1 files changed, 103 insertions, 0 deletions
diff --git a/third_party/rust/bindgen/regex_set.rs b/third_party/rust/bindgen/regex_set.rs
new file mode 100644
index 0000000000..6246dd255b
--- /dev/null
+++ b/third_party/rust/bindgen/regex_set.rs
@@ -0,0 +1,103 @@
+//! A type that represents the union of a set of regular expressions.
+
+use regex::RegexSet as RxSet;
+use std::cell::Cell;
+
+/// A dynamic set of regular expressions.
+#[derive(Clone, Debug, Default)]
+pub struct RegexSet {
+    items: Vec<String>,
+    /// Whether any of the items in the set was ever matched. The length of this
+    /// vector is exactly the length of `items`.
+    matched: Vec<Cell<bool>>,
+    set: Option<RxSet>,
+    /// Whether we should record matching items in the `matched` vector or not.
+    record_matches: bool,
+}
+
+impl RegexSet {
+    /// Create a new RegexSet
+    pub fn new() -> RegexSet {
+        RegexSet {
+            ..Default::default()
+        }
+    }
+
+    /// Is this set empty?
+    pub fn is_empty(&self) -> bool {
+        self.items.is_empty()
+    }
+
+    /// Insert a new regex into this set.
+    pub fn insert<S>(&mut self, string: S)
+    where
+        S: AsRef<str>,
+    {
+        let string = string.as_ref().to_owned();
+        if string == "*" {
+            warn!("using wildcard patterns (`*`) is no longer considered valid. Use `.*` instead");
+        }
+        self.items.push(string);
+        self.matched.push(Cell::new(false));
+        self.set = None;
+    }
+
+    /// Returns slice of String from its field 'items'
+    pub fn get_items(&self) -> &[String] {
+        &self.items[..]
+    }
+
+    /// Returns an iterator over regexes in the set which didn't match any
+    /// strings yet.
+    pub fn unmatched_items(&self) -> impl Iterator<Item = &String> {
+        self.items.iter().enumerate().filter_map(move |(i, item)| {
+            if !self.record_matches || self.matched[i].get() {
+                return None;
+            }
+
+            Some(item)
+        })
+    }
+
+    /// Construct a RegexSet from the set of entries we've accumulated.
+    ///
+    /// Must be called before calling `matches()`, or it will always return
+    /// false.
+    pub fn build(&mut self, record_matches: bool) {
+        let items = self.items.iter().map(|item| format!("^({})$", item));
+        self.record_matches = record_matches;
+        self.set = match RxSet::new(items) {
+            Ok(x) => Some(x),
+            Err(e) => {
+                warn!("Invalid regex in {:?}: {:?}", self.items, e);
+                None
+            }
+        }
+    }
+
+    /// Does the given `string` match any of the regexes in this set?
+    pub fn matches<S>(&self, string: S) -> bool
+    where
+        S: AsRef<str>,
+    {
+        let s = string.as_ref();
+        let set = match self.set {
+            Some(ref set) => set,
+            None => return false,
+        };
+
+        if !self.record_matches {
+            return set.is_match(s);
+        }
+
+        let matches = set.matches(s);
+        if !matches.matched_any() {
+            return false;
+        }
+        for i in matches.iter() {
+            self.matched[i].set(true);
+        }
+
+        true
+    }
+}