Implement glob ignores (#272)

* Add Glob wrapper type with better serialization

* Introduce PathIgnoreRule struct

* Implement equality for Glob type

* Add PathIgnoreRule to InstanceContext

* Implement glob ignores in directory middleware

* Fix up filters

* Use Iterator::all instead of loop

* Add project-level configuration for glob ignores

* Add test project for glob ignores

* Wire up project file and snapshots to make glob ignores work

* Better codepaths for adding ignore rules with empty iterators

* Add test for globs inherited from parent projects

* Add test details, support glob ignores in nested projects

* Add feature flag for globs

* Switch to use ExactSizeIterator instead of size_hint

* Remove glob visitor

src/glob.rs

@@ -0,0 +1,50 @@
+//! Wrapper around globset's Glob type that has better serialization
+//! characteristics by coupling Glob and GlobMatcher into a single type.
+
+use std::path::Path;
+
+use globset::{Glob as InnerGlob, GlobMatcher};
+use serde::{de::Error as _, Deserialize, Deserializer, Serialize, Serializer};
+
+pub use globset::Error;
+
+#[derive(Debug, Clone)]
+pub struct Glob {
+    inner: InnerGlob,
+    matcher: GlobMatcher,
+}
+
+impl Glob {
+    pub fn new(glob: &str) -> Result<Self, Error> {
+        let inner = InnerGlob::new(glob)?;
+        let matcher = inner.compile_matcher();
+
+        Ok(Glob { inner, matcher })
+    }
+
+    pub fn is_match<P: AsRef<Path>>(&self, path: P) -> bool {
+        self.matcher.is_match(path)
+    }
+}
+
+impl PartialEq for Glob {
+    fn eq(&self, other: &Self) -> bool {
+        self.inner == other.inner
+    }
+}
+
+impl Eq for Glob {}
+
+impl Serialize for Glob {
+    fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
+        serializer.serialize_str(self.inner.glob())
+    }
+}
+
+impl<'de> Deserialize<'de> for Glob {
+    fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
+        let glob = <&str as Deserialize>::deserialize(deserializer)?;
+
+        Glob::new(glob).map_err(D::Error::custom)
+    }
+}