feat: add footer output option (#693)

Co-authored-by: underfin <likui.underfin@gmail.com>

crates/rolldown/src/chunk/mod.rs

@@ -157,6 +157,8 @@ impl Chunk {
         },
       )?;
     let rendered_chunk = self.get_rendered_chunk_info(graph, output_options, rendered_modules);
+
+    // TODO avoid rendered_chunk clone
     // add banner
     if let Some(banner_txt) = output_options.banner.call(rendered_chunk.clone()).await? {
       concat_source.add_prepend_source(Box::new(RawSource::new(banner_txt)));
@@ -166,6 +168,11 @@ impl Chunk {
       concat_source.add_source(Box::new(RawSource::new(exports)));
     }
 
+    // add footer
+    if let Some(footer_txt) = output_options.footer.call(rendered_chunk.clone()).await? {
+      concat_source.add_source(Box::new(RawSource::new(footer_txt)));
+    }
+
     let (content, map) = concat_source.content_and_sourcemap();
 
     Ok(ChunkRenderReturn { code: content, map, rendered_chunk })

crates/rolldown/src/lib.rs

@@ -28,7 +28,7 @@ pub use crate::{
     input_options::{resolve_options::ResolveOptions, External, InputOptions},
     output_options::{OutputFormat, OutputOptions, SourceMapType},
     types::input_item::InputItem,
-    types::output_option::Banner,
+    types::output_option::AddonOutputOption,
   },
   types::rolldown_output::RolldownOutput,
 };

crates/rolldown/src/options/normalized_output_options/mod.rs

@@ -1,5 +1,5 @@
 use super::output_options::SourceMapType;
-use crate::Banner;
+use crate::AddonOutputOption;
 use crate::{FileNameTemplate, OutputFormat};
 use derivative::Derivative;
 
@@ -11,5 +11,6 @@ pub struct NormalizedOutputOptions {
   pub dir: String,
   pub format: OutputFormat,
   pub sourcemap: SourceMapType,
-  pub banner: Banner,
+  pub banner: AddonOutputOption,
+  pub footer: AddonOutputOption,
 }

crates/rolldown/src/options/output_options/mod.rs

@@ -1,4 +1,4 @@
-use crate::Banner;
+use crate::AddonOutputOption;
 use derivative::Derivative;
 
 #[derive(Debug)]
@@ -39,7 +39,8 @@ pub struct OutputOptions {
   pub dir: Option<String>,
   pub format: Option<OutputFormat>,
   pub sourcemap: Option<SourceMapType>,
-  pub banner: Option<Banner>,
+  pub banner: Option<AddonOutputOption>,
+  pub footer: Option<AddonOutputOption>,
 }
 
 // impl Default for OutputOptions {

crates/rolldown/src/options/types/output_option.rs

@@ -4,33 +4,33 @@ use rolldown_error::BuildError;
 use std::fmt::Debug;
 use std::pin::Pin;
 
-pub type BannerFn = dyn Fn(
+pub type AddonFunction = dyn Fn(
     RenderedChunk,
   ) -> Pin<Box<(dyn Future<Output = Result<Option<String>, BuildError>> + Send + 'static)>>
   + Send
   + Sync;
 
-pub enum Banner {
+pub enum AddonOutputOption {
   String(Option<String>),
-  Fn(Box<BannerFn>),
+  Fn(Box<AddonFunction>),
 }
 
-impl Debug for Banner {
+impl Debug for AddonOutputOption {
   fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
     match self {
-      Self::String(value) => write!(f, "Banner::String({value:?})"),
-      Self::Fn(_) => write!(f, "Banner::Fn(...)"),
+      Self::String(value) => write!(f, "AddonFunction::String({value:?})"),
+      Self::Fn(_) => write!(f, "AddonFunction::Fn(...)"),
     }
   }
 }
 
-impl Default for Banner {
+impl Default for AddonOutputOption {
   fn default() -> Self {
     Self::String(None)
   }
 }
 
-impl Banner {
+impl AddonOutputOption {
   pub async fn call(&self, chunk: RenderedChunk) -> Result<Option<String>, BuildError> {
     match self {
       Self::String(value) => Ok(value.clone()),

crates/rolldown/src/utils/normalize_options.rs

@@ -72,13 +72,14 @@ pub fn normalize_options(
 
   // Normalize output options
 
-  let output_options = NormalizedOutputOptions {
+  let output_options: NormalizedOutputOptions = NormalizedOutputOptions {
     entry_file_names: raw_output.entry_file_names.unwrap_or_else(|| "[name].js".to_string()).into(),
     chunk_file_names: raw_output
       .chunk_file_names
       .unwrap_or_else(|| "[name]-[hash].js".to_string())
       .into(),
     banner: raw_output.banner.unwrap_or_default(),
+    footer: raw_output.footer.unwrap_or_default(),
     dir: raw_output.dir.unwrap_or_else(|| "dist".to_string()),
     format: raw_output.format.unwrap_or(crate::OutputFormat::Esm),
     sourcemap: raw_output.sourcemap.unwrap_or(SourceMapType::Hidden),

crates/rolldown_binding/src/options/binding_output_options/mod.rs

@@ -5,6 +5,8 @@ use derivative::Derivative;
 use napi_derive::napi;
 use serde::Deserialize;
 
+pub type AddonOutputOption = MaybeAsyncJsCallback<RenderedChunk, Option<String>>;
+
 #[napi(object, object_to_js = false)]
 #[derive(Deserialize, Derivative)]
 #[serde(rename_all = "camelCase")]
@@ -23,7 +25,7 @@ pub struct BindingOutputOptions {
   #[napi(
     ts_type = "Nullable<string> | ((chunk: RenderedChunk) => MaybePromise<VoidNullable<string>>)"
   )]
-  pub banner: Option<MaybeAsyncJsCallback<RenderedChunk, Option<String>>>,
+  pub banner: Option<AddonOutputOption>,
   // chunkFileNames: string | ((chunkInfo: PreRenderedChunk) => string);
   // compact: boolean;
   pub dir: Option<String>,
@@ -34,6 +36,12 @@ pub struct BindingOutputOptions {
   // extend: boolean;
   // externalLiveBindings: boolean;
   // footer: () => string | Promise<string>;
+  #[derivative(Debug = "ignore")]
+  #[serde(skip_deserializing)]
+  #[napi(
+    ts_type = "Nullable<string> | ((chunk: RenderedChunk) => MaybePromise<VoidNullable<string>>)"
+  )]
+  pub footer: Option<AddonOutputOption>,
   #[napi(ts_type = "'es' | 'cjs'")]
   pub format: Option<String>,
   // freeze: boolean;

crates/rolldown_binding/src/utils/normalize_binding_options.rs

@@ -4,7 +4,7 @@ use crate::{
   options::plugin::JsPlugin,
   types::{binding_rendered_chunk::RenderedChunk, js_callback::MaybeAsyncJsCallbackExt},
 };
-use rolldown::{Banner, InputOptions, OutputOptions};
+use rolldown::{AddonOutputOption, InputOptions, OutputOptions};
 use rolldown_error::BuildError;
 use rolldown_plugin::BoxPlugin;
 
@@ -14,6 +14,19 @@ pub struct NormalizeBindingOptionsReturn {
   pub plugins: Vec<BoxPlugin>,
 }
 
+fn normalize_addon_option(
+  addon_option: Option<crate::options::AddonOutputOption>,
+) -> Option<AddonOutputOption> {
+  addon_option.map(move |value| {
+    AddonOutputOption::Fn(Box::new(move |chunk| {
+      let fn_js = value.clone();
+      Box::pin(async move {
+        fn_js.await_call(RenderedChunk::from(chunk)).await.map_err(BuildError::from)
+      })
+    }))
+  })
+}
+
 pub fn normalize_binding_options(
   input_options: crate::options::BindingInputOptions,
   output_options: crate::options::BindingOutputOptions,
@@ -50,14 +63,8 @@ pub fn normalize_binding_options(
     chunk_file_names: output_options.chunk_file_names,
     dir: output_options.dir,
     sourcemap: output_options.sourcemap.map(Into::into),
-    banner: output_options.banner.map(move |value| {
-      Banner::Fn(Box::new(move |chunk| {
-        let fn_js = value.clone();
-        Box::pin(async move {
-          fn_js.await_call(RenderedChunk::from(chunk)).await.map_err(BuildError::from)
-        })
-      }))
-    }),
+    banner: normalize_addon_option(output_options.banner),
+    footer: normalize_addon_option(output_options.footer),
     ..Default::default()
   };
 

packages/rolldown/src/binding.d.ts

@@ -83,6 +83,9 @@ export interface BindingOutputOptions {
     | ((chunk: RenderedChunk) => MaybePromise<VoidNullable<string>>)
   dir?: string
   exports?: 'default' | 'named' | 'none' | 'auto'
+  footer?:
+    | Nullable<string>
+    | ((chunk: RenderedChunk) => MaybePromise<VoidNullable<string>>)
   format?: 'es' | 'cjs'
   plugins: Array<BindingPluginOptions>
   sourcemap?: 'file' | 'inline' | 'hidden'

packages/rolldown/src/options/output-options.ts

@@ -8,6 +8,7 @@ export interface OutputOptions {
   exports?: RollupOutputOptions['exports']
   sourcemap?: RollupOutputOptions['sourcemap']
   banner?: RollupOutputOptions['banner']
+  footer?: RollupOutputOptions['footer']
 }
 
 function normalizeFormat(
@@ -40,7 +41,7 @@ function normalizeSourcemap(
   }
 }
 
-const getAddon = <T extends 'banner'>(
+const getAddon = <T extends 'banner' | 'footer'>(
   config: OutputOptions,
   name: T,
 ): BindingOutputOptions[T] => {
@@ -63,5 +64,6 @@ export function normalizeOutputOptions(
     sourcemap: normalizeSourcemap(sourcemap),
     plugins: [],
     banner: getAddon(opts, 'banner'),
+    footer: getAddon(opts, 'footer'),
   }
 }

packages/rolldown/tests/fixtures/output/footer/_config.ts

@@ -0,0 +1,29 @@
+import type {
+  RollupOptions,
+  RolldownOutput,
+  RolldownOutputChunk,
+} from '../../../../src'
+import { expect } from 'vitest'
+
+const footerTxt = '// footer test\n'
+const footer = () => Promise.resolve().then(() => footerTxt)
+
+const config: RollupOptions = {
+  external: [/external/, 'external-a'],
+  output: {
+    footer,
+  },
+}
+
+export default {
+  config,
+  afterTest: (output: RolldownOutput) => {
+    expect(
+      output.output
+        .filter(({ type }) => type === 'chunk')
+        .every((chunk) =>
+          (chunk as RolldownOutputChunk).code.endsWith(footerTxt),
+        ),
+    ).toBe(true)
+  },
+}

packages/rolldown/tests/fixtures/output/footer/main.js

@@ -0,0 +1,4 @@
+import external from 'external'
+import externalA from 'external-a'
+
+console.log(external, externalA)