Mutex::new() is now const

Cargo.lock

@@ -3356,7 +3356,6 @@ name = "roc_builtins"
 version = "0.0.1"
 dependencies = [
  "dunce",
- "lazy_static",
  "roc_collections",
  "roc_module",
  "roc_region",
@@ -3826,7 +3825,6 @@ name = "roc_module"
 version = "0.0.1"
 dependencies = [
  "bumpalo",
- "lazy_static",
  "roc_collections",
  "roc_error_macros",
  "roc_ident",
@@ -4815,7 +4813,6 @@ dependencies = [
  "bumpalo",
  "indoc",
  "insta",
- "lazy_static",
  "pretty_assertions",
  "roc_builtins",
  "roc_can",

crates/compiler/builtins/Cargo.toml

@@ -12,7 +12,6 @@ roc_region = { path = "../region" }
 roc_module = { path = "../module" }
 roc_target = { path = "../roc_target" }
 roc_utils = { path = "../../utils" }
-lazy_static = "1.4.0"
 
 [build-dependencies]
 # dunce can be removed once ziglang/zig#5109 is fixed

crates/compiler/collections/src/small_string_interner.rs

@@ -69,6 +69,14 @@ impl std::fmt::Debug for SmallStringInterner {
 }
 
 impl SmallStringInterner {
+    pub const fn new() -> Self {
+        Self {
+            buffer: Vec::new(),
+            lengths: Vec::new(),
+            offsets: Vec::new(),
+        }
+    }
+
     pub fn with_capacity(capacity: usize) -> Self {
         Self {
             // guess: the average symbol length is 5

crates/compiler/collections/src/vec_map.rs

@@ -6,14 +6,18 @@ pub struct VecMap<K, V> {
 
 impl<K, V> Default for VecMap<K, V> {
     fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl<K, V> VecMap<K, V> {
+    pub const fn new() -> Self {
         Self {
             keys: Vec::new(),
             values: Vec::new(),
         }
     }
-}
 
-impl<K, V> VecMap<K, V> {
     pub fn len(&self) -> usize {
         debug_assert_eq!(self.keys.len(), self.values.len());
         self.keys.len()

crates/compiler/module/Cargo.toml

@@ -12,7 +12,6 @@ roc_ident = { path = "../ident" }
 roc_collections = { path = "../collections" }
 roc_error_macros = {path = "../../error_macros"}
 bumpalo = { version = "3.11.0", features = ["collections"] }
-lazy_static = "1.4.0"
 static_assertions = "1.1.0"
 snafu = { version = "0.7.1", features = ["backtraces"] }
 

crates/compiler/module/src/lib.rs

@@ -9,6 +9,3 @@ pub mod ident;
 pub mod low_level;
 pub mod module_err;
 pub mod symbol;
-
-#[macro_use]
-extern crate lazy_static;

crates/compiler/module/src/symbol.rs

@@ -246,29 +246,13 @@ fn fallback_debug_fmt(symbol: Symbol, f: &mut fmt::Formatter) -> fmt::Result {
     write!(f, "`{:?}.{:?}`", module_id, ident_id)
 }
 
-// TODO this is only here to prevent clippy from complaining about an unused
+/// This is used in Debug builds only, to let us have a Debug instance
-// #[macro_use] on lazy_statc in --release builds, because as of January 2020,
+/// which displays not only the Module ID, but also the Module Name which
-// we only use lazy_static in the debug configuration. If we ever start using
+/// corresponds to that ID.
-// lazy_static in release builds, this do-nothing macro invocation will be safe to delete!
+///
-//
-// There's probably also a way to get clippy to stop complaining about the unused
-// #[macro_use] but it didn't seem worth the effort since probably someday we'll
-// end up using it in release builds anyway. Right? ...Right?
-lazy_static! {}
-
 #[cfg(any(debug_assertions, feature = "debug-symbols"))]
-lazy_static! {
+static DEBUG_MODULE_ID_NAMES: std::sync::Mutex<roc_collections::SmallStringInterner> =
-    /// This is used in Debug builds only, to let us have a Debug instance
+    std::sync::Mutex::new(roc_collections::SmallStringInterner::new());
-    /// which displays not only the Module ID, but also the Module Name which
-    /// corresponds to that ID.
-    ///
-    static ref DEBUG_MODULE_ID_NAMES: std::sync::Mutex<roc_collections::SmallStringInterner> =
-        // This stores a u32 key instead of a ModuleId key so that if there's
-        // a problem with ModuleId's Debug implementation, logging this for diagnostic
-        // purposes won't recursively trigger ModuleId's Debug instance in the course of printing
-        // this out.
-        std::sync::Mutex::new(roc_collections::SmallStringInterner::with_capacity(10));
-}
 
 #[derive(Debug, Default, Clone)]
 pub struct Interns {
@@ -338,18 +322,16 @@ pub fn get_module_ident_ids_mut<'a>(
         })
 }
 
+/// This is used in Debug builds only, to let us have a Debug instance
+/// which displays not only the Module ID, but also the Module Name which
+/// corresponds to that ID.
 #[cfg(any(debug_assertions, feature = "debug-symbols"))]
-lazy_static! {
+static DEBUG_IDENT_IDS_BY_MODULE_ID: std::sync::Mutex<roc_collections::VecMap<u32, IdentIds>> =
-    /// This is used in Debug builds only, to let us have a Debug instance
-    /// which displays not only the Module ID, but also the Module Name which
-    /// corresponds to that ID.
-    static ref DEBUG_IDENT_IDS_BY_MODULE_ID: std::sync::Mutex<roc_collections::VecMap<u32, IdentIds>> =
     // This stores a u32 key instead of a ModuleId key so that if there's
     // a problem with ModuleId's Debug implementation, logging this for diagnostic
     // purposes won't recursively trigger ModuleId's Debug instance in the course of printing
     // this out.
-        std::sync::Mutex::new(roc_collections::VecMap::default());
+    std::sync::Mutex::new(roc_collections::VecMap::new());
-}
 
 /// A globally unique ID that gets assigned to each module as it is loaded.
 #[derive(Copy, Clone, PartialEq, Eq, Hash)]

crates/compiler/test_derive/Cargo.toml

@@ -26,7 +26,6 @@ roc_region = { path = "../region" }
 roc_solve = { path = "../solve" }
 roc_debug_flags = { path = "../debug_flags" }
 bumpalo = { version = "3.11.0", features = ["collections"] }
-lazy_static = "1.4.0"
 indoc = "1.0.7"
 ven_pretty = { path = "../../vendor/pretty" }
 pretty_assertions = "1.3.0"

crates/repl_test/src/wasm.rs

@@ -23,9 +23,10 @@ thread_local! {
 // Even if Cargo uses many threads, these tests won't go any faster. But that's fine, they're quick.
 lazy_static! {
     static ref COMPILER: Instance = init_compiler();
-    static ref TEST_MUTEX: Mutex<()> = Mutex::new(());
 }
 
+static TEST_MUTEX: Mutex<()> = Mutex::new(());
+
 /// Load the compiler .wasm file and get it ready to execute
 /// THIS FUNCTION TAKES 4 SECONDS TO RUN
 fn init_compiler() -> Instance {