feat(common): Use range mappings for source maps

crates/swc_common/src/source_map.rs

@@ -141,6 +141,16 @@ impl Default for SourceMap {
  }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub struct SourceMapMapping {
+ /// The location of the first byte of the source code in the source file.
+ pub src: BytePos,
+ /// The locaiton of the first byte of the source code in the generated code.
+ pub dst: LineCol,
+
+ pub is_range: bool,
+}
+
 impl SourceMap {
  pub fn new(path_mapping: FilePathMapping) -> SourceMap {
  SourceMap {
@@ -1194,7 +1204,7 @@ impl SourceMap {
  ///
  #[cfg(feature = "sourcemap")]
  #[cfg_attr(docsrs, doc(cfg(feature = "sourcemap")))]
- pub fn build_source_map(&self, mappings: &[(BytePos, LineCol)]) -> sourcemap::SourceMap {
+ pub fn build_source_map(&self, mappings: &[SourceMapMapping]) -> sourcemap::SourceMap {
  self.build_source_map_from(mappings, None)
  }
 
@@ -1203,7 +1213,7 @@ impl SourceMap {
  #[cfg_attr(docsrs, doc(cfg(feature = "sourcemap")))]
  pub fn build_source_map_from(
  &self,
- mappings: &[(BytePos, LineCol)],
+ mappings: &[SourceMapMapping],
  orig: Option<&sourcemap::SourceMap>,
  ) -> sourcemap::SourceMap {
  self.build_source_map_with_config(mappings, orig, DefaultSourceMapGenConfig)
@@ -1214,7 +1224,7 @@ impl SourceMap {
  #[cfg_attr(docsrs, doc(cfg(feature = "sourcemap")))]
  pub fn build_source_map_with_config(
  &self,
- mappings: &[(BytePos, LineCol)],
+ mappings: &[SourceMapMapping],
  orig: Option<&sourcemap::SourceMap>,
  config: impl SourceMapGenConfig,
  ) -> sourcemap::SourceMap {
@@ -1242,31 +1252,27 @@ impl SourceMap {
  let mut ch_state = ByteToCharPosState::default();
  let mut line_state = ByteToCharPosState::default();
 
- for (pos, lc) in mappings.iter() {
- let pos = *pos;
-
- if pos.is_reserved_for_comments() {
+ for SourceMapMapping { src, dst, is_range } in mappings.iter().copied() {
+ if src.is_reserved_for_comments() {
  continue;
  }
 
- let lc = *lc;
-
  // If pos is same as a DUMMY_SP (eg BytePos(0)) and if line and col are 0;
  // ignore the mapping.
- if lc.line == 0 && lc.col == 0 && pos.is_dummy() {
+ if dst.line == 0 && dst.col == 0 && src.is_dummy() {
  continue;
  }
 
- if pos == BytePos(u32::MAX) {
- builder.add_raw(lc.line, lc.col, 0, 0, Some(src_id), None, false);
+ if src == BytePos(u32::MAX) {
+ builder.add_raw(dst.line, dst.col, 0, 0, Some(src_id), None, is_range);
  continue;
  }
 
  let f;
  let f = match cur_file {
- Some(ref f) if f.start_pos <= pos && pos < f.end_pos => f,
+ Some(ref f) if f.start_pos <= src && src < f.end_pos => f,
  _ => {
- f = self.lookup_source_file(pos);
+ f = self.lookup_source_file(src);
  if config.skip(&f.name) {
  continue;
  }
@@ -1292,27 +1298,27 @@ impl SourceMap {
 
  let emit_columns = config.emit_columns(&f.name);
 
- if !emit_columns && lc.line == prev_dst_line {
+ if !emit_columns && dst.line == prev_dst_line {
  continue;
  }
 
- let mut line = match f.lookup_line(pos) {
+ let mut line = match f.lookup_line(src) {
  Some(line) => line as u32,
  None => continue,
  };
 
  let linebpos = f.lines[line as usize];
  debug_assert!(
- pos >= linebpos,
+ src >= linebpos,
  "{}: bpos = {:?}; linebpos = {:?};",
  f.name,
- pos,
+ src,
  linebpos,
  );
 
  let linechpos =
  linebpos.to_u32() - self.calc_utf16_offset(f, linebpos, &mut line_state);
- let chpos = pos.to_u32() - self.calc_utf16_offset(f, pos, &mut ch_state);
+ let chpos = src.to_u32() - self.calc_utf16_offset(f, src, &mut ch_state);
 
  debug_assert!(
  chpos >= linechpos,
@@ -1349,11 +1355,19 @@ impl SourceMap {
  }
 
  let name_idx = name
- .or_else(|| config.name_for_bytepos(pos))
+ .or_else(|| config.name_for_bytepos(src))
  .map(|name| builder.add_name(name));
 
- builder.add_raw(lc.line, lc.col, line, col, Some(src_id), name_idx, false);
- prev_dst_line = lc.line;
+ builder.add_raw(
+ dst.line,
+ dst.col,
+ line,
+ col,
+ Some(src_id),
+ name_idx,
+ is_range,
+ );
+ prev_dst_line = dst.line;
  }
 
  builder.into_sourcemap()