feat: add type_strip (#325)

Author: dsherret

Cargo.lock

@@ -24,6 +24,7 @@ scopes = ["view", "utils", "visit"]
 sourcemap = ["dprint-swc-ext/sourcemap", "swc_sourcemap"]
 transforms = ["swc_ecma_loader", "swc_ecma_transforms_base"]
 emit = ["base64", "codegen", "sourcemap"]
+type_strip = [ "swc_ts_fast_strip" ]
 transpiling = ["emit", "proposal", "react", "transforms", "typescript", "utils", "visit"]
 typescript = ["transforms", "swc_ecma_transforms_typescript"]
 utils = ["swc_ecma_utils"]
@@ -74,6 +75,7 @@ swc_bundler = { version = "=32.0.0", optional = true }
 swc_graph_analyzer = { version = "=14.0.1", optional = true }
 swc_macros_common = { version = "=1.0.1", optional = true }
 swc_sourcemap = { version = "=9.3.4", optional = true }
+swc_ts_fast_strip = { version = "=33.0.0", optional = true }
 swc_trace_macro = { version = "=2.0.2", optional = true }
 swc_visit = { version = "=2.0.1", optional = true }
 thiserror = "2.0.12"

Cargo.toml

@@ -7,6 +7,7 @@ use std::fmt::Display;
 use std::fmt::Write as _;
 use std::path::PathBuf;
 
+use deno_error::JsError;
 use deno_terminal::colors;
 use unicode_width::UnicodeWidthStr;
 
@@ -16,6 +17,8 @@ use crate::SourceRange;
 use crate::SourceRanged;
 use crate::SourceTextInfo;
 
+use crate::swc::common::errors::Diagnostic as SwcDiagnostic;
+
 pub enum DiagnosticLevel {
   Error,
   Warning,
@@ -560,6 +563,112 @@ fn specifier_to_file_path(specifier: &ModuleSpecifier) -> Option<PathBuf> {
   }
 }
 
+pub(crate) type DiagnosticsCell = crate::swc::common::sync::Lrc<
+  crate::swc::common::sync::Lock<Vec<SwcDiagnostic>>,
+>;
+
+#[derive(Default, Clone)]
+pub(crate) struct DiagnosticCollector {
+  diagnostics: DiagnosticsCell,
+}
+
+impl DiagnosticCollector {
+  pub fn into_handler_and_cell(
+    self,
+  ) -> (crate::swc::common::errors::Handler, DiagnosticsCell) {
+    let cell = self.diagnostics.clone();
+    (
+      crate::swc::common::errors::Handler::with_emitter(
+        true,
+        false,
+        Box::new(self),
+      ),
+      cell,
+    )
+  }
+}
+
+impl crate::swc::common::errors::Emitter for DiagnosticCollector {
+  fn emit(
+    &mut self,
+    db: &mut crate::swc::common::errors::DiagnosticBuilder<'_>,
+  ) {
+    let mut diagnostics = self.diagnostics.lock();
+    diagnostics.push(db.take());
+  }
+}
+
+#[derive(Debug, JsError)]
+#[class(syntax)]
+pub struct SwcFoldDiagnosticsError(Vec<String>);
+
+impl std::error::Error for SwcFoldDiagnosticsError {}
+
+impl std::fmt::Display for SwcFoldDiagnosticsError {
+  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+    for (i, diagnostic) in self.0.iter().enumerate() {
+      if i > 0 {
+        write!(f, "\n\n")?;
+      }
+
+      write!(f, "{}", diagnostic)?
+    }
+
+    Ok(())
+  }
+}
+
+pub(crate) fn ensure_no_fatal_swc_diagnostics(
+  source_map: &swc_common::SourceMap,
+  diagnostics: impl Iterator<Item = SwcDiagnostic>,
+) -> Result<(), SwcFoldDiagnosticsError> {
+  let fatal_diagnostics = diagnostics
+    .filter(is_fatal_swc_diagnostic)
+    .collect::<Vec<_>>();
+  if !fatal_diagnostics.is_empty() {
+    Err(SwcFoldDiagnosticsError(
+      fatal_diagnostics
+        .iter()
+        .map(|d| format_swc_diagnostic(source_map, d))
+        .collect::<Vec<_>>(),
+    ))
+  } else {
+    Ok(())
+  }
+}
+
+fn is_fatal_swc_diagnostic(diagnostic: &SwcDiagnostic) -> bool {
+  use crate::swc::common::errors::Level;
+  match diagnostic.level {
+    Level::Bug
+    | Level::Cancelled
+    | Level::FailureNote
+    | Level::Fatal
+    | Level::PhaseFatal
+    | Level::Error => true,
+    Level::Help | Level::Note | Level::Warning => false,
+  }
+}
+
+fn format_swc_diagnostic(
+  source_map: &swc_common::SourceMap,
+  diagnostic: &SwcDiagnostic,
+) -> String {
+  if let Some(span) = &diagnostic.span.primary_span() {
+    let file_name = source_map.span_to_filename(*span);
+    let loc = source_map.lookup_char_pos(span.lo);
+    format!(
+      "{} at {}:{}:{}",
+      diagnostic.message(),
+      file_name,
+      loc.line,
+      loc.col_display + 1,
+    )
+  } else {
+    diagnostic.message()
+  }
+}
+
 #[cfg(test)]
 mod tests {
   use std::borrow::Cow;

src/diagnostics.rs

@@ -26,6 +26,8 @@ mod source_map;
 mod text_changes;
 #[cfg(feature = "transpiling")]
 mod transpiling;
+#[cfg(feature = "type_strip")]
+mod type_strip;
 mod types;
 
 #[cfg(feature = "view")]
@@ -50,6 +52,8 @@ pub use source_map::*;
 pub use text_changes::*;
 #[cfg(feature = "transpiling")]
 pub use transpiling::*;
+#[cfg(feature = "type_strip")]
+pub use type_strip::*;
 pub use types::*;
 
 pub type ModuleSpecifier = url::Url;

src/lib.rs

@@ -23,12 +23,12 @@ use crate::ParseDiagnosticsError;
 use crate::ParsedSource;
 use crate::ProgramRef;
 use crate::SourceMap;
+use crate::diagnostics::DiagnosticCollector;
+use crate::diagnostics::SwcFoldDiagnosticsError;
+use crate::diagnostics::ensure_no_fatal_swc_diagnostics;
 use crate::emit;
 use crate::swc::ast::Program;
 use crate::swc::common::comments::SingleThreadedComments;
-use crate::swc::common::errors::Diagnostic as SwcDiagnostic;
-use crate::swc::common::sync::Lock;
-use crate::swc::common::sync::Lrc;
 use crate::swc::ecma_visit::visit_mut_pass;
 use crate::swc::parser::error::SyntaxError;
 use crate::swc::transforms::fixer;
@@ -667,31 +667,6 @@ fn convert_script_module_to_swc_script(
   })
 }
 
-#[derive(Default, Clone)]
-struct DiagnosticCollector {
-  diagnostics: Lrc<Lock<Vec<SwcDiagnostic>>>,
-}
-
-impl DiagnosticCollector {
-  pub fn into_handler(self) -> crate::swc::common::errors::Handler {
-    crate::swc::common::errors::Handler::with_emitter(
-      true,
-      false,
-      Box::new(self),
-    )
-  }
-}
-
-impl crate::swc::common::errors::Emitter for DiagnosticCollector {
-  fn emit(
-    &mut self,
-    db: &mut crate::swc::common::errors::DiagnosticBuilder<'_>,
-  ) {
-    let mut diagnostics = self.diagnostics.lock();
-    diagnostics.push(db.take());
-  }
-}
-
 #[derive(Debug, Error, JsError)]
 pub enum FoldProgramError {
   #[class(inherit)]
@@ -849,91 +824,18 @@ pub fn fold_program<'a>(
   );
 
   let emitter = DiagnosticCollector::default();
-  let diagnostics_cell = emitter.diagnostics.clone();
-  let handler = emitter.into_handler();
+  let (handler, diagnostics_cell) = emitter.into_handler_and_cell();
   let result = crate::swc::common::errors::HANDLER.set(&handler, || {
     helpers::HELPERS
       .set(&helpers::Helpers::new(false), || program.apply(passes))
   });
 
   let mut diagnostics = diagnostics_cell.borrow_mut();
   let diagnostics = std::mem::take(&mut *diagnostics);
-  ensure_no_fatal_swc_diagnostics(source_map, diagnostics.into_iter())?;
+  ensure_no_fatal_swc_diagnostics(source_map.inner(), diagnostics.into_iter())?;
   Ok(result)
 }
 
-#[derive(Debug, JsError)]
-#[class(syntax)]
-pub struct SwcFoldDiagnosticsError(Vec<String>);
-
-impl std::error::Error for SwcFoldDiagnosticsError {}
-
-impl std::fmt::Display for SwcFoldDiagnosticsError {
-  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-    for (i, diagnostic) in self.0.iter().enumerate() {
-      if i > 0 {
-        write!(f, "\n\n")?;
-      }
-
-      write!(f, "{}", diagnostic)?
-    }
-
-    Ok(())
-  }
-}
-
-fn ensure_no_fatal_swc_diagnostics(
-  source_map: &SourceMap,
-  diagnostics: impl Iterator<Item = SwcDiagnostic>,
-) -> Result<(), SwcFoldDiagnosticsError> {
-  let fatal_diagnostics = diagnostics
-    .filter(is_fatal_swc_diagnostic)
-    .collect::<Vec<_>>();
-  if !fatal_diagnostics.is_empty() {
-    Err(SwcFoldDiagnosticsError(
-      fatal_diagnostics
-        .iter()
-        .map(|d| format_swc_diagnostic(source_map, d))
-        .collect::<Vec<_>>(),
-    ))
-  } else {
-    Ok(())
-  }
-}
-
-fn is_fatal_swc_diagnostic(diagnostic: &SwcDiagnostic) -> bool {
-  use crate::swc::common::errors::Level;
-  match diagnostic.level {
-    Level::Bug
-    | Level::Cancelled
-    | Level::FailureNote
-    | Level::Fatal
-    | Level::PhaseFatal
-    | Level::Error => true,
-    Level::Help | Level::Note | Level::Warning => false,
-  }
-}
-
-fn format_swc_diagnostic(
-  source_map: &SourceMap,
-  diagnostic: &SwcDiagnostic,
-) -> String {
-  if let Some(span) = &diagnostic.span.primary_span() {
-    let source_map = source_map.inner();
-    let file_name = source_map.span_to_filename(*span);
-    let loc = source_map.lookup_char_pos(span.lo);
-    format!(
-      "{} at {}:{}:{}",
-      diagnostic.message(),
-      file_name,
-      loc.line,
-      loc.col_display + 1,
-    )
-  } else {
-    diagnostic.message()
-  }
-}
-
 fn ensure_no_fatal_diagnostics<'a>(
   diagnostics: Box<dyn Iterator<Item = &'a ParseDiagnostic> + 'a>,
 ) -> Result<(), ParseDiagnosticsError> {