turbopack_node/transforms/

webpack.rs

use std::mem::take;

use anyhow::{Context, Result, bail};
use async_trait::async_trait;
use base64::Engine;
use bincode::{Decode, Encode};
use either::Either;
use futures::try_join;
use serde::{Deserialize, Serialize};
use serde_json::{Map as JsonMap, Value as JsonValue, json};
use serde_with::serde_as;
use tracing::Instrument;
use turbo_rcstr::{RcStr, rcstr};
use turbo_tasks::{
    Completion, OperationVc, ReadRef, ResolvedVc, TaskInput, TryJoinIterExt, ValueToString,
    ValueToStringRef, Vc, trace::TraceRawVcs,
};
use turbo_tasks_env::ProcessEnv;
use turbo_tasks_fs::{
    File, FileContent, FileSystemPath,
    glob::{Glob, GlobOptions},
    json::parse_json_with_source_context,
    rope::Rope,
};
use turbopack_core::{
    asset::{Asset, AssetContent},
    chunk::{ChunkingContext, ChunkingContextExt, EvaluatableAsset},
    context::{AssetContext, ProcessResult},
    file_source::FileSource,
    ident::AssetIdent,
    issue::{Issue, IssueExt, IssueSeverity, IssueSource, IssueStage, StyledString},
    module_graph::{
        ModuleGraph, SingleModuleGraph,
        chunk_group_info::{ChunkGroup, ChunkGroupEntry},
    },
    output::{ExpandOutputAssetsInput, OutputAsset, OutputAssets, expand_output_assets},
    reference_type::{EcmaScriptModulesReferenceSubType, InnerAssets, ReferenceType},
    resolve::{
        ResolveErrorMode,
        options::{ConditionValue, ResolveInPackage, ResolveIntoPackage, ResolveOptions},
        origin::PlainResolveOrigin,
        parse::Request,
        pattern::Pattern,
        resolve,
    },
    source::Source,
    source_map::{GenerateSourceMap, utils::resolve_source_map_sources},
    source_transform::SourceTransform,
    virtual_source::VirtualSource,
};
use turbopack_resolve::{
    ecmascript::{esm_resolve, get_condition_maps},
    resolve::resolve_options,
    resolve_options_context::ResolveOptionsContext,
};

use crate::{
    AssetsForSourceMapping,
    backend::NodeBackend,
    debug::should_debug,
    embed_js::embed_file_path,
    evaluate::{
        EnvVarTracking, EvaluateContext, EvaluateEntries, EvaluatePool, EvaluationIssue,
        custom_evaluate, get_evaluate_entries, get_evaluate_pool,
    },
    execution_context::ExecutionContext,
    format::FormattingMode,
    source_map::{StackFrame, StructuredError},
    transforms::util::{EmittedAsset, emitted_assets_to_virtual_sources},
};

#[serde_as]
#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Deserialize, Encode, Decode)]
struct BytesBase64 {
    #[serde_as(as = "serde_with::base64::Base64")]
    binary: Vec<u8>,
}

#[derive(Debug, Clone, Deserialize)]
#[turbo_tasks::value]
#[serde(rename_all = "camelCase")]
struct WebpackLoadersProcessingResult {
    #[serde(with = "either::serde_untagged")]
    #[bincode(with = "turbo_bincode::either")]
    #[turbo_tasks(debug_ignore, trace_ignore)]
    source: Either<RcStr, BytesBase64>,
    map: Option<RcStr>,
    #[turbo_tasks(trace_ignore)]
    assets: Option<Vec<EmittedAsset>>,
}

pub use turbopack_core::loader::{WebpackLoaderItem, WebpackLoaderItems};

#[turbo_tasks::value]
pub struct WebpackLoaders {
    evaluate_context: ResolvedVc<Box<dyn AssetContext>>,
    execution_context: ResolvedVc<ExecutionContext>,
    loaders: ResolvedVc<WebpackLoaderItems>,
    rename_as: Option<RcStr>,
    resolve_options_context: ResolvedVc<ResolveOptionsContext>,
    source_maps: bool,
}

#[turbo_tasks::value_impl]
impl WebpackLoaders {
    #[turbo_tasks::function]
    pub fn new(
        evaluate_context: ResolvedVc<Box<dyn AssetContext>>,
        execution_context: ResolvedVc<ExecutionContext>,
        loaders: ResolvedVc<WebpackLoaderItems>,
        rename_as: Option<RcStr>,
        resolve_options_context: ResolvedVc<ResolveOptionsContext>,
        source_maps: bool,
    ) -> Vc<Self> {
        WebpackLoaders {
            evaluate_context,
            execution_context,
            loaders,
            rename_as,
            resolve_options_context,
            source_maps,
        }
        .cell()
    }
}

#[turbo_tasks::value_impl]
impl SourceTransform for WebpackLoaders {
    #[turbo_tasks::function]
    fn transform(
        self: ResolvedVc<Self>,
        source: ResolvedVc<Box<dyn Source>>,
        asset_context: ResolvedVc<Box<dyn AssetContext>>,
    ) -> Vc<Box<dyn Source>> {
        Vc::upcast(
            WebpackLoadersProcessedAsset {
                transform: self,
                source,
                asset_context,
            }
            .cell(),
        )
    }
}

#[turbo_tasks::value]
struct WebpackLoadersProcessedAsset {
    transform: ResolvedVc<WebpackLoaders>,
    source: ResolvedVc<Box<dyn Source>>,
    asset_context: ResolvedVc<Box<dyn AssetContext>>,
}

#[turbo_tasks::value_impl]
impl Source for WebpackLoadersProcessedAsset {
    #[turbo_tasks::function]
    async fn ident(&self) -> Result<Vc<AssetIdent>> {
        Ok(
            if let Some(rename_as) = self.transform.await?.rename_as.as_deref() {
                self.source.ident().rename_as(rename_as.into())
            } else {
                self.source.ident()
            },
        )
    }

    #[turbo_tasks::function]
    async fn description(&self) -> Result<Vc<RcStr>> {
        let inner = self.source.description().await?;
        let loaders = self.transform.await?.loaders.await?;
        let loader_names: Vec<&str> = loaders.iter().map(|l| l.loader.as_str()).collect();
        Ok(Vc::cell(
            format!(
                "loaders [{}] transform of {}",
                loader_names.join(", "),
                inner
            )
            .into(),
        ))
    }
}

#[turbo_tasks::value_impl]
impl Asset for WebpackLoadersProcessedAsset {
    #[turbo_tasks::function]
    async fn content(self: Vc<Self>) -> Result<Vc<AssetContent>> {
        Ok(*self.process().await?.content)
    }
}

#[turbo_tasks::value_impl]
impl GenerateSourceMap for WebpackLoadersProcessedAsset {
    #[turbo_tasks::function]
    async fn generate_source_map(self: Vc<Self>) -> Result<Vc<FileContent>> {
        Ok(*self.process().await?.source_map)
    }
}

#[turbo_tasks::value]
struct ProcessWebpackLoadersResult {
    content: ResolvedVc<AssetContent>,
    source_map: ResolvedVc<FileContent>,
    assets: Vec<ResolvedVc<VirtualSource>>,
}

#[turbo_tasks::function]
async fn webpack_loaders_executor(
    evaluate_context: Vc<Box<dyn AssetContext>>,
) -> Result<Vc<ProcessResult>> {
    Ok(evaluate_context.process(
        Vc::upcast(FileSource::new(
            embed_file_path(rcstr!("transforms/webpack-loaders.ts"))
                .owned()
                .await?,
        )),
        ReferenceType::Internal(InnerAssets::empty().to_resolved().await?),
    ))
}

#[turbo_tasks::value_impl]
impl WebpackLoadersProcessedAsset {
    #[turbo_tasks::function]
    async fn process(&self) -> Result<Vc<ProcessWebpackLoadersResult>> {
        let transform = self.transform.await?;
        let loaders = transform.loaders.await?;

        let webpack_span = tracing::info_span!(
            "webpack loader",
            name = display(ReadRef::<WebpackLoaderItems>::as_raw_ref(&loaders))
        );

        async {
            let ExecutionContext {
                project_path,
                chunking_context,
                env,
                node_backend,
            } = &*transform.execution_context.await?;
            let source_content = self.source.content();
            let AssetContent::File(file) = *source_content.await? else {
                bail!("Webpack Loaders transform only support transforming files");
            };
            let FileContent::Content(file_content) = &*file.await? else {
                return Ok(ProcessWebpackLoadersResult {
                    content: AssetContent::File(FileContent::NotFound.resolved_cell())
                        .resolved_cell(),
                    assets: Vec::new(),
                    source_map: FileContent::NotFound.resolved_cell(),
                }
                .cell());
            };

            // If the content is not a valid string (e.g. binary file), handle the error and pass a
            // Buffer to Webpack instead of a Base64 string so the build process doesn't crash.
            let content: JsonValue = match file_content.content().to_str() {
                Ok(utf8_str) => utf8_str.to_string().into(),
                Err(_) => JsonValue::Object(JsonMap::from_iter(std::iter::once((
                    "binary".to_string(),
                    JsonValue::from(
                        base64::engine::general_purpose::STANDARD
                            .encode(file_content.content().to_bytes()),
                    ),
                )))),
            };
            let evaluate_context = transform.evaluate_context;

            let webpack_loaders_executor = webpack_loaders_executor(*evaluate_context).module();

            let entries = get_evaluate_entries(
                webpack_loaders_executor,
                *evaluate_context,
                **node_backend,
                None,
            )
            .to_resolved()
            .await?;

            let module_graph = ModuleGraph::from_graphs(
                vec![SingleModuleGraph::new_with_entries(
                    entries.graph_entries().to_resolved().await?,
                    false,
                    false,
                )],
                None,
            )
            .connect()
            .to_resolved()
            .await?;

            let resource_fs_path = self.source.ident().path().await?;
            let Some(resource_path) = project_path.get_relative_path_to(&resource_fs_path) else {
                bail!(
                    "Resource path \"{}\" needs to be on project filesystem \"{}\"",
                    resource_fs_path,
                    project_path
                );
            };
            let config_value = evaluate_webpack_loader(WebpackLoaderContext {
                entries,
                cwd: project_path.clone(),
                env: *env,
                node_backend: *node_backend,
                context_source_for_issue: self.source,
                chunking_context: *chunking_context,
                evaluate_context: transform.evaluate_context,
                module_graph,
                resolve_options_context: Some(transform.resolve_options_context),
                asset_context: self.asset_context,
                args: vec![
                    ResolvedVc::cell(content),
                    // We need to pass the query string to the loader
                    ResolvedVc::cell(resource_path.to_string().into()),
                    ResolvedVc::cell(self.source.ident().await?.query.to_string().into()),
                    ResolvedVc::cell(json!(*loaders)),
                    ResolvedVc::cell(transform.source_maps.into()),
                ],
                additional_invalidation: Completion::immutable().to_resolved().await?,
            })
            .await?;

            let Some(val) = &*config_value else {
                // An error happened, which has already been converted into an issue.
                return Ok(ProcessWebpackLoadersResult {
                    content: AssetContent::File(FileContent::NotFound.resolved_cell())
                        .resolved_cell(),
                    assets: Vec::new(),
                    source_map: FileContent::NotFound.resolved_cell(),
                }
                .cell());
            };
            let processed: WebpackLoadersProcessingResult = parse_json_with_source_context(val)
                .context(
                    "Unable to deserializate response from webpack loaders transform operation",
                )?;

            // handle SourceMap
            let source_map = if !transform.source_maps {
                None
            } else {
                processed
                    .map
                    .map(|source_map| Rope::from(source_map.into_owned()))
            };
            let source_map =
                resolve_source_map_sources(source_map.as_ref(), &resource_fs_path).await?;

            let file = match processed.source {
                Either::Left(str) => File::from(str),
                Either::Right(bytes) => File::from(bytes.binary),
            };
            let assets = emitted_assets_to_virtual_sources(processed.assets).await?;

            let content =
                AssetContent::File(FileContent::Content(file).resolved_cell()).resolved_cell();
            Ok(ProcessWebpackLoadersResult {
                content,
                assets,
                source_map: if let Some(source_map) = source_map {
                    FileContent::Content(File::from(source_map)).resolved_cell()
                } else {
                    FileContent::NotFound.resolved_cell()
                },
            }
            .cell())
        }
        .instrument(webpack_span)
        .await
    }
}

#[turbo_tasks::function]
pub(crate) async fn evaluate_webpack_loader(
    webpack_loader_context: WebpackLoaderContext,
) -> Result<Vc<Option<RcStr>>> {
    custom_evaluate(webpack_loader_context).await
}

#[derive(Deserialize, Debug, PartialEq, Eq, Encode, Decode)]
#[serde(rename_all = "camelCase")]
enum LogType {
    Error,
    Warn,
    Info,
    Log,
    Debug,
    Trace,
    Group,
    GroupCollapsed,
    GroupEnd,
    Profile,
    ProfileEnd,
    Time,
    Clear,
    Status,
}

#[derive(Deserialize, Debug, PartialEq, Eq, Encode, Decode)]
#[serde(rename_all = "camelCase")]
pub struct LogInfo {
    time: u64,
    log_type: LogType,
    #[bincode(with = "turbo_bincode::serde_self_describing")]
    args: Vec<JsonValue>,
    trace: Option<Vec<StackFrame<'static>>>,
}

#[derive(Deserialize, Debug)]
#[serde(tag = "type", rename_all = "camelCase")]
pub enum InfoMessage {
    // Sent to inform Turbopack about the dependencies of the task.
    // All fields are `default` since it is ok for the client to
    // simply omit instead of sending empty arrays.
    #[serde(rename_all = "camelCase")]
    Dependencies {
        #[serde(default)]
        env_variables: Vec<RcStr>,
        #[serde(default)]
        file_paths: Vec<RcStr>,
        #[serde(default)]
        directories: Vec<(RcStr, RcStr)>,
        #[serde(default)]
        build_file_paths: Vec<RcStr>,
    },
    EmittedError {
        severity: IssueSeverity,
        error: StructuredError,
    },
    Log {
        logs: Vec<LogInfo>,
    },
}

#[derive(
    Debug, Clone, TaskInput, Hash, PartialEq, Eq, Deserialize, TraceRawVcs, Encode, Decode,
)]
#[serde(rename_all = "camelCase")]
pub struct WebpackResolveOptions {
    alias_fields: Option<Vec<RcStr>>,
    condition_names: Option<Vec<RcStr>>,
    no_package_json: bool,
    extensions: Option<Vec<RcStr>>,
    main_fields: Option<Vec<RcStr>>,
    no_exports_field: bool,
    main_files: Option<Vec<RcStr>>,
    no_modules: bool,
    prefer_relative: bool,
}

#[derive(Deserialize, Debug)]
#[serde(tag = "type", rename_all = "camelCase")]
pub enum RequestMessage {
    #[serde(rename_all = "camelCase")]
    Resolve {
        options: WebpackResolveOptions,
        lookup_path: RcStr,
        request: RcStr,
    },
    #[serde(rename_all = "camelCase")]
    TrackFileRead { file: RcStr },
    #[serde(rename_all = "camelCase")]
    ImportModule { lookup_path: RcStr, request: RcStr },
}

#[derive(Serialize, Debug)]
#[serde(rename_all = "camelCase")]
pub struct ImportModuleChunk {
    path: RcStr,
    #[serde(skip_serializing_if = "Option::is_none")]
    code: Option<RcStr>,
    #[serde(skip_serializing_if = "Option::is_none")]
    binary: Option<String>,
    #[serde(skip_serializing_if = "Option::is_none")]
    source_map: Option<RcStr>,
}

#[derive(Serialize, Debug)]
#[serde(untagged)]
pub enum ResponseMessage {
    Resolve {
        path: RcStr,
    },
    // Only used for tracking invalidations, no content is returned.
    TrackFileRead {},
    #[serde(rename_all = "camelCase")]
    ImportModule {
        entry_path: RcStr,
        chunks: Vec<ImportModuleChunk>,
    },
}

#[derive(Clone, PartialEq, Eq, Hash, TaskInput, Debug, TraceRawVcs, Encode, Decode)]
pub struct WebpackLoaderContext {
    pub entries: ResolvedVc<EvaluateEntries>,
    pub cwd: FileSystemPath,
    pub env: ResolvedVc<Box<dyn ProcessEnv>>,
    pub node_backend: ResolvedVc<Box<dyn NodeBackend>>,
    pub context_source_for_issue: ResolvedVc<Box<dyn Source>>,
    pub module_graph: ResolvedVc<ModuleGraph>,
    pub chunking_context: ResolvedVc<Box<dyn ChunkingContext>>,
    pub evaluate_context: ResolvedVc<Box<dyn AssetContext>>,
    pub resolve_options_context: Option<ResolvedVc<ResolveOptionsContext>>,
    pub asset_context: ResolvedVc<Box<dyn AssetContext>>,
    pub args: Vec<ResolvedVc<JsonValue>>,
    pub additional_invalidation: ResolvedVc<Completion>,
}

impl EvaluateContext for WebpackLoaderContext {
    type InfoMessage = InfoMessage;
    type RequestMessage = RequestMessage;
    type ResponseMessage = ResponseMessage;
    type State = Vec<LogInfo>;

    fn pool(&self) -> OperationVc<EvaluatePool> {
        get_evaluate_pool(
            self.entries,
            self.cwd.clone(),
            self.env,
            self.node_backend,
            self.chunking_context,
            self.module_graph,
            self.additional_invalidation,
            should_debug("webpack_loader"),
            // Env vars are read untracked, since we want a more granular dependency on certain env
            // vars only. So the runtime code tracks which env vars are read and send a dependency
            // message for them.
            EnvVarTracking::Untracked,
        )
    }

    fn args(&self) -> &[ResolvedVc<serde_json::Value>] {
        &self.args
    }

    fn cwd(&self) -> Vc<turbo_tasks_fs::FileSystemPath> {
        self.cwd.clone().cell()
    }

    fn keep_alive(&self) -> bool {
        true
    }

    async fn emit_error(&self, error: StructuredError, pool: &EvaluatePool) -> Result<()> {
        EvaluationIssue {
            error,
            source: IssueSource::from_source_only(self.context_source_for_issue),
            assets_for_source_mapping: pool.assets_for_source_mapping,
            assets_root: pool.assets_root.clone(),
            root_path: self.chunking_context.root_path().owned().await?,
        }
        .resolved_cell()
        .emit();
        Ok(())
    }

    async fn info(
        &self,
        state: &mut Self::State,
        data: Self::InfoMessage,
        pool: &EvaluatePool,
    ) -> Result<()> {
        match data {
            InfoMessage::Dependencies {
                env_variables,
                file_paths,
                directories,
                build_file_paths,
            } => {
                // We only process these dependencies to help with tracking, so if it is disabled
                // dont bother.
                if turbo_tasks::turbo_tasks().is_tracking_dependencies() {
                    // Track dependencies of the loader task
                    // TODO: Because these are reported _after_ the loader actually read the
                    // dependency there is a race condition where we may miss
                    // updates that race with the loader execution.

                    // Track all the subscriptions in parallel, since certain loaders like tailwind
                    // might add thousands of subscriptions.
                    let env_subscriptions = env_variables
                        .iter()
                        .map(|e| self.env.read(e.clone()))
                        .try_join();
                    let file_subscriptions = file_paths
                        .iter()
                        .map(|p| async move { self.cwd.join(p)?.read().await })
                        .try_join();
                    let directory_subscriptions = directories
                        .iter()
                        .map(|(dir, glob)| async move {
                            self.cwd
                                .join(dir)?
                                .track_glob(Glob::new(glob.clone(), GlobOptions::default()), false)
                                .await
                        })
                        .try_join();
                    try_join!(
                        env_subscriptions,
                        file_subscriptions,
                        directory_subscriptions
                    )?;

                    for build_path in build_file_paths {
                        let build_path = self.cwd.join(&build_path)?;
                        BuildDependencyIssue {
                            source: IssueSource::from_source_only(self.context_source_for_issue),
                            path: build_path,
                        }
                        .resolved_cell()
                        .emit();
                    }
                }
            }
            InfoMessage::EmittedError { error, severity } => {
                EvaluateEmittedErrorIssue {
                    source: IssueSource::from_source_only(self.context_source_for_issue),
                    error,
                    severity,
                    assets_for_source_mapping: pool.assets_for_source_mapping,
                    assets_root: pool.assets_root.clone(),
                    project_dir: self.chunking_context.root_path().owned().await?,
                }
                .resolved_cell()
                .emit();
            }
            InfoMessage::Log { logs } => {
                state.extend(logs);
            }
        }
        Ok(())
    }

    async fn request(
        &self,
        _state: &mut Self::State,
        data: Self::RequestMessage,
        _pool: &EvaluatePool,
    ) -> Result<Self::ResponseMessage> {
        match data {
            RequestMessage::Resolve {
                options: webpack_options,
                lookup_path,
                request,
            } => {
                let Some(resolve_options_context) = self.resolve_options_context else {
                    bail!("Resolve options are not available in this context");
                };
                let lookup_path = self.cwd.join(&lookup_path)?;
                let request = Request::parse(Pattern::Constant(request));
                let options = resolve_options(lookup_path.clone(), *resolve_options_context);

                let options = apply_webpack_resolve_options(options, webpack_options);

                let resolved = resolve(
                    lookup_path.clone(),
                    ReferenceType::Undefined,
                    request,
                    options,
                );

                if let Some(source) = *resolved.first_source().await? {
                    if let Some(path) = self
                        .cwd
                        .get_relative_path_to(&*source.ident().path().await?)
                    {
                        Ok(ResponseMessage::Resolve { path })
                    } else {
                        bail!(
                            "Resolving {} in {} ends up on a different filesystem",
                            request.to_string().await?,
                            lookup_path.to_string_ref().await?
                        );
                    }
                } else {
                    bail!(
                        "Unable to resolve {} in {}",
                        request.to_string().await?,
                        lookup_path.to_string_ref().await?
                    );
                }
            }
            RequestMessage::TrackFileRead { file } => {
                // Ignore result, we read on the JS side again to prevent some IPC overhead. Still
                // await the read though to cover at least one class of race conditions.
                let _ = &*self.cwd.join(&file)?.read().await?;
                Ok(ResponseMessage::TrackFileRead {})
            }
            RequestMessage::ImportModule {
                lookup_path,
                request,
            } => {
                let lookup_path = self.cwd.join(&lookup_path)?;

                let request_vc = Request::parse(Pattern::Constant(request.clone()));
                let origin = PlainResolveOrigin::new(*self.asset_context, lookup_path.join("_")?);
                let resolved = esm_resolve(
                    Vc::upcast(origin),
                    request_vc,
                    EcmaScriptModulesReferenceSubType::ImportModule,
                    ResolveErrorMode::Error,
                    Some(IssueSource::from_source_only(self.context_source_for_issue)),
                )
                .await?;

                let Some(module) = *resolved.first_module().await? else {
                    bail!(
                        "importModule: unable to resolve {} in {}",
                        request,
                        lookup_path.to_string_ref().await?
                    );
                };

                // Cast to evaluatable asset for bundle generation
                let evaluatable = ResolvedVc::try_sidecast::<Box<dyn EvaluatableAsset>>(module)
                    .context("importModule: module is not evaluatable")?;

                // Build a module graph from the resolved module and its
                // transitive dependencies
                let single_graph = SingleModuleGraph::new_with_entry(
                    ChunkGroupEntry::Entry(vec![module]),
                    false,
                    false,
                );
                let import_module_graph = ModuleGraph::from_graphs(vec![single_graph], None)
                    .connect()
                    .to_resolved()
                    .await?;

                // Generate a full Node.js bundle using the real runtime
                let output_root = self.chunking_context.output_root().owned().await?;
                let entry_path = output_root.join("importModule.js")?;

                let bootstrap = self.chunking_context.root_entry_chunk_group_asset(
                    entry_path.clone(),
                    ChunkGroup::Entry(vec![ResolvedVc::upcast(evaluatable)]),
                    *import_module_graph,
                    OutputAssets::empty(),
                    OutputAssets::empty(),
                );

                // Collect all internal assets as {path, code} pairs
                let bootstrap_resolved = bootstrap.to_resolved().await?;
                let all_assets = expand_output_assets(
                    std::iter::once(ExpandOutputAssetsInput::Asset(bootstrap_resolved)),
                    true,
                )
                .await?;

                let mut chunks = Vec::new();
                for asset in all_assets {
                    let asset_path = asset.path().owned().await?;
                    if !asset_path.is_inside_ref(&output_root) {
                        continue;
                    }
                    let Some(rel_path) = output_root.get_path_to(&asset_path) else {
                        continue;
                    };
                    // Skip source map files
                    if rel_path.ends_with(".map") {
                        continue;
                    }
                    let content = asset.content().await?;
                    let AssetContent::File(file_vc) = *content else {
                        continue;
                    };
                    let file_content = file_vc.await?;
                    let FileContent::Content(file) = &*file_content else {
                        continue;
                    };

                    if rel_path.ends_with(".js") {
                        // JavaScript chunk — send as text
                        let code: RcStr = file.content().to_str()?.into_owned().into();
                        chunks.push(ImportModuleChunk {
                            path: rel_path.into(),
                            code: Some(code),
                            binary: None,
                            source_map: None,
                        });
                    } else {
                        // Binary asset (wasm, images, etc.) — send base64-encoded
                        let bytes = file.content().to_bytes();
                        let encoded = base64::engine::general_purpose::STANDARD.encode(&*bytes);
                        chunks.push(ImportModuleChunk {
                            path: rel_path.into(),
                            code: None,
                            binary: Some(encoded),
                            source_map: None,
                        });
                    }
                }

                let entry_rel = output_root
                    .get_path_to(&entry_path)
                    .context("entry path should be inside output root")?;

                Ok(ResponseMessage::ImportModule {
                    entry_path: entry_rel.into(),
                    chunks,
                })
            }
        }
    }

    async fn finish(&self, state: Self::State, pool: &EvaluatePool) -> Result<()> {
        let has_errors = state.iter().any(|log| log.log_type == LogType::Error);
        let has_warnings = state.iter().any(|log| log.log_type == LogType::Warn);
        if has_errors || has_warnings {
            let logs = state
                .into_iter()
                .filter(|log| {
                    matches!(
                        log.log_type,
                        LogType::Error
                            | LogType::Warn
                            | LogType::Info
                            | LogType::Log
                            | LogType::Clear,
                    )
                })
                .collect();

            EvaluateErrorLoggingIssue {
                source: IssueSource::from_source_only(self.context_source_for_issue),
                logging: logs,
                severity: if has_errors {
                    IssueSeverity::Error
                } else {
                    IssueSeverity::Warning
                },
                assets_for_source_mapping: pool.assets_for_source_mapping,
                assets_root: pool.assets_root.clone(),
                project_dir: self.chunking_context.root_path().owned().await?,
            }
            .resolved_cell()
            .emit();
        }
        Ok(())
    }
}

#[turbo_tasks::function]
async fn apply_webpack_resolve_options(
    resolve_options: Vc<ResolveOptions>,
    webpack_resolve_options: WebpackResolveOptions,
) -> Result<Vc<ResolveOptions>> {
    let mut resolve_options = resolve_options.owned().await?;
    if let Some(alias_fields) = webpack_resolve_options.alias_fields {
        let mut old = resolve_options
            .in_package
            .extract_if(0.., |field| {
                matches!(field, ResolveInPackage::AliasField(..))
            })
            .collect::<Vec<_>>();
        for field in alias_fields {
            if &*field == "..." {
                resolve_options.in_package.extend(take(&mut old));
            } else {
                resolve_options
                    .in_package
                    .push(ResolveInPackage::AliasField(field));
            }
        }
    }
    if let Some(condition_names) = webpack_resolve_options.condition_names {
        for conditions in get_condition_maps(&mut resolve_options) {
            let mut old = take(conditions);
            for name in &condition_names {
                if name == "..." {
                    conditions.extend(take(&mut old));
                } else {
                    conditions.insert(name.clone(), ConditionValue::Set);
                }
            }
        }
    }
    if webpack_resolve_options.no_package_json {
        resolve_options.into_package.retain(|item| {
            !matches!(
                item,
                ResolveIntoPackage::ExportsField { .. } | ResolveIntoPackage::MainField { .. }
            )
        });
    }
    if let Some(mut extensions) = webpack_resolve_options.extensions {
        if let Some(pos) = extensions.iter().position(|ext| ext == "...") {
            extensions.splice(pos..=pos, take(&mut resolve_options.extensions));
        }
        resolve_options.extensions = extensions;
    }
    if let Some(main_fields) = webpack_resolve_options.main_fields {
        let mut old = resolve_options
            .into_package
            .extract_if(0.., |field| {
                matches!(field, ResolveIntoPackage::MainField { .. })
            })
            .collect::<Vec<_>>();
        for field in main_fields {
            if &*field == "..." {
                resolve_options.into_package.extend(take(&mut old));
            } else {
                resolve_options
                    .into_package
                    .push(ResolveIntoPackage::MainField { field });
            }
        }
    }
    if webpack_resolve_options.no_exports_field {
        resolve_options
            .into_package
            .retain(|field| !matches!(field, ResolveIntoPackage::ExportsField { .. }));
    }
    if let Some(main_files) = webpack_resolve_options.main_files {
        resolve_options.default_files = main_files;
    }
    if webpack_resolve_options.no_modules {
        resolve_options.modules.clear();
    }
    if webpack_resolve_options.prefer_relative {
        resolve_options.prefer_relative = true;
    }
    Ok(resolve_options.cell())
}

/// An issue that occurred while evaluating node code.
#[turbo_tasks::value(shared)]
pub struct BuildDependencyIssue {
    pub path: FileSystemPath,
    pub source: IssueSource,
}

#[async_trait]
#[turbo_tasks::value_impl]
impl Issue for BuildDependencyIssue {
    fn severity(&self) -> IssueSeverity {
        IssueSeverity::Warning
    }

    async fn title(&self) -> Result<StyledString> {
        Ok(StyledString::Text(rcstr!(
            "Build dependencies are not yet supported"
        )))
    }

    fn stage(&self) -> IssueStage {
        IssueStage::Unsupported
    }

    async fn file_path(&self) -> Result<FileSystemPath> {
        self.source.file_path().owned().await
    }

    async fn description(&self) -> Result<Option<StyledString>> {
        Ok(Some(StyledString::Line(vec![
            StyledString::Text(rcstr!("The file at ")),
            StyledString::Code(self.path.to_string().into()),
            StyledString::Text(
                " is a build dependency, which is not yet implemented.
    Changing this file or any dependency will not be recognized and might require restarting the \
                 server"
                    .into(),
            ),
        ])))
    }

    fn source(&self) -> Option<IssueSource> {
        Some(self.source)
    }
}

#[turbo_tasks::value(shared)]
pub struct EvaluateEmittedErrorIssue {
    pub source: IssueSource,
    pub severity: IssueSeverity,
    pub error: StructuredError,
    pub assets_for_source_mapping: ResolvedVc<AssetsForSourceMapping>,
    pub assets_root: FileSystemPath,
    pub project_dir: FileSystemPath,
}

#[async_trait]
#[turbo_tasks::value_impl]
impl Issue for EvaluateEmittedErrorIssue {
    async fn file_path(&self) -> Result<FileSystemPath> {
        self.source.file_path().owned().await
    }

    fn stage(&self) -> IssueStage {
        IssueStage::Transform
    }

    fn severity(&self) -> IssueSeverity {
        self.severity
    }

    async fn title(&self) -> Result<StyledString> {
        Ok(StyledString::Text(rcstr!("Issue while running loader")))
    }

    async fn description(&self) -> Result<Option<StyledString>> {
        Ok(Some(StyledString::Text(
            self.error
                .print(
                    *self.assets_for_source_mapping,
                    self.assets_root.clone(),
                    self.project_dir.clone(),
                    FormattingMode::Plain,
                )
                .await?
                .into(),
        )))
    }

    fn source(&self) -> Option<IssueSource> {
        Some(self.source)
    }
}

#[turbo_tasks::value(shared)]
pub struct EvaluateErrorLoggingIssue {
    pub source: IssueSource,
    pub severity: IssueSeverity,
    #[turbo_tasks(trace_ignore)]
    pub logging: Vec<LogInfo>,
    pub assets_for_source_mapping: ResolvedVc<AssetsForSourceMapping>,
    pub assets_root: FileSystemPath,
    pub project_dir: FileSystemPath,
}

#[async_trait]
#[turbo_tasks::value_impl]
impl Issue for EvaluateErrorLoggingIssue {
    async fn file_path(&self) -> Result<FileSystemPath> {
        self.source.file_path().owned().await
    }

    fn stage(&self) -> IssueStage {
        IssueStage::Transform
    }

    fn severity(&self) -> IssueSeverity {
        self.severity
    }

    async fn title(&self) -> Result<StyledString> {
        Ok(StyledString::Text(rcstr!(
            "Error logging while running loader"
        )))
    }

    async fn description(&self) -> Result<Option<StyledString>> {
        fn fmt_args(prefix: String, args: &[JsonValue]) -> String {
            let mut iter = args.iter();
            let Some(first) = iter.next() else {
                return "".to_string();
            };
            let mut result = prefix;
            if let JsonValue::String(s) = first {
                result.push_str(s);
            } else {
                result.push_str(&first.to_string());
            }
            for arg in iter {
                result.push(' ');
                result.push_str(&arg.to_string());
            }
            result
        }
        let lines = self
            .logging
            .iter()
            .map(|log| match log.log_type {
                LogType::Error => {
                    StyledString::Strong(fmt_args("<e> ".to_string(), &log.args).into())
                }
                LogType::Warn => StyledString::Text(fmt_args("<w> ".to_string(), &log.args).into()),
                LogType::Info => StyledString::Text(fmt_args("<i> ".to_string(), &log.args).into()),
                LogType::Log => StyledString::Text(fmt_args("<l> ".to_string(), &log.args).into()),
                LogType::Clear => StyledString::Strong(rcstr!("---")),
                _ => {
                    unimplemented!("{:?} is not implemented", log.log_type)
                }
            })
            .collect::<Vec<_>>();
        Ok(Some(StyledString::Stack(lines)))
    }

    fn source(&self) -> Option<IssueSource> {
        Some(self.source)
    }
}