only add import references when they are used (#8874)

### Description

skips import to modules that are side effect free and have no exports
referenced

This allows to e. g. skip the `package` import completely in the
following code:

``` js
import { something } from "package"; // package is marked as side effect free

if (falsy) {
  something();
}
```

This could happen e. g. with code like `if(process.env.NODE_ENV ===
"production")`

### Testing Instructions

<!--
  Give a quick description of steps to test your changes.
-->

crates/turbopack-ecmascript/src/references/mod.rs

@@ -24,7 +24,7 @@ use std::{
  sync::Arc,
 };
 
-use anyhow::Result;
+use anyhow::{bail, Result};
 use constant_condition::{ConstantCondition, ConstantConditionValue};
 use constant_value::ConstantValue;
 use indexmap::IndexSet;
@@ -194,7 +194,10 @@ impl AnalyzeEcmascriptModuleResultBuilder {
  }
 
  /// Adds an asset reference to the analysis result.
- pub fn add_import_reference(&mut self, reference: Vc<EsmAssetReference>) {
+ pub fn add_import_reference<R>(&mut self, reference: Vc<R>)
+ where
+ R: Upcast<Box<dyn ModuleReference>>,
+ {
  self.references.insert(Vc::upcast(reference));
  }
 
@@ -576,7 +579,10 @@ pub(crate) async fn analyse_ecmascript_module_internal(
  Some(ModulePart::evaluation())
  }
  ImportedSymbol::Symbol(name) => Some(ModulePart::export((&**name).into())),
- ImportedSymbol::Part(part_id) => Some(ModulePart::internal(*part_id)),
+ ImportedSymbol::Part(part_id) => {
+ evaluation_references.push(i);
+ Some(ModulePart::internal(*part_id))
+ }
  ImportedSymbol::Exports => Some(ModulePart::exports()),
  },
  Some(TreeShakingMode::ReexportsOnly) => match &r.imported_symbol {
@@ -585,10 +591,15 @@ pub(crate) async fn analyse_ecmascript_module_internal(
  Some(ModulePart::evaluation())
  }
  ImportedSymbol::Symbol(name) => Some(ModulePart::export((&**name).into())),
- ImportedSymbol::Part(part_id) => Some(ModulePart::internal(*part_id)),
+ ImportedSymbol::Part(_) => {
+ bail!("Internal imports doesn't exist in reexports only mode")
+ }
  ImportedSymbol::Exports => None,
  },
- None => None,
+ None => {
+ evaluation_references.push(i);
+ None
+ }
  },
  special_exports,
  import_externals,
@@ -603,12 +614,10 @@ pub(crate) async fn analyse_ecmascript_module_internal(
  *r = r.resolve().await?;
  }
 
- for r in import_references.iter() {
- // `add_import_reference` will avoid adding duplicate references
- analysis.add_import_reference(*r);
- }
  for i in evaluation_references {
- analysis.add_evaluation_reference(import_references[i]);
+ let reference = import_references[i];
+ analysis.add_evaluation_reference(reference);
+ analysis.add_import_reference(reference);
  }
 
  let (webpack_runtime, webpack_entry, webpack_chunks, esm_exports, esm_star_exports) =
@@ -661,15 +670,18 @@ pub(crate) async fn analyse_ecmascript_module_internal(
  EsmExport::LocalBinding(..) => {}
  EsmExport::ImportedNamespace(reference) => {
  analysis.add_reexport_reference(reference);
+ analysis.add_import_reference(reference);
  }
  EsmExport::ImportedBinding(reference, ..) => {
  analysis.add_reexport_reference(reference);
+ analysis.add_import_reference(reference);
  }
  EsmExport::Error => {}
  }
  }
  for &export in esm_star_exports.iter() {
  analysis.add_reexport_reference(export);
+ analysis.add_import_reference(export);
  }
 
  let mut ignore_effect_span = None;
@@ -1076,6 +1088,7 @@ pub(crate) async fn analyse_ecmascript_module_internal(
  .add_reference(EsmModuleIdAssetReference::new(*r, Vc::cell(ast_path)))
  } else {
  analysis.add_local_reference(*r);
+ analysis.add_import_reference(*r);
  analysis.add_binding(EsmBinding::new(*r, export, Vc::cell(ast_path)));
  }
  }