perf: decode_mappings

Author: SyMind

src/helpers.rs

@@ -111,9 +111,9 @@ pub struct GeneratedInfo {
   pub generated_column: u32,
 }
 
-pub fn decode_mappings<'b, 'a: 'b>(
+pub fn decode_mappings<'a>(
   source_map: &'a SourceMap,
-) -> impl Iterator<Item = Mapping> + 'b {
+) -> impl Iterator<Item = Mapping> + 'a {
   SegmentIter::new(source_map.mappings())
 }
 
@@ -640,7 +640,7 @@ fn stream_chunks_of_source_map_final<'a>(
     }
   };
   for mapping in source_map.decoded_mappings() {
-    on_mapping(mapping);
+    on_mapping(&mapping);
   }
   result
 }
@@ -672,11 +672,11 @@ fn stream_chunks_of_source_map_full<'a>(
   let mut tracking_generated_column: u32 = 0;
   let mut tracking_mapping_original: Option<OriginalLocation> = None;
 
-  let mut mappings_iter = source_map.decoded_mappings().iter();
+  let mut mappings_iter = source_map.decoded_mappings();
   let mut current_mapping = mappings_iter.next();
 
   for (current_generated_index, c) in source.char_indices() {
-    if let Some(mapping) = current_mapping {
+    if let Some(mapping) = &current_mapping {
       if mapping.generated_line == current_generated_line
         && mapping.generated_column == current_generated_column
       {
@@ -794,7 +794,7 @@ fn stream_chunks_of_source_map_lines_final<'a>(
     }
   };
   for mapping in source_map.decoded_mappings() {
-    on_mapping(mapping);
+    on_mapping(&mapping);
   }
   result
 }
@@ -864,7 +864,7 @@ fn stream_chunks_of_source_map_lines_full<'a>(
     }
   };
   for mapping in source_map.decoded_mappings() {
-    on_mapping(mapping);
+    on_mapping(&mapping);
   }
   while current_generated_line as usize <= lines.len() {
     let chunk = lines[current_generated_line as usize - 1];

src/source.rs

@@ -4,7 +4,7 @@ use std::{
   convert::{TryFrom, TryInto},
   fmt,
   hash::{Hash, Hasher},
-  sync::{Arc, OnceLock},
+  sync::Arc,
 };
 
 use dyn_clone::DynClone;
@@ -194,7 +194,6 @@ pub struct SourceMap {
   sources_content: Vec<Cow<'static, str>>,
   names: Vec<Cow<'static, str>>,
   source_root: Option<String>,
-  decoded_mappings: OnceLock<Vec<Mapping>>,
 }
 
 impl Hash for SourceMap {
@@ -224,7 +223,6 @@ impl SourceMap {
       sources_content,
       names,
       source_root: None,
-      decoded_mappings: Default::default(),
     }
   }
 
@@ -239,10 +237,8 @@ impl SourceMap {
   }
 
   /// Get the decoded mappings in [SourceMap].
-  pub fn decoded_mappings(&'_ self) -> &[Mapping] {
-    self
-      .decoded_mappings
-      .get_or_init(|| decode_mappings(self).collect::<Vec<_>>())
+  pub fn decoded_mappings<'a>(&'a self) -> impl Iterator<Item = Mapping> + 'a {
+    decode_mappings(self)
   }
 
   /// Get the mappings string in [SourceMap].
@@ -433,7 +429,6 @@ impl TryFrom<RawSourceMap> for SourceMap {
       sources_content,
       names,
       source_root: raw.source_root,
-      decoded_mappings: Default::default(),
     })
   }
 }