Merge pull request trishume#391 from rhysd/issue-334

Fix crash on lazy initialization

Cargo.toml

@@ -24,7 +24,6 @@ fancy-regex = { version = "0.7", optional = true }
 walkdir = "2.0"
 regex-syntax = { version = "0.6", optional = true }
 lazy_static = "1.0"
-lazycell = "1.0"
 bitflags = "1.0.4"
 plist = { version = "1", optional = true }
 bincode = { version = "1.0", optional = true }
@@ -33,6 +32,7 @@ fnv = { version = "1.0", optional = true }
 serde = "1.0"
 serde_derive = "1.0"
 serde_json = "1.0"
+once_cell = "1.8"
 
 [dev-dependencies]
 criterion = { version = "0.3", features = [ "html_reports" ] }

src/parsing/regex.rs

@@ -1,4 +1,4 @@
-use lazycell::AtomicLazyCell;
+use once_cell::sync::OnceCell;
 use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use std::error::Error;
 
@@ -10,7 +10,7 @@ use std::error::Error;
 #[derive(Debug)]
 pub struct Regex {
     regex_str: String,
-    regex: AtomicLazyCell<regex_impl::Regex>,
+    regex: OnceCell<regex_impl::Regex>,
 }
 
 /// A region contains text positions for capture groups in a match result.
@@ -27,7 +27,7 @@ impl Regex {
     pub fn new(regex_str: String) -> Self {
         Self {
             regex_str,
-            regex: AtomicLazyCell::new(),
+            regex: OnceCell::new(),
         }
     }
 
@@ -65,22 +65,17 @@ impl Regex {
     }
 
     fn regex(&self) -> &regex_impl::Regex {
-        if let Some(regex) = self.regex.borrow() {
-            regex
-        } else {
-            let regex =
-                regex_impl::Regex::new(&self.regex_str).expect("regex string should be pre-tested");
-            self.regex.fill(regex).ok();
-            self.regex.borrow().unwrap()
-        }
+        self.regex.get_or_init(|| {
+            regex_impl::Regex::new(&self.regex_str).expect("regex string should be pre-tested")
+        })
     }
 }
 
 impl Clone for Regex {
     fn clone(&self) -> Self {
         Regex {
             regex_str: self.regex_str.clone(),
-            regex: AtomicLazyCell::new(),
+            regex: OnceCell::new(),
         }
     }
 }
@@ -275,9 +270,9 @@ mod tests {
     fn caches_compiled_regex() {
         let regex = Regex::new(String::from(r"\w+"));
 
-        assert!(!regex.regex.filled());
+        assert!(regex.regex.get().is_none());
         assert!(regex.is_match("test"));
-        assert!(regex.regex.filled());
+        assert!(regex.regex.get().is_some());
     }
 
     #[test]

src/parsing/syntax_set.rs

@@ -17,9 +17,9 @@ use std::io::{self, BufRead, BufReader};
 use std::fs::File;
 use std::mem;
 
-use lazycell::AtomicLazyCell;
 use super::regex::Regex;
 use crate::parsing::syntax_definition::ContextId;
+use once_cell::sync::OnceCell;
 
 /// A syntax set holds multiple syntaxes that have been linked together.
 ///
@@ -37,8 +37,8 @@ pub struct SyntaxSet {
     /// Stores the syntax index for every path that was loaded
     path_syntaxes: Vec<(String, usize)>,
 
-    #[serde(skip_serializing, skip_deserializing, default = "AtomicLazyCell::new")]
-    first_line_cache: AtomicLazyCell<FirstLineCache>,
+    #[serde(skip_serializing, skip_deserializing, default = "OnceCell::new")]
+    first_line_cache: OnceCell<FirstLineCache>,
     /// Metadata, e.g. indent and commenting information.
     ///
     /// NOTE: if serializing, you should handle metadata manually; that is, you should serialize and
@@ -110,7 +110,7 @@ impl Clone for SyntaxSet {
             contexts: self.contexts.clone(),
             path_syntaxes: self.path_syntaxes.clone(),
             // Will need to be re-initialized
-            first_line_cache: AtomicLazyCell::new(),
+            first_line_cache: OnceCell::new(),
             #[cfg(feature = "metadata")]
             metadata: self.metadata.clone(),
         }
@@ -123,14 +123,13 @@ impl Default for SyntaxSet {
             syntaxes: Vec::new(),
             contexts: Vec::new(),
             path_syntaxes: Vec::new(),
-            first_line_cache: AtomicLazyCell::new(),
+            first_line_cache: OnceCell::new(),
             #[cfg(feature = "metadata")]
             metadata: Metadata::default(),
         }
     }
 }
 
-
 impl SyntaxSet {
     pub fn new() -> SyntaxSet {
         SyntaxSet::default()
@@ -353,13 +352,8 @@ impl SyntaxSet {
     }
 
     fn first_line_cache(&self) -> &FirstLineCache {
-        if let Some(cache) = self.first_line_cache.borrow() {
-            cache
-        } else {
-            let cache = FirstLineCache::new(self.syntaxes());
-            self.first_line_cache.fill(cache).ok();
-            self.first_line_cache.borrow().unwrap()
-        }
+        self.first_line_cache
+            .get_or_init(|| FirstLineCache::new(self.syntaxes()))
     }
 
     pub fn find_unlinked_contexts(&self) -> BTreeSet<String> {
@@ -624,7 +618,7 @@ impl SyntaxSetBuilder {
             syntaxes,
             contexts: all_contexts,
             path_syntaxes,
-            first_line_cache: AtomicLazyCell::new(),
+            first_line_cache: OnceCell::new(),
             #[cfg(feature = "metadata")]
             metadata,
         }