Allow skipping postcss relative config resolving

crates/turbopack-cli/src/contexts.rs

@@ -23,7 +23,9 @@ use turbopack_ecmascript_plugins::transform::{
     styled_components::{StyledComponentsTransformConfig, StyledComponentsTransformer},
     styled_jsx::StyledJsxTransformer,
 };
-use turbopack_node::execution_context::ExecutionContext;
+use turbopack_node::{
+    execution_context::ExecutionContext, transforms::postcss::PostCssTransformOptions,
+};
 
 #[turbo_tasks::value(shared)]
 pub enum NodeEnv {
@@ -139,7 +141,7 @@ async fn get_client_module_options_context(
 
     let module_options_context = ModuleOptionsContext {
         enable_jsx,
-        enable_postcss_transform: Some(Default::default()),
+        enable_postcss_transform: Some(PostCssTransformOptions::default().cell()),
         enable_typescript_transform: Some(Default::default()),
         rules: vec![(
             foreign_code_context_condition().await?,

crates/turbopack-node/src/transforms/postcss.rs

@@ -1,7 +1,9 @@
 use anyhow::{bail, Context, Result};
 use indexmap::indexmap;
 use serde::{Deserialize, Serialize};
-use turbo_tasks::{Completion, Completions, TryFlatJoinIterExt, Value, Vc};
+use turbo_tasks::{
+    trace::TraceRawVcs, Completion, Completions, TaskInput, TryFlatJoinIterExt, Value, Vc,
+};
 use turbo_tasks_bytes::stream::SingleValue;
 use turbo_tasks_fs::{
     json::parse_json_with_source_context, File, FileContent, FileSystemEntryType, FileSystemPath,
@@ -16,7 +18,7 @@ use turbopack_core::{
         Issue, IssueDescriptionExt, IssueExt, IssueSeverity, OptionStyledString, StyledString,
     },
     reference_type::{EntryReferenceSubType, InnerAssets, ReferenceType},
-    resolve::{find_context_file, FindContextFileResult},
+    resolve::{find_context_file, options::ImportMapping, FindContextFileResult},
     source::Source,
     source_transform::SourceTransform,
     virtual_source::VirtualSource,
@@ -38,6 +40,23 @@ struct PostCssProcessingResult {
     assets: Option<Vec<EmittedAsset>>,
 }
 
+#[derive(
+    Default, Copy, Clone, PartialEq, Eq, Debug, TraceRawVcs, Serialize, Deserialize, TaskInput,
+)]
+pub enum PostCssConfigLocation {
+    #[default]
+    ProjectPath,
+    ProjectPathOrLocalPath,
+}
+
+#[turbo_tasks::value(shared)]
+#[derive(Clone, Default)]
+pub struct PostCssTransformOptions {
+    pub postcss_package: Option<Vc<ImportMapping>>,
+    pub config_location: PostCssConfigLocation,
+    pub placeholder_for_future_extensions: u8,
+}
+
 #[turbo_tasks::function]
 fn postcss_configs() -> Vc<Vec<String>> {
     Vc::cell(
@@ -70,6 +89,7 @@ fn postcss_configs() -> Vc<Vec<String>> {
 pub struct PostCssTransform {
     evaluate_context: Vc<Box<dyn AssetContext>>,
     execution_context: Vc<ExecutionContext>,
+    config_location: PostCssConfigLocation,
 }
 
 #[turbo_tasks::value_impl]
@@ -78,10 +98,12 @@ impl PostCssTransform {
     pub fn new(
         evaluate_context: Vc<Box<dyn AssetContext>>,
         execution_context: Vc<ExecutionContext>,
+        config_location: PostCssConfigLocation,
     ) -> Vc<Self> {
         PostCssTransform {
             evaluate_context,
             execution_context,
+            config_location,
         }
         .cell()
     }
@@ -95,6 +117,7 @@ impl SourceTransform for PostCssTransform {
             PostCssTransformedAsset {
                 evaluate_context: self.evaluate_context,
                 execution_context: self.execution_context,
+                config_location: self.config_location,
                 source,
             }
             .cell(),
@@ -106,6 +129,7 @@ impl SourceTransform for PostCssTransform {
 struct PostCssTransformedAsset {
     evaluate_context: Vc<Box<dyn AssetContext>>,
     execution_context: Vc<ExecutionContext>,
+    config_location: PostCssConfigLocation,
     source: Vc<Box<dyn Source>>,
 }
 
@@ -196,6 +220,28 @@ async fn postcss_executor(
     ))
 }
 
+async fn find_config_in_location(
+    project_path: Vc<FileSystemPath>,
+    location: PostCssConfigLocation,
+    source: Vc<Box<dyn Source>>,
+) -> Result<Option<Vc<FileSystemPath>>> {
+    if let FindContextFileResult::Found(config_path, _) =
+        *find_context_file(project_path, postcss_configs()).await?
+    {
+        return Ok(Some(config_path));
+    }
+
+    if matches!(location, PostCssConfigLocation::ProjectPathOrLocalPath) {
+        if let FindContextFileResult::Found(config_path, _) =
+            *find_context_file(source.ident().path().parent(), postcss_configs()).await?
+        {
+            return Ok(Some(config_path));
+        }
+    }
+
+    Ok(None)
+}
+
 #[turbo_tasks::value_impl]
 impl PostCssTransformedAsset {
     #[turbo_tasks::function]
@@ -218,31 +264,23 @@ impl PostCssTransformedAsset {
         //     - pkg1/(postcss.config.js) // The actual config we're looking for
         //
         // We look for the config in the project path first, then the source path
-        let config_path = match *find_context_file(project_path, postcss_configs()).await? {
-            FindContextFileResult::Found(config_path, _) => config_path,
-            _ => {
-                let FindContextFileResult::Found(config_path, _) =
-                    *find_context_file(this.source.ident().path().parent(), postcss_configs())
-                        .await?
-                else {
-                    PostCssTransformIssue {
-                        source: this.source.ident().path(),
-                        title: "PostCSS transform skipped".to_string(),
-                        description: "Unable to find PostCSS config".to_string(),
-                        severity: IssueSeverity::Warning.cell(),
-                    }
-                    .cell()
-                    .emit();
-
-                    return Ok(ProcessPostCssResult {
-                        content: this.source.content(),
-                        assets: Vec::new(),
-                    }
-                    .cell());
-                };
+        let Some(config_path) =
+            find_config_in_location(project_path, this.config_location, this.source).await?
+        else {
+            PostCssTransformIssue {
+                source: this.source.ident().path(),
+                title: "PostCSS transform skipped".to_string(),
+                description: "Unable to find PostCSS config".to_string(),
+                severity: IssueSeverity::Warning.cell(),
+            }
+            .cell()
+            .emit();
 
-                config_path
+            return Ok(ProcessPostCssResult {
+                content: this.source.content(),
+                assets: Vec::new(),
             }
+            .cell());
         };
 
         let source_content = this.source.content();

crates/turbopack/src/module_options/mod.rs

@@ -397,6 +397,7 @@ impl ModuleOptions {
             ]);
         } else {
             if let Some(options) = enable_postcss_transform {
+                let options = options.await?;
                 let execution_context = execution_context
                     .context("execution_context is required for the postcss_transform")?;
 
@@ -417,6 +418,7 @@ impl ModuleOptions {
                                 "postcss".to_string(),
                             ),
                             execution_context,
+                            options.config_location,
                         )),
                     ]))],
                 ));

crates/turbopack/src/module_options/module_options_context.rs

@@ -4,18 +4,13 @@ use turbo_tasks::{trace::TraceRawVcs, ValueDefault, Vc};
 use turbopack_core::{environment::Environment, resolve::options::ImportMapping};
 use turbopack_ecmascript::{references::esm::UrlRewriteBehavior, TransformPlugin, TreeShakingMode};
 use turbopack_node::{
-    execution_context::ExecutionContext, transforms::webpack::WebpackLoaderItems,
+    execution_context::ExecutionContext,
+    transforms::{postcss::PostCssTransformOptions, webpack::WebpackLoaderItems},
 };
 
 use super::ModuleRule;
 use crate::condition::ContextCondition;
 
-#[derive(Default, Clone, PartialEq, Eq, Debug, TraceRawVcs, Serialize, Deserialize)]
-pub struct PostCssTransformOptions {
-    pub postcss_package: Option<Vc<ImportMapping>>,
-    pub placeholder_for_future_extensions: (),
-}
-
 #[derive(Clone, PartialEq, Eq, Debug, TraceRawVcs, Serialize, Deserialize)]
 pub struct LoaderRuleItem {
     pub loaders: Vc<WebpackLoaderItems>,
@@ -139,7 +134,7 @@ impl MdxTransformModuleOptions {
 #[serde(default)]
 pub struct ModuleOptionsContext {
     pub enable_jsx: Option<Vc<JsxTransformOptions>>,
-    pub enable_postcss_transform: Option<PostCssTransformOptions>,
+    pub enable_postcss_transform: Option<Vc<PostCssTransformOptions>>,
     pub enable_webpack_loaders: Option<Vc<WebpackLoadersOptions>>,
     pub enable_types: bool,
     pub enable_typescript_transform: Option<Vc<TypescriptTransformOptions>>,