[Rebased] Remove automatic core-js polyfills (vercel#91)

Rebase of #68, which was merged into a now-closed PR.

Closes #65.

When configured to use preset-env, this stops turbopack from inserting
dependencies on core-js. It's:

* Buggy/error-prone, at least through swc preset-env: 
  * vercel/the-three-body#65
* setImmediate "polyfills" always inserted for this nonstandard feature
when
    React (scheduler, iirc) does feature detection of it
* Big. Updating the snapshot alone for a test that only used [].includes
  resulted in a diff with nearly 4700 line deletions
* Not done by Next.js for modern targets in the past couple of years:
https://twitter.com/timneutkens/status/1234548900272517120

Test Plan: Added [].includes to preset_env snapshot test and verified no
references to core-js are inserted.

crates/next-dev/benches/bundlers/turbopack.rs

@@ -50,9 +50,8 @@ impl Bundler for Turbopack {
                 NpmPackage::new("react-refresh", "^0.12.0"),
                 NpmPackage::new("next", "^12.3.1"),
                 NpmPackage::new("@next/react-refresh-utils", "^12.3.1"),
-                // Dependencies on these are inserted by swc's preset_env
+                // Dependency on this is inserted by swc's preset_env
                 NpmPackage::new("@swc/helpers", "^0.4.11"),
-                NpmPackage::new("core-js", "^3.25.3"),
             ],
         )
         .context("failed to install from npm")?;

crates/turbopack-ecmascript/src/transform/mod.rs

@@ -6,7 +6,7 @@ use swc_core::{
     common::{chain, util::take::Take, FileName, Mark, SourceMap},
     ecma::{
         ast::{Module, ModuleItem, Program},
-        preset_env::{self, Mode, Targets},
+        preset_env::{self, Targets},
         transforms::{
             base::{feature::FeatureFlag, helpers::inject_helpers, Assumptions},
             react::react,
@@ -89,9 +89,10 @@ impl EcmascriptInputTransform {
             }
             EcmascriptInputTransform::PresetEnv(env) => {
                 let versions = env.runtime_versions().await?;
+                println!("versions {:?}", versions);
                 let config = swc_core::ecma::preset_env::Config {
                     targets: Some(Targets::Versions(*versions)),
-                    mode: Some(Mode::Usage),
+                    mode: None, // Don't insert core-js polyfills
                     ..Default::default()
                 };
 

crates/turbopack/tests/snapshot/integration/preset_env/input/index.js

@@ -1,3 +1,3 @@
 class Foo {}
 
-console.log(Foo);
+console.log(Foo, [].includes("foo"));

crates/turbopack/tests/snapshot/integration/preset_env/output/3f8b2_@swc_helpers_src__class_call_check.mjs.js.8bcaf458ac88e308.map

@@ -0,0 +1,6 @@
+{
+  "version": 3,
+  "sections": [
+    {"offset": {"line": 4, "column": 0}, "map": {"version":3,"sources":["/[project]/node_modules/.pnpm/@[email protected]/node_modules/@swc/helpers/src/_class_call_check.mjs"],"sourcesContent":["export default function _classCallCheck(instance, Constructor) {\n  if (!(instance instanceof Constructor)) {\n    throw new TypeError(\"Cannot call a class as a function\");\n  }\n}"],"names":[],"mappings":"AAAA;;;AAAe,SAAS,gBAAgB,QAAQ,EAAE,WAAW,EAAE;IAC7D,IAAI,CAAC,CAAC,oBAAoB,WAAW,GAAG;QACtC,MAAM,IAAI,UAAU,qCAAqC;IAC3D,CAAC;AACH"}},
+    {"offset": {"line": 12, "column": 0}, "map": {"version": 3, "names": [], "sources": [], "mappings": "A"}}]
+}

crates/turbopack/tests/snapshot/integration/preset_env/output/3f8b2_@swc_helpers_src__class_call_check.mjs.js.8c683f.map

@@ -0,0 +1,6 @@
+{
+  "version": 3,
+  "sections": [
+    {"offset": {"line": 2, "column": 0}, "map": {"version":3,"sources":["/[project]/node_modules/.pnpm/@[email protected]/node_modules/@swc/helpers/src/_class_call_check.mjs"],"sourcesContent":["export default function _classCallCheck(instance, Constructor) {\n  if (!(instance instanceof Constructor)) {\n    throw new TypeError(\"Cannot call a class as a function\");\n  }\n}"],"names":[],"mappings":"AAAA;;;AAAe,SAAS,gBAAgB,QAAQ,EAAE,WAAW,EAAE;IAC7D,IAAI,CAAC,CAAC,oBAAoB,WAAW,GAAG;QACtC,MAAM,IAAI,UAAU,qCAAqC;IAC3D,CAAC;AACH"}},
+    {"offset": {"line": 10, "column": 0}, "map": {"version": 3, "names": [], "sources": [], "mappings": "A"}}]
+}

crates/turbopack/tests/snapshot/integration/preset_env/output/crates_turbopack_tests_snapshot_integration_preset_env_input_index_17d7e7.js.b2643f4016b9579d.map → crates/turbopack/tests/snapshot/integration/preset_env/output/crates_turbopack_tests_snapshot_integration_preset_env_input_index_56c340.js.496f26fdbe25baf2.map

@@ -1,6 +1,6 @@
 {
   "version": 3,
   "sections": [
-    {"offset": {"line": 4, "column": 0}, "map": {"version":3,"sources":["/[project]/crates/turbopack/tests/snapshot/integration/preset_env/input/index.js"],"sourcesContent":["class Foo {}\n\nconsole.log(Foo);\n"],"names":[],"mappings":"AAAA;;;AAAA,IAAA,AAAM,MAAN,SAAM;;2IAAA;;AAEN,QAAQ,GAAG,CAAC"}},
+    {"offset": {"line": 4, "column": 0}, "map": {"version":3,"sources":["/[project]/crates/turbopack/tests/snapshot/integration/preset_env/input/index.js"],"sourcesContent":["class Foo {}\n\nconsole.log(Foo, [].includes(\"foo\"));\n"],"names":[],"mappings":"AAAA;;;AAAA,IAAA,AAAM,MAAN,SAAM;;yMAAA;;AAEN,QAAQ,GAAG,CAAC,KAAK,EAAE,CAAC,QAAQ,CAAC"}},
     {"offset": {"line": 12, "column": 0}, "map": {"version": 3, "names": [], "sources": [], "mappings": "A"}}]
 }

crates/turbopack/tests/snapshot/integration/preset_env/output/crates_turbopack_tests_snapshot_integration_preset_env_input_index_17d7e7.js.42272d.map → crates/turbopack/tests/snapshot/integration/preset_env/output/crates_turbopack_tests_snapshot_integration_preset_env_input_index_56c340.js.d5a489.map

@@ -1,6 +1,6 @@
 {
   "version": 3,
   "sections": [
-    {"offset": {"line": 2, "column": 0}, "map": {"version":3,"sources":["/[project]/crates/turbopack/tests/snapshot/integration/preset_env/input/index.js"],"sourcesContent":["class Foo {}\n\nconsole.log(Foo);\n"],"names":[],"mappings":"AAAA;;;AAAA,IAAA,AAAM,MAAN,SAAM;;2IAAA;;AAEN,QAAQ,GAAG,CAAC"}},
+    {"offset": {"line": 2, "column": 0}, "map": {"version":3,"sources":["/[project]/crates/turbopack/tests/snapshot/integration/preset_env/input/index.js"],"sourcesContent":["class Foo {}\n\nconsole.log(Foo, [].includes(\"foo\"));\n"],"names":[],"mappings":"AAAA;;;AAAA,IAAA,AAAM,MAAN,SAAM;;yMAAA;;AAEN,QAAQ,GAAG,CAAC,KAAK,EAAE,CAAC,QAAQ,CAAC"}},
     {"offset": {"line": 10, "column": 0}, "map": {"version": 3, "names": [], "sources": [], "mappings": "A"}}]
 }