feat(es/codegen): Support sourceMap.url option of terser (#10346)

**Related issue:** - vercel/ncc#1258

Author: kdy1

.changeset/forty-tables-obey.md

@@ -0,0 +1,5 @@
+---
+swc_compiler_base: major
+---
+
+feat(es/codegen): Support `sourceMap.url` option of `terser`

crates/swc/src/config/mod.rs

@@ -767,7 +767,7 @@ impl Options {
  output: JscOutputConfig {
  charset,
  preamble,
- preserve_annotations: cfg.jsc.output.preserve_annotations,
+ ..cfg.jsc.output
  },
  emit_assert_for_import_attributes: experimental
  .emit_assert_for_import_attributes
@@ -1184,6 +1184,9 @@ pub struct JscOutputConfig {
 
  #[serde(default)]
  pub preserve_annotations: BoolConfig<false>,
+
+ #[serde(default)]
+ pub source_map_url: Option<String>,
 }
 
 #[derive(Debug, Clone, Serialize, Deserialize, Default)]

crates/swc/src/lib.rs

@@ -760,18 +760,18 @@ impl Compiler {
 
  let target = opts.ecma.clone().into();
 
- let (source_map, orig) = opts
+ let (source_map, orig, source_map_url) = opts
  .source_map
  .as_ref()
  .map(|obj| -> Result<_, Error> {
  let orig = obj.content.as_ref().map(|s| s.to_sourcemap()).transpose()?;
 
- Ok((SourceMapsConfig::Bool(true), orig))
+ Ok((SourceMapsConfig::Bool(true), orig, obj.url.as_deref()))
  })
  .unwrap_as_option(|v| {
  Some(Ok(match v {
- Some(true) => (SourceMapsConfig::Bool(true), None),
- _ => (SourceMapsConfig::Bool(false), None),
+ Some(true) => (SourceMapsConfig::Bool(true), None, None),
+ _ => (SourceMapsConfig::Bool(false), None, None),
  }))
  })
  .unwrap()?;
@@ -924,6 +924,7 @@ impl Compiler {
  .reduce_escaped_newline,
  ),
  output: None,
+ source_map_url,
  },
  );
 
@@ -1073,6 +1074,7 @@ impl Compiler {
  } else {
  Some(output)
  },
+ source_map_url: config.output.source_map_url.as_deref(),
  },
  )
  })

crates/swc/tests/fixture/issues-10xxx/10346/input/.swcrc

@@ -0,0 +1,8 @@
+{
+ "sourceMaps": true,
+ "jsc": {
+ "output": {
+ "sourceMapUrl": "input.js.map"
+ }
+ }
+}

crates/swc/tests/fixture/issues-10xxx/10346/input/input.js

@@ -0,0 +1,2 @@
+
+export const foo = 1;

crates/swc/tests/fixture/issues-10xxx/10346/output/input.js

@@ -0,0 +1,13 @@
+{
+ "mappings": "AACA,OAAO,IAAMA,MAAM,EAAE",
+ "names": [
+ "foo"
+ ],
+ "sources": [
+ "../../input/input.js"
+ ],
+ "sourcesContent": [
+ "\nexport const foo = 1;"
+ ],
+ "version": 3
+}

crates/swc/tests/fixture/issues-10xxx/10346/output/input.map

@@ -119,6 +119,7 @@ pub struct PrintArgs<'a> {
  pub preamble: &'a str,
  pub codegen_config: swc_ecma_codegen::Config,
  pub output: Option<FxHashMap<String, String>>,
+ pub source_map_url: Option<&'a str>,
 }
 
 impl Default for PrintArgs<'_> {
@@ -138,6 +139,7 @@ impl Default for PrintArgs<'_> {
  preamble: "",
  codegen_config: Default::default(),
  output: None,
+ source_map_url: None,
  }
  }
 }
@@ -168,6 +170,7 @@ pub fn print<T>(
  preamble,
  codegen_config,
  output,
+ source_map_url,
  }: PrintArgs,
 ) -> Result<TransformOutput, Error>
 where
@@ -177,7 +180,7 @@ where
 
  let mut src_map_buf = Vec::new();
 
- let src = {
+ let mut src = {
  let mut buf = std::vec::Vec::new();
  {
  let mut w = swc_ecma_codegen::text_writer::JsWriter::new(
@@ -251,13 +254,18 @@ where
  .to_writer(&mut buf)
  .context("failed to write source map")?;
  let map = String::from_utf8(buf).context("source map is not utf-8")?;
+
+ if let Some(source_map_url) = source_map_url {
+ src.push_str("\n//# sourceMappingURL=");
+ src.push_str(source_map_url);
+ }
+
  (src, Some(map))
  } else {
  (src, None)
  }
  }
  SourceMapsConfig::Str(_) => {
- let mut src = src;
  let mut buf = std::vec::Vec::new();
 
  map.unwrap()