Add Arbitrary to Glob

Derive `Arbitrary` for `Glob` struct. This feature is optional so the
derive will only take place when the feature is enabled. This feature is
mandatory when using Glob in fuzz testing.

Signed-off-by: William Johnson <wjohnson@whamcloud.com>

crates/globset/Cargo.toml

@@ -21,6 +21,7 @@ bench = false
 
 [dependencies]
 aho-corasick = "1.1.1"
+arbitrary = { version = "1.3.2", optional = true, features = ["derive"] }
 bstr = { version = "1.6.2", default-features = false, features = ["std"] }
 log = { version = "0.4.20", optional = true }
 serde = { version = "1.0.188", optional = true }

crates/globset/src/glob.rs

@@ -71,6 +71,7 @@ impl MatchStrategy {
 /// It cannot be used directly to match file paths, but it can be converted
 /// to a regular expression string or a matcher.
 #[derive(Clone, Debug, Eq)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 pub struct Glob {
     glob: String,
     re: String,
@@ -193,6 +194,7 @@ pub struct GlobBuilder<'a> {
 }
 
 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 struct GlobOptions {
     /// Whether to match case insensitively.
     case_insensitive: bool,
@@ -219,6 +221,7 @@ impl GlobOptions {
 }
 
 #[derive(Clone, Debug, Default, Eq, PartialEq)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 struct Tokens(Vec<Token>);
 
 impl std::ops::Deref for Tokens {
@@ -235,6 +238,7 @@ impl std::ops::DerefMut for Tokens {
 }
 
 #[derive(Clone, Debug, Eq, PartialEq)]
+#[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
 enum Token {
     Literal(char),
     Any,