refactor: don't use anyhow (#269)

Cargo.toml

@@ -23,15 +23,14 @@ react = ["transforms", "swc_ecma_transforms_react", "swc_ecma_transforms_macros"
 scopes = ["view", "utils", "visit"]
 sourcemap = ["dprint-swc-ext/sourcemap"]
 transforms = ["swc_ecma_loader", "swc_ecma_transforms_base"]
-emit = ["anyhow", "base64", "codegen", "sourcemap"]
+emit = ["base64", "codegen", "sourcemap", "dep:sourcemap"]
 transpiling = ["emit", "proposal", "react", "transforms", "typescript", "utils", "visit"]
 typescript = ["transforms", "swc_ecma_transforms_typescript"]
 utils = ["swc_ecma_utils"]
 view = ["dprint-swc-ext/view"]
 visit = ["swc_ecma_visit", "swc_visit", "swc_visit_macros", "swc_macros_common"]
 
 [dependencies]
-anyhow = { version = "1.0.64", optional = true }
 base64 = { version = "0.21.6", optional = true }
 deno_media_type = "0.1.4"
 deno_terminal = "0.1.1"
@@ -75,6 +74,8 @@ swc_macros_common = { version = "=0.3.13", optional = true }
 swc_trace_macro = { version = "=0.1.3", optional = true }
 swc_visit = { version = "=0.6.1", optional = true }
 swc_visit_macros = { version = "=0.5.13", optional = true }
+# just for error handling
+sourcemap = { version = "9.0.0", optional = true }
 thiserror = "1.0.58"
 
 [dev-dependencies]

src/emit.rs

@@ -2,7 +2,6 @@
 
 use std::string::FromUtf8Error;
 
-use anyhow::Result;
 use base64::Engine;
 use thiserror::Error;
 
@@ -83,9 +82,11 @@ pub struct EmittedSourceText {
 #[derive(Debug, Error)]
 pub enum EmitError {
   #[error(transparent)]
-  SwcEmit(anyhow::Error),
+  SwcEmit(std::io::Error),
   #[error(transparent)]
-  SourceMap(anyhow::Error),
+  SourceMap(sourcemap::Error),
+  #[error(transparent)]
+  SourceMapEncode(base64::EncodeSliceError),
 }
 
 /// Emits the program as a string of JavaScript code, possibly with the passed
@@ -120,7 +121,7 @@ pub fn emit(
     };
     program
       .emit_with(&mut emitter)
-      .map_err(|e| EmitError::SwcEmit(e.into()))?;
+      .map_err(EmitError::SwcEmit)?;
   }
 
   let mut map: Option<Vec<u8>> = None;
@@ -141,14 +142,14 @@ pub fn emit(
     }
     source_map
       .to_writer(&mut map_buf)
-      .map_err(|e| EmitError::SourceMap(e.into()))?;
+      .map_err(EmitError::SourceMap)?;
 
     if emit_options.source_map == SourceMapOption::Inline {
       // length is from the base64 crate examples
       let mut inline_buf = vec![0; map_buf.len() * 4 / 3 + 4];
       let size = base64::prelude::BASE64_STANDARD
         .encode_slice(map_buf, &mut inline_buf)
-        .map_err(|err| EmitError::SourceMap(err.into()))?;
+        .map_err(EmitError::SourceMapEncode)?;
       let inline_buf = &inline_buf[..size];
       let prelude_text = "//# sourceMappingURL=data:application/json;base64,";
       let src_has_trailing_newline = src_buf.ends_with(&[b'\n']);

src/transpiling/mod.rs

@@ -4,7 +4,6 @@ use std::borrow::Cow;
 use std::rc::Rc;
 use std::sync::Arc;
 
-use anyhow::Result;
 use deno_media_type::MediaType;
 use swc_ecma_visit::as_folder;
 use thiserror::Error;