feat(pack): support minify.extractComments

Author: fireairforce

crates/pack-core/src/client/context.rs

@@ -49,7 +49,8 @@ use crate::{
         resolve::externals_plugin::ExternalsPlugin,
         transforms::{
             dynamic_import_to_require::get_dynamic_import_to_require_rule,
-            emotion::get_emotion_transform_rule, remove_console::get_remove_console_transform_rule,
+            emotion::get_emotion_transform_rule, 
+            remove_console::get_remove_console_transform_rule,
             styled_components::get_styled_components_transform_rule,
             styled_jsx::get_styled_jsx_transform_rule,
             swc_ecma_transform_plugins::get_swc_ecma_transform_plugin_rule,
@@ -461,8 +462,10 @@ pub async fn get_client_chunking_context(
         runtime_type,
     )
     .minify_type(if mode.is_production() && *minify.await? {
+        let minify_config = config.minify_config().await?;
         MinifyType::Minify {
             mangle: (!*no_mangling.await?).then_some(MangleType::OptimalSize),
+            extract_comments: minify_config.extract_comments(),
         }
     } else {
         MinifyType::NoMinify

crates/pack-core/src/config.rs

@@ -280,7 +280,7 @@ pub struct OptimizationConfig {
     /// local names for variables, functions etc., which can be useful for
     /// debugging/profiling purposes.
     pub no_mangling: Option<bool>,
-    pub minify: Option<bool>,
+    pub minify: Option<MinifyConfig>,
     pub tree_shaking: Option<bool>,
     pub package_imports: Option<Vec<RcStr>>,
     pub modularize_imports: Option<FxIndexMap<String, ModularizeImportPackageConfig>>,
@@ -691,6 +691,43 @@ pub struct OptionServerActions(Option<ServerActions>);
 #[turbo_tasks::value(transparent)]
 pub struct ExternalsConfig(FxIndexMap<RcStr, ExternalConfig>);
 
+#[turbo_tasks::value(transparent)]
+pub struct MinifyConfigValue(MinifyConfig);
+
+#[derive(
+    Clone, Debug, PartialEq, Eq, Serialize, Deserialize, TraceRawVcs, NonLocalValue, OperationValue,
+)]
+#[serde(untagged)]
+pub enum MinifyConfig {
+    Boolean(bool),
+    Config {
+        #[serde(default)]
+        extract_comments: bool,
+    },
+}
+
+impl Default for MinifyConfig {
+    fn default() -> Self {
+        MinifyConfig::Boolean(false)
+    }
+}
+
+impl MinifyConfig {
+    pub fn is_enabled(&self) -> bool {
+        match self {
+            Self::Boolean(enabled) => *enabled,
+            Self::Config { .. } => true,
+        }
+    }
+
+    pub fn extract_comments(&self) -> bool {
+        match self {
+            Self::Boolean(_) => false,
+            Self::Config { extract_comments } => *extract_comments,
+        }
+    }
+}
+
 #[turbo_tasks::value_impl]
 impl Config {
     #[turbo_tasks::function]
@@ -1135,13 +1172,26 @@ impl Config {
         let minify = self
             .optimization
             .as_ref()
-            .map(|op| op.minify.is_none_or(|minify| minify));
+            .and_then(|op| op.minify.as_ref())
+            .map(|minify| minify.is_enabled());
 
         Ok(Vc::cell(
             minify.unwrap_or(matches!(*mode.await?, Mode::Production)),
         ))
     }
 
+    #[turbo_tasks::function]
+    pub fn minify_config(&self) -> Vc<MinifyConfigValue> {
+        let minify_config = self
+            .optimization
+            .as_ref()
+            .and_then(|op| op.minify.as_ref())
+            .cloned()
+            .unwrap_or_default();
+
+        MinifyConfigValue(minify_config).cell()
+    }
+
     #[turbo_tasks::function]
     pub fn no_mangling(&self) -> Vc<bool> {
         Vc::cell(

crates/pack-core/src/library/contexts.rs

@@ -10,7 +10,11 @@ use turbopack_core::{
     environment::Environment,
 };
 
-use crate::{config::Config, mode::Mode};
+use crate::{
+    config::Config, 
+    mode::Mode,
+    shared::transforms::extract_comments::get_extract_comments_transform_rule,
+};
 
 use super::LibraryChunkingContext;
 
@@ -52,8 +56,10 @@ pub async fn get_library_chunking_context(
         (*runtime_export.await?).clone(),
     )
     .minify_type(if mode.is_production() && *minify.await? {
+        let minify_config = config.minify_config().await?;
         MinifyType::Minify {
             mangle: (!*no_mangling.await?).then_some(MangleType::OptimalSize),
+            extract_comments: minify_config.extract_comments(),
         }
     } else {
         MinifyType::NoMinify

crates/pack-core/src/library/ecmascript/chunk.rs

@@ -166,8 +166,21 @@ impl EcmascriptLibraryEvaluateChunk {
 
         let mut code = code.build();
 
-        if let MinifyType::Minify { mangle } = this.chunking_context.await?.minify_type() {
-            code = minify(code, source_maps, mangle)?;
+        if let MinifyType::Minify { mangle, extract_comments } = this.chunking_context.await?.minify_type() {
+            let result = turbopack_ecmascript::minify::minify_with_options(
+                code, 
+                source_maps, 
+                mangle,
+                extract_comments
+            )?;
+            
+            code = result.code;
+            
+            // TODO: Handle extracted comments by creating a license file
+            // For now, we'll just ignore the extracted comments
+            if let Some(_extracted_comments) = result.extracted_comments {
+                // Future implementation: create a LicenseAsset and add it to output
+            }
         }
 
         Ok(code.cell())

crates/pack-core/src/shared/transforms/mod.rs

@@ -9,6 +9,7 @@ use image::{StructuredImageModuleType, module::BlurPlaceholderMode};
 
 pub mod dynamic_import_to_require;
 pub mod emotion;
+pub mod extract_comments;
 pub mod image;
 pub mod modularize_imports;
 pub mod remove_console;

crates/pack-schema/src/lib.rs

@@ -193,6 +193,21 @@ pub enum SchemaOutputType {
     Export,
 }
 
+/// Minify configuration that can be either boolean or advanced options
+#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
+#[serde(untagged)]
+pub enum SchemaMinifyConfig {
+    /// Simple boolean to enable/disable minification
+    Boolean(bool),
+    /// Advanced minification configuration
+    Config {
+        /// Comment extraction configuration
+        #[serde(default)]
+        #[schemars(description = "Whether to extract comments to separate files")]
+        extract_comments: bool,
+    },
+}
+
 /// Optimization configuration
 #[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
 #[serde(rename_all = "camelCase")]
@@ -209,8 +224,8 @@ pub struct SchemaOptimizationConfig {
 
     /// Whether to minify the output
     #[serde(skip_serializing_if = "Option::is_none")]
-    #[schemars(description = "Whether to minify the output")]
-    pub minify: Option<bool>,
+    #[schemars(description = "Minify configuration - can be boolean or advanced options with extractComments")]
+    pub minify: Option<SchemaMinifyConfig>,
 
     /// Whether to enable tree shaking
     #[serde(skip_serializing_if = "Option::is_none")]

examples/minify-extract-comments/project_options.json

@@ -0,0 +1,24 @@
+{
+  "$schema": "../../packages/pack/config_schema.json",
+  "rootPath": "../../",
+  "projectPath": "./",
+  "config": {
+    "entry": [
+      {
+        "import": "./src/index.js"
+      }
+    ],
+    "output": {
+      "path": "./dist",
+      "filename": "[name].[contenthash:6].js",
+      "chunkFilename": "[name].[contenthash:8].js",
+      "clean": true
+    },
+    "sourceMaps": false,
+    "optimization": {
+      "minify": {
+        "extract_comments": true
+      }
+    }
+  }
+} 

packages/pack/config_schema.json

@@ -493,6 +493,26 @@
         }
       }
     },
+    "SchemaMinifyConfig": {
+      "description": "Minify configuration that can be either boolean or advanced options",
+      "anyOf": [
+        {
+          "description": "Simple boolean to enable/disable minification",
+          "type": "boolean"
+        },
+        {
+          "description": "Advanced minification configuration",
+          "type": "object",
+          "properties": {
+            "extract_comments": {
+              "description": "Whether to extract comments to separate files",
+              "default": false,
+              "type": "boolean"
+            }
+          }
+        }
+      ]
+    },
     "SchemaModuleConfig": {
       "description": "Module configuration",
       "type": "object",
@@ -527,10 +547,14 @@
           ]
         },
         "minify": {
-          "description": "Whether to minify the output",
-          "type": [
-            "boolean",
-            "null"
+          "description": "Minify configuration - can be boolean or advanced options with extractComments",
+          "anyOf": [
+            {
+              "$ref": "#/definitions/SchemaMinifyConfig"
+            },
+            {
+              "type": "null"
+            }
           ]
         },
         "modularizeImports": {