bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Format assignment

Browse source
This commit is contained in:
Marcus Klaas 2015-08-21 13:31:09 +02:00
parent ca39467cde
commit 120fd2426e
16 changed files with 284 additions and 76 deletions
Download patch file Download diff file Expand all files Collapse all files

134
src/expr.rs
View file

@ -106,6 +106,12 @@ impl Rewrite for ast::Expr {
ast::Expr_::ExprPath(ref qself, ref path) => {
rewrite_path(context, qself.as_ref(), path, width, offset)
}
ast::Expr_::ExprAssign(ref lhs, ref rhs) => {
rewrite_assignment(context, lhs, rhs, None, width, offset)
}
ast::Expr_::ExprAssignOp(ref op, ref lhs, ref rhs) => {
rewrite_assignment(context, lhs, rhs, Some(op), width, offset)
}
// FIXME #184 Note that this formatting is broken due to a bad span
// from the parser.
// `continue`
@ -116,10 +122,47 @@ impl Rewrite for ast::Expr {
};
Some(format!("continue{}", id_str))
}
ast::Expr_::ExprBreak(ref opt_ident) => {
let id_str = match *opt_ident {
Some(ident) => format!(" {}", ident),
None => String::new(),
};
Some(format!("break{}", id_str))
}
ast::Expr_::ExprClosure(capture, ref fn_decl, ref body) => {
rewrite_closure(capture, fn_decl, body, self.span, context, width, offset)
}
_ => context.codemap.span_to_snippet(self.span).ok(),
_ => {
// We do not format these expressions yet, but they should still
// satisfy our width restrictions.
let snippet = context.codemap.span_to_snippet(self.span).unwrap();
{
let mut lines = snippet.lines();
// The caller of this function has already placed `offset`
// characters on the first line.
let first_line_max_len = try_opt!(context.config.max_width.checked_sub(offset));
if lines.next().unwrap().len() > first_line_max_len {
return None;
}
// The other lines must fit within the maximum width.
if lines.find(|line| line.len() > context.config.max_width).is_some() {
return None;
}
// `width` is the maximum length of the last line, excluding
// indentation.
// A special check for the last line, since the caller may
// place trailing characters on this line.
if snippet.lines().rev().next().unwrap().len() > offset + width {
return None;
}
}
Some(snippet)
}
}
}
}
@ -402,7 +445,7 @@ fn rewrite_match(context: &RewriteContext,
width: usize,
offset: usize)
-> Option<String> {
if arms.len() == 0 {
if arms.is_empty() {
return None;
}
@ -440,7 +483,7 @@ fn rewrite_match(context: &RewriteContext,
result.push('\n');
}
let missed_str = missed_str.trim();
if missed_str.len() > 0 {
if !missed_str.is_empty() {
result.push('\n');
result.push_str(&arm_indent_str);
result.push_str(missed_str);
@ -473,7 +516,7 @@ fn rewrite_match(context: &RewriteContext,
fn arm_start_pos(arm: &ast::Arm) -> BytePos {
let &ast::Arm { ref attrs, ref pats, .. } = arm;
if attrs.len() > 0 {
if !attrs.is_empty() {
return attrs[0].span.lo
}
@ -492,7 +535,7 @@ impl Rewrite for ast::Arm {
// FIXME this is all a bit grotty, would be nice to abstract out the
// treatment of attributes.
let attr_str = if attrs.len() > 0 {
let attr_str = if !attrs.is_empty() {
// We only use this visitor for the attributes, should we use it for
// more?
let mut attr_visitor = FmtVisitor::from_codemap(context.codemap, context.config);
@ -539,7 +582,7 @@ impl Rewrite for ast::Arm {
let mut pats_str = String::new();
for p in pat_strs {
if pats_str.len() > 0 {
if !pats_str.is_empty() {
if vertical {
pats_str.push_str(" |\n");
pats_str.push_str(&indent_str);
@ -584,7 +627,7 @@ impl Rewrite for ast::Arm {
}
// We have to push the body to the next line.
if comma.len() == 0 {
if comma.is_empty() {
// We're trying to fit a block in, but it still failed, give up.
return None;
}
@ -645,6 +688,8 @@ fn rewrite_pat_expr(context: &RewriteContext,
pat: Option<&ast::Pat>,
expr: &ast::Expr,
matcher: &str,
// Connecting piece between pattern and expression,
// *without* trailing space.
connector: &str,
width: usize,
offset: usize)
@ -665,18 +710,18 @@ fn rewrite_pat_expr(context: &RewriteContext,
// The expression may (partionally) fit on the current line.
if width > extra_offset + 1 {
let mut corrected_offset = extra_offset;
if pat.is_some() {
result.push(' ');
corrected_offset += 1;
}
let spacer = if pat.is_some() {
" "
} else {
""
};
let expr_rewrite = expr.rewrite(context,
width - corrected_offset,
offset + corrected_offset);
width - extra_offset - spacer.len(),
offset + extra_offset + spacer.len());
if let Some(expr_string) = expr_rewrite {
result.push_str(spacer);
result.push_str(&expr_string);
return Some(result);
}
@ -810,7 +855,7 @@ fn rewrite_struct_lit<'a>(context: &RewriteContext,
let path_str = try_opt!(path.rewrite(context, width - 2, offset));
// Foo { a: Foo } - indent is +3, width is -5.
let h_budget = width.checked_sub(path_str.len() + 5).unwrap_or(0);
let h_budget = try_opt!(width.checked_sub(path_str.len() + 5));
let (indent, v_budget) = match context.config.struct_lit_style {
StructLitStyle::VisualIndent => {
(offset + path_str.len() + 3, h_budget)
@ -1008,7 +1053,62 @@ fn rewrite_unary_op(context: &RewriteContext,
ast::UnOp::UnNeg => "-",
};
let subexpr = try_opt!(expr.rewrite(context, try_opt!(width.checked_sub(operator_str.len())), offset));
let subexpr =
try_opt!(expr.rewrite(context, try_opt!(width.checked_sub(operator_str.len())), offset));
Some(format!("{}{}", operator_str, subexpr))
}
fn rewrite_assignment(context: &RewriteContext,
lhs: &ast::Expr,
rhs: &ast::Expr,
op: Option<&ast::BinOp>,
width: usize,
offset: usize)
-> Option<String> {
let operator_str = match op {
Some(op) => context.codemap.span_to_snippet(op.span).unwrap(),
None => "=".to_owned(),
};
// 1 = space between lhs and operator.
let max_width = try_opt!(width.checked_sub(operator_str.len() + 1));
let lhs_str = format!("{} {}", try_opt!(lhs.rewrite(context, max_width, offset)), operator_str);
rewrite_assign_rhs(&context, lhs_str, rhs, width, offset)
}
// The left hand side must contain everything up to, and including, the
// assignment operator.
pub fn rewrite_assign_rhs<S: Into<String>>(context: &RewriteContext,
lhs: S,
ex: &ast::Expr,
width: usize,
offset: usize)
-> Option<String> {
let mut result = lhs.into();
// 1 = space between operator and rhs.
let max_width = try_opt!(width.checked_sub(result.len() + 1));
let rhs = ex.rewrite(&context, max_width, offset + result.len() + 1);
match rhs {
Some(new_str) => {
result.push(' ');
result.push_str(&new_str)
}
None => {
// Expression did not fit on the same line as the identifier. Retry
// on the next line.
let new_offset = offset + context.config.tab_spaces;
result.push_str(&format!("\n{}", make_indent(new_offset)));
let max_width = try_opt!(context.config.max_width.checked_sub(new_offset + 1));
let rhs = try_opt!(ex.rewrite(&context, max_width, new_offset));
result.push_str(&rhs);
}
}
Some(result)
}