feat(stats): add module reason locations and module trace dependencies

crates/node_binding/binding.d.ts

@@ -1043,11 +1043,19 @@ export interface JsStatsModuleReason {
   moduleChunks?: number
   type?: string
   userRequest?: string
+  explanation?: string
+  active: boolean
+  loc?: string
 }
 
 export interface JsStatsModuleTrace {
   origin: JsStatsModuleTraceModule
   module: JsStatsModuleTraceModule
+  dependencies: Array<JsStatsModuleTraceDependency>
+}
+
+export interface JsStatsModuleTraceDependency {
+  loc: string
 }
 
 export interface JsStatsModuleTraceModule {

crates/rspack_binding_values/src/stats.rs

@@ -157,13 +157,15 @@ impl From<rspack_core::StatsWarning<'_>> for JsStatsWarning {
 pub struct JsStatsModuleTrace {
   pub origin: JsStatsModuleTraceModule,
   pub module: JsStatsModuleTraceModule,
+  pub dependencies: Vec<JsStatsModuleTraceDependency>,
 }
 
 impl From<rspack_core::StatsModuleTrace> for JsStatsModuleTrace {
   fn from(stats: rspack_core::StatsModuleTrace) -> Self {
     Self {
       origin: stats.origin.into(),
       module: stats.module.into(),
+      dependencies: stats.dependencies.into_iter().map(Into::into).collect(),
     }
   }
 }
@@ -187,6 +189,17 @@ impl From<rspack_core::StatsErrorModuleTraceModule> for JsStatsModuleTraceModule
   }
 }
 
+#[napi(object, object_from_js = false)]
+pub struct JsStatsModuleTraceDependency {
+  pub loc: String,
+}
+
+impl From<rspack_core::StatsErrorModuleTraceDependency> for JsStatsModuleTraceDependency {
+  fn from(stats: rspack_core::StatsErrorModuleTraceDependency) -> Self {
+    Self { loc: stats.loc }
+  }
+}
+
 #[napi(object, object_from_js = false)]
 pub struct JsStatsLogging {
   pub name: String,
@@ -673,6 +686,9 @@ pub struct JsStatsModuleReason {
   pub module_chunks: Option<u32>,
   pub r#type: Option<&'static str>,
   pub user_request: Option<String>,
+  pub explanation: Option<&'static str>,
+  pub active: bool,
+  pub loc: Option<String>,
 }
 
 impl From<rspack_core::StatsModuleReason<'_>> for JsStatsModuleReason {
@@ -697,6 +713,9 @@ impl From<rspack_core::StatsModuleReason<'_>> for JsStatsModuleReason {
       module_chunks: stats.module_chunks,
       r#type: stats.r#type,
       user_request: stats.user_request.map(|i| i.to_owned()),
+      explanation: stats.explanation,
+      active: stats.active,
+      loc: stats.loc,
     }
   }
 }

crates/rspack_core/src/module_graph/mod.rs

@@ -28,6 +28,7 @@ pub type ImportVarMap =
 #[derive(Debug)]
 pub struct DependencyExtraMeta {
   pub ids: Vec<Atom>,
+  pub explanation: Option<&'static str>,
 }
 
 #[derive(Debug, Default, Clone)]

crates/rspack_core/src/stats/mod.rs

@@ -946,6 +946,10 @@ impl Stats<'_> {
             } else {
               (None, None)
             };
+          let loc = dependency.and_then(|d| d.loc()).map(|l| l.to_string());
+          let explanation = module_graph
+            .get_dep_meta_if_existing(&connection.dependency_id)
+            .and_then(|extra| extra.explanation);
           Some(StatsModuleReason {
             module_identifier: connection.original_module_identifier,
             module_name,
@@ -967,6 +971,9 @@ impl Stats<'_> {
             resolved_module_id: resolved_module_id.and_then(|i| i),
             r#type,
             user_request,
+            explanation,
+            active: connection.active,
+            loc,
           })
         })
         .collect();

crates/rspack_core/src/stats/struct.rs

@@ -78,6 +78,7 @@ pub struct StatsWarning<'s> {
 pub struct StatsModuleTrace {
   pub origin: StatsErrorModuleTraceModule,
   pub module: StatsErrorModuleTraceModule,
+  pub dependencies: Vec<StatsErrorModuleTraceDependency>,
 }
 
 #[derive(Debug)]
@@ -87,6 +88,11 @@ pub struct StatsErrorModuleTraceModule {
   pub id: Option<String>,
 }
 
+#[derive(Debug)]
+pub struct StatsErrorModuleTraceDependency {
+  pub loc: String,
+}
+
 #[derive(Debug)]
 pub struct StatsAsset {
   pub r#type: &'static str,
@@ -267,6 +273,9 @@ pub struct StatsModuleReason<'s> {
 
   pub r#type: Option<&'static str>,
   pub user_request: Option<&'s str>,
+  pub explanation: Option<&'static str>,
+  pub active: bool,
+  pub loc: Option<String>,
 }
 
 #[derive(Debug)]

crates/rspack_core/src/stats/utils.rs

@@ -5,7 +5,10 @@ use rayon::iter::{IntoParallelRefIterator, ParallelIterator};
 use rspack_collections::Identifier;
 use rustc_hash::{FxHashMap as HashMap, FxHashSet as HashSet};
 
-use super::{Stats, StatsChunkGroup, StatsErrorModuleTraceModule, StatsModule, StatsModuleTrace};
+use super::{
+  Stats, StatsChunkGroup, StatsErrorModuleTraceDependency, StatsErrorModuleTraceModule,
+  StatsModule, StatsModuleTrace,
+};
 use crate::{
   BoxModule, Chunk, ChunkByUkey, ChunkGraph, ChunkGroupByUkey, ChunkGroupOrderKey, ChunkGroupUkey,
   Compilation, CompilerOptions, ModuleGraph,
@@ -189,10 +192,19 @@ pub fn get_module_trace(
       )
       .map(|s| s.to_string()),
     };
+    let dependencies = module_graph
+      .get_incoming_connections(&module_identifier)
+      .filter_map(|c| {
+        let dep = module_graph.dependency_by_id(&c.dependency_id)?;
+        let loc = dep.loc().map(|loc| loc.to_string())?;
+        Some(StatsErrorModuleTraceDependency { loc })
+      })
+      .collect::<Vec<_>>();
 
     module_trace.push(StatsModuleTrace {
       origin: origin_stats_module,
       module: current_stats_module,
+      dependencies,
     });
 
     current_module_identifier = Some(origin_module.identifier());

crates/rspack_plugin_javascript/src/plugin/side_effects_flag_plugin.rs

@@ -822,7 +822,13 @@ fn do_optimize_connection(
     need_move_target,
   } = do_optimize;
   module_graph.do_update_module(&dependency, &target_module);
-  module_graph.set_dependency_extra_meta(dependency, DependencyExtraMeta { ids });
+  module_graph.set_dependency_extra_meta(
+    dependency,
+    DependencyExtraMeta {
+      ids,
+      explanation: Some("(skipped side-effect-free modules)"),
+    },
+  );
   if let Some(SideEffectsDoOptimizeMoveTarget {
     export_info,
     target_export,