refactor: Simplify SourceMapGetter and SourceMapper (#821)

Splitting out a simplification from
#819.

core/extension_set.rs

@@ -22,7 +22,6 @@ use crate::ModuleCodeString;
 use crate::OpDecl;
 use crate::OpMetricsFactoryFn;
 use crate::OpState;
-use crate::SourceMapGetter;
 
 /// Contribute to the `OpState` from each extension.
 pub fn setup_op_state(op_state: &mut OpState, extensions: &mut [Extension]) {
@@ -242,7 +241,7 @@ impl<'a> IntoIterator for &'a mut LoadedSources {
 fn load(
   transpiler: Option<&ExtensionTranspiler>,
   source: &ExtensionFileSource,
-  source_mapper: &mut SourceMapper<Rc<dyn SourceMapGetter>>,
+  source_mapper: &mut SourceMapper,
   load_callback: &mut impl FnMut(&ExtensionFileSource),
 ) -> Result<ModuleCodeString, AnyError> {
   load_callback(source);
@@ -263,7 +262,7 @@ fn load(
 pub fn into_sources(
   transpiler: Option<&ExtensionTranspiler>,
   extensions: &[Extension],
-  source_mapper: &mut SourceMapper<Rc<dyn SourceMapGetter>>,
+  source_mapper: &mut SourceMapper,
   mut load_callback: impl FnMut(&ExtensionFileSource),
 ) -> Result<LoadedSources, AnyError> {
   let mut sources = LoadedSources::default();

core/runtime/jsruntime.rs

@@ -407,7 +407,7 @@ pub type CompiledWasmModuleStore = CrossIsolateStore<v8::CompiledWasmModule>;
 /// Internal state for JsRuntime which is stored in one of v8::Isolate's
 /// embedder slots.
 pub struct JsRuntimeState {
-  pub(crate) source_mapper: RefCell<SourceMapper<Rc<dyn SourceMapGetter>>>,
+  pub(crate) source_mapper: RefCell<SourceMapper>,
   pub(crate) op_state: Rc<RefCell<OpState>>,
   pub(crate) shared_array_buffer_store: Option<SharedArrayBufferStore>,
   pub(crate) compiled_wasm_module_store: Option<CompiledWasmModuleStore>,
@@ -672,8 +672,7 @@ impl JsRuntime {
 
     // Load the sources and source maps
     let mut files_loaded = Vec::with_capacity(128);
-    let mut source_mapper: SourceMapper<Rc<dyn SourceMapGetter>> =
-      SourceMapper::new(options.source_map_getter);
+    let mut source_mapper = SourceMapper::new(options.source_map_getter);
     let mut sources = extension_set::into_sources(
       options.extension_transpiler.as_deref(),
       &extensions,

core/source_map.rs

@@ -19,23 +19,6 @@ pub trait SourceMapGetter {
   ) -> Option<String>;
 }
 
-impl<T> SourceMapGetter for Rc<T>
-where
-  T: SourceMapGetter + ?Sized,
-{
-  fn get_source_map(&self, file_name: &str) -> Option<Vec<u8>> {
-    (**self).get_source_map(file_name)
-  }
-
-  fn get_source_line(
-    &self,
-    file_name: &str,
-    line_number: usize,
-  ) -> Option<String> {
-    (**self).get_source_line(file_name, line_number)
-  }
-}
-
 pub enum SourceMapApplication {
   /// No mapping was applied, the location is unchanged.
   Unchanged,
@@ -54,18 +37,18 @@ pub enum SourceMapApplication {
 
 pub type SourceMapData = Cow<'static, [u8]>;
 
-pub struct SourceMapper<G: SourceMapGetter> {
+pub struct SourceMapper {
   maps: HashMap<String, Option<SourceMap>>,
   source_lines: HashMap<(String, i64), Option<String>>,
-  getter: Option<G>,
+  getter: Option<Rc<dyn SourceMapGetter>>,
   pub(crate) ext_source_maps: HashMap<String, SourceMapData>,
   // This is not the right place for this, but it's the easiest way to make
   // op_apply_source_map a fast op. This stashing should happen in #[op2].
   pub(crate) stashed_file_name: Option<String>,
 }
 
-impl<G: SourceMapGetter> SourceMapper<G> {
-  pub fn new(getter: Option<G>) -> Self {
+impl SourceMapper {
+  pub fn new(getter: Option<Rc<dyn SourceMapGetter>>) -> Self {
     Self {
       maps: Default::default(),
       source_lines: Default::default(),
@@ -75,7 +58,7 @@ impl<G: SourceMapGetter> SourceMapper<G> {
     }
   }
 
-  pub fn has_user_sources(&self) -> bool {
+  pub(crate) fn has_user_sources(&self) -> bool {
     self.getter.is_some()
   }