &RewriteContext,
+ context: &RewriteContext<'_>,
expr: &'a ast::Expr,
) -> Option<&'a ast::Block> {
match expr.node {
// (extend, body)
// @extend: true if the arm body can be put next to `=>`
// @body: flattened body, if the body is block with a single expression
-fn flatten_arm_body<'a>(context: &'a RewriteContext, body: &'a ast::Expr) -> (bool, &'a ast::Expr) {
+fn flatten_arm_body<'a>(
+ context: &'a RewriteContext<'_>,
+ body: &'a ast::Expr,
+ opt_shape: Option<Shape>,
+) -> (bool, &'a ast::Expr) {
let can_extend =
|expr| !context.config.force_multiline_blocks() && can_flatten_block_around_this(expr);
if let Some(ref block) = block_can_be_flattened(context, body) {
if let ast::StmtKind::Expr(ref expr) = block.stmts[0].node {
if let ast::ExprKind::Block(..) = expr.node {
- flatten_arm_body(context, expr)
+ flatten_arm_body(context, expr, None)
} else {
- (can_extend(expr), &*expr)
+ let cond_becomes_muti_line = opt_shape
+ .and_then(|shape| rewrite_cond(context, expr, shape))
+ .map_or(false, |cond| cond.contains('\n'));
+ if cond_becomes_muti_line {
+ (false, &*body)
+ } else {
+ (can_extend(expr), &*expr)
+ }
}
} else {
(false, &*body)
}
fn rewrite_match_body(
- context: &RewriteContext,
+ context: &RewriteContext<'_>,
body: &ptr::P<ast::Expr>,
pats_str: &str,
shape: Shape,
arrow_span: Span,
is_last: bool,
) -> Option<String> {
- let (extend, body) = flatten_arm_body(context, body);
+ let (extend, body) = flatten_arm_body(
+ context,
+ body,
+ shape.offset_left(extra_offset(pats_str, shape) + 4),
+ );
let (is_block, is_empty_block) = if let ast::ExprKind::Block(ref block, _) = body.node {
(
true,
// Look for comments between `=>` and the start of the body.
let arrow_comment = {
let arrow_snippet = context.snippet(arrow_span).trim();
- let arrow_index = arrow_snippet.find("=>").unwrap();
+ // search for the arrow starting from the end of the snippet since there may be a match
+ // expression within the guard
+ let arrow_index = arrow_snippet.rfind("=>").unwrap();
// 2 = `=>`
let comment_str = arrow_snippet[arrow_index + 2..].trim();
if comment_str.is_empty() {
} else {
""
};
- ("{", format!("{}}}{}", indent_str, comma))
+ let semicolon = if context.config.version() == Version::One {
+ ""
+ } else {
+ if semicolon_for_expr(context, body) {
+ ";"
+ } else {
+ ""
+ }
+ };
+ ("{", format!("{}{}}}{}", semicolon, indent_str, comma))
} else {
("", String::from(","))
};
}
impl Rewrite for ast::Guard {
- fn rewrite(&self, context: &RewriteContext, shape: Shape) -> Option<String> {
+ fn rewrite(&self, context: &RewriteContext<'_>, shape: Shape) -> Option<String> {
match self {
ast::Guard::If(ref expr) => expr.rewrite(context, shape),
}
// The `if ...` guard on a match arm.
fn rewrite_guard(
- context: &RewriteContext,
+ context: &RewriteContext<'_>,
guard: &Option<ast::Guard>,
shape: Shape,
// The amount of space used up on this line for the pattern in
&& budget >= 2
&& (block_str[1..].find(|c: char| !c.is_whitespace()).unwrap() == block_str.len() - 2)
{
- "{}".to_owned()
+ String::from("{}")
} else {
- block_str.to_owned()
+ block_str
}
})
}
projects / rust.git / blobdiff