OpenE2K/rust
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

StripUnconfigured::in_cfg: simplify with slice patterns

Browse Source
This commit is contained in:
Mazdak Farrokhzad 2019-12-31 07:15:43 +01:00
parent 2e6eaceede
commit 4f17dce4dc
1 changed files with 16 additions and 36 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

52
src/librustc_parse/config.rs
View File

@ -347,7 +347,13 @@ impl<'a> StripUnconfigured<'a> {
if !is_cfg(attr) {
return true;
}
let meta_item = match validate_attr::parse_meta(self.sess, attr) {
Ok(meta_item) => meta_item,
Err(mut err) => {
err.emit();
return true;
}
};
let error = |span, msg, suggestion: &str| {
let mut err = self.sess.span_diagnostic.struct_span_err(span, msg);
if !suggestion.is_empty() {
@ -361,41 +367,15 @@ impl<'a> StripUnconfigured<'a> {
err.emit();
true
};
let meta_item = match validate_attr::parse_meta(self.sess, attr) {
Ok(meta_item) => meta_item,
Err(mut err) => {
err.emit();
return true;
}
};
let nested_meta_items = if let Some(nested_meta_items) = meta_item.meta_item_list() {
nested_meta_items
} else {
return error(
meta_item.span,
"`cfg` is not followed by parentheses",
"cfg(/* predicate */)",
);
};
if nested_meta_items.is_empty() {
return error(meta_item.span, "`cfg` predicate is not specified", "");
} else if nested_meta_items.len() > 1 {
return error(
nested_meta_items.last().unwrap().span(),
"multiple `cfg` predicates are specified",
"",
);
}
match nested_meta_items[0].meta_item() {
Some(meta_item) => attr::cfg_matches(meta_item, self.sess, self.features),
None => error(
nested_meta_items[0].span(),
"`cfg` predicate key cannot be a literal",
"",
),
let span = meta_item.span;
match meta_item.meta_item_list() {
None => error(span, "`cfg` is not followed by parentheses", "cfg(/* predicate */)"),
Some([]) => error(span, "`cfg` predicate is not specified", ""),
Some([_, .., l]) => error(l.span(), "multiple `cfg` predicates are specified", ""),
Some([single]) => match single.meta_item() {
Some(meta_item) => attr::cfg_matches(meta_item, self.sess, self.features),
None => error(single.span(), "`cfg` predicate key cannot be a literal", ""),
},
}
})
}