use expr::{rewrite_unary_prefix, rewrite_pair, rewrite_tuple};
use types::rewrite_path;
-use syntax::ast::{BindingMode, Pat, Pat_};
+use syntax::ast::{BindingMode, Pat, Pat_, FieldPat};
-// FIXME(#18): implement pattern formatting.
impl Rewrite for Pat {
fn rewrite(&self, context: &RewriteContext, width: usize, offset: Indent) -> Option<String> {
match self.node {
Pat_::PatBox(ref pat) => rewrite_unary_prefix(context, "box ", &**pat, width, offset),
- Pat_::PatIdent(binding_mode, ident, None) => {
+ Pat_::PatIdent(binding_mode, ident, ref sub_pat) => {
let (prefix, mutability) = match binding_mode {
BindingMode::BindByRef(mutability) => ("ref ", mutability),
BindingMode::BindByValue(mutability) => ("", mutability),
};
let mut_infix = format_mutability(mutability);
- let result = format!("{}{}{}", prefix, mut_infix, ident.node);
+ let id_str = ident.node.to_string();
+
+ let sub_pat = match *sub_pat {
+ Some(ref p) => {
+ let width = try_opt!(width.checked_sub(prefix.len() + mut_infix.len() +
+ id_str.len()));
+ format!(" @ {}", try_opt!(p.rewrite(context, width, offset)))
+ }
+ None => "".to_owned(),
+ };
+
+ let result = format!("{}{}{}{}", prefix, mut_infix, id_str, sub_pat);
wrap_str(result, context.config.max_width, width, offset)
}
Pat_::PatWild => {
width,
offset)
}
- Pat_::PatEnum(ref path, Some(ref pat_vec)) => {
- let path_str = try_opt!(::types::rewrite_path(context,
- true,
- None,
- path,
- width,
- offset));
+ Pat_::PatEnum(ref path, ref pat_vec) => {
+ let path_str = try_opt!(rewrite_path(context, true, None, path, width, offset));
- if pat_vec.is_empty() {
- Some(path_str)
- } else {
- // 1 = (
- let width = try_opt!(width.checked_sub(path_str.len() + 1));
- let offset = offset + path_str.len() + 1;
- let items = itemize_list(context.codemap,
- pat_vec.iter(),
- ")",
- |item| item.span.lo,
- |item| item.span.hi,
- |item| item.rewrite(context, width, offset),
- span_after(self.span, "(", context.codemap),
- self.span.hi);
- Some(format!("{}({})",
- path_str,
- try_opt!(format_item_list(items, width, offset, context.config))))
+ match *pat_vec {
+ Some(ref pat_vec) => {
+ if pat_vec.is_empty() {
+ Some(path_str)
+ } else {
+ // 1 = (
+ let width = try_opt!(width.checked_sub(path_str.len() + 1));
+ let offset = offset + path_str.len() + 1;
+ let items = itemize_list(context.codemap,
+ pat_vec.iter(),
+ ")",
+ |item| item.span.lo,
+ |item| item.span.hi,
+ |item| item.rewrite(context, width, offset),
+ span_after(self.span, "(", context.codemap),
+ self.span.hi);
+ Some(format!("{}({})",
+ path_str,
+ try_opt!(format_item_list(items,
+ width,
+ offset,
+ context.config))))
+ }
+ }
+ None => Some(format!("{}(..)", path_str)),
}
}
Pat_::PatLit(ref expr) => expr.rewrite(context, width, offset),
- // FIXME(#8): format remaining pattern variants.
- Pat_::PatIdent(_, _, Some(..)) |
- Pat_::PatEnum(_, None) |
- Pat_::PatStruct(..) |
- Pat_::PatVec(..) |
+ Pat_::PatVec(ref prefix, ref slice_pat, ref suffix) => {
+ // Rewrite all the sub-patterns.
+ let prefix = prefix.iter().map(|p| p.rewrite(context, width, offset));
+ let slice_pat = slice_pat.as_ref().map(|p| {
+ Some(format!("{}..", try_opt!(p.rewrite(context, width, offset))))
+ });
+ let suffix = suffix.iter().map(|p| p.rewrite(context, width, offset));
+
+ // Munge them together.
+ let pats = prefix.chain(slice_pat.into_iter()).chain(suffix);
+
+ // Check that all the rewrites succeeded, and if not return None.
+ let (somes, nones) = pats.partition::<Vec<Option<String>>, _>(Option::is_some);
+ if nones.len() > 0 {
+ return None;
+ }
+
+ // Unwrap all the sub-strings and join them with commas.
+ let pats = somes.into_iter().map(|p| p.unwrap()).collect::<Vec<_>>().join(", ");
+ Some(format!("[{}]", pats))
+ }
+ Pat_::PatStruct(ref path, ref fields, elipses) => {
+ let path = try_opt!(rewrite_path(context, true, None, path, width, offset));
+
+ let (elipses_str, terminator) = if elipses {
+ (", ..", "..")
+ } else {
+ ("", "}")
+ };
+
+ let budget = try_opt!(width.checked_sub(path.len() + 5 + elipses_str.len()));
+ // FIXME Using visual indenting, should use block or visual to match
+ // struct lit preference (however, in practice I think it is rare
+ // for struct patterns to be multi-line).
+ let offset = offset + path.len() + 3;
+
+ let items = itemize_list(context.codemap,
+ fields.iter(),
+ terminator,
+ |f| f.span.lo,
+ |f| f.span.hi,
+ |f| f.node.rewrite(context, budget, offset),
+ span_after(self.span, "{", context.codemap),
+ self.span.hi);
+ let mut field_string = try_opt!(format_item_list(items,
+ budget,
+ offset,
+ context.config));
+ if elipses {
+ if field_string.contains('\n') {
+ field_string.push_str(",\n");
+ field_string.push_str(&offset.to_string(context.config));
+ field_string.push_str("..");
+ } else {
+ if field_string.len() > 0 {
+ field_string.push_str(", ");
+ }
+ field_string.push_str("..");
+ }
+ }
+
+ if field_string.len() == 0 {
+ Some(format!("{} {{}}", path))
+ } else {
+ Some(format!("{} {{ {} }}", path, field_string))
+ }
+ }
+ // FIXME(#819) format pattern macros.
Pat_::PatMac(..) => {
wrap_str(context.snippet(self.span),
context.config.max_width,
}
}
}
+
+impl Rewrite for FieldPat {
+ fn rewrite(&self, context: &RewriteContext, width: usize, offset: Indent) -> Option<String> {
+ let pat = self.pat.rewrite(context, width, offset);
+ if self.is_shorthand {
+ pat
+ } else {
+ Some(format!("{}: {}", self.ident.to_string(), try_opt!(pat)))
+ }
+ }
+}