refactor(tsc): remove TS program creation during snapshotting

cli/build.rs

@@ -13,48 +13,13 @@ mod ts {
   use std::path::PathBuf;
 
   use deno_core::op2;
+  use deno_core::v8;
   use deno_core::OpState;
   use deno_error::JsErrorBox;
   use serde::Serialize;
 
   use super::*;
 
-  #[derive(Debug, Serialize)]
-  #[serde(rename_all = "camelCase")]
-  struct BuildInfoResponse {
-    build_specifier: String,
-    libs: Vec<String>,
-  }
-
-  #[op2]
-  #[serde]
-  fn op_build_info(state: &mut OpState) -> BuildInfoResponse {
-    let build_specifier = "asset:///bootstrap.ts".to_string();
-    let build_libs = state
-      .borrow::<Vec<&str>>()
-      .iter()
-      .map(|s| s.to_string())
-      .collect();
-    BuildInfoResponse {
-      build_specifier,
-      libs: build_libs,
-    }
-  }
-
-  #[op2(fast)]
-  fn op_is_node_file() -> bool {
-    false
-  }
-
-  #[op2]
-  #[string]
-  fn op_script_version(
-    _state: &mut OpState,
-    #[string] _arg: &str,
-  ) -> Result<Option<String>, JsErrorBox> {
-    Ok(Some("1".to_string()))
-  }
-
   #[derive(Debug, Serialize)]
   #[serde(rename_all = "camelCase")]
   struct LoadResponse {
@@ -74,19 +39,10 @@ mod ts {
     let op_crate_libs = state.borrow::<HashMap<&str, PathBuf>>();
     let path_dts = state.borrow::<PathBuf>();
     let re_asset = lazy_regex::regex!(r"asset:/{3}lib\.(\S+)\.d\.ts");
-    let build_specifier = "asset:///bootstrap.ts";
-
-    // we need a basic file to send to tsc to warm it up.
-    if load_specifier == build_specifier {
-      Ok(LoadResponse {
-        data: r#"Deno.writeTextFile("hello.txt", "hello deno!");"#.to_string(),
-        version: "1".to_string(),
-        // this corresponds to `ts.ScriptKind.TypeScript`
-        script_kind: 3,
-      })
-      // specifiers come across as `asset:///lib.{lib_name}.d.ts` and we need to
-      // parse out just the name so we can lookup the asset.
-    } else if let Some(caps) = re_asset.captures(load_specifier) {
+
+    // specifiers come across as `asset:///lib.{lib_name}.d.ts` and we need to
+    // parse out just the name so we can lookup the asset.
+    if let Some(caps) = re_asset.captures(load_specifier) {
       if let Some(lib) = caps.get(1).map(|m| m.as_str()) {
         // if it comes from an op crate, we were supplied with the path to the
         // file.
@@ -100,28 +56,25 @@ mod ts {
         };
         let data =
           std::fs::read_to_string(path).map_err(JsErrorBox::from_err)?;
-        Ok(LoadResponse {
+        return Ok(LoadResponse {
           data,
           version: "1".to_string(),
           // this corresponds to `ts.ScriptKind.TypeScript`
           script_kind: 3,
-        })
-      } else {
-        Err(JsErrorBox::new(
-          "InvalidSpecifier",
-          format!("An invalid specifier was requested: {}", load_specifier),
-        ))
+        });
       }
-    } else {
-      Err(JsErrorBox::new(
-        "InvalidSpecifier",
-        format!("An invalid specifier was requested: {}", load_specifier),
-      ))
     }
+
+    Err(JsErrorBox::new(
+      "InvalidSpecifier",
+      format!("An invalid specifier was requested: {}", load_specifier),
+    ))
   }
 
   deno_core::extension!(deno_tsc,
-    ops = [op_build_info, op_is_node_file, op_load, op_script_version],
+    ops = [
+      op_load,
+    ],
     esm_entry_point = "ext:deno_tsc/99_main_compiler.js",
     esm = [
       dir "tsc",
@@ -277,6 +230,28 @@ mod ts {
     )
     .unwrap();
 
+    // Leak to satisfy type-checker. It's okay since it's only run once for a build script.
+    let build_libs_ = Box::leak(Box::new(build_libs.clone()));
+    let runtime_cb = Box::new(|rt: &mut deno_core::JsRuntimeForSnapshot| {
+      let scope = &mut rt.handle_scope();
+
+      let context = scope.get_current_context();
+      let global = context.global(scope);
+
+      let name = v8::String::new(scope, "snapshot").unwrap();
+      let snapshot_fn_val = global.get(scope, name.into()).unwrap();
+      let snapshot_fn: v8::Local<v8::Function> =
+        snapshot_fn_val.try_into().unwrap();
+      let undefined = v8::undefined(scope);
+      let build_libs = build_libs_.clone();
+      let build_libs_v8 =
+        deno_core::serde_v8::to_v8(scope, build_libs).unwrap();
+
+      snapshot_fn
+        .call(scope, undefined.into(), &[build_libs_v8])
+        .unwrap();
+    });
+
     let output = create_snapshot(
       CreateSnapshotOptions {
         cargo_manifest_dir: env!("CARGO_MANIFEST_DIR"),
@@ -287,7 +262,7 @@ mod ts {
           path_dts,
         )],
         extension_transpiler: None,
-        with_runtime_cb: None,
+        with_runtime_cb: Some(runtime_cb),
         skip_op_registration: false,
       },
       None,

cli/tsc/99_main_compiler.js

@@ -22,7 +22,6 @@ import {
   getAssets,
   host,
   setLogDebug,
-  SOURCE_FILE_CACHE,
 } from "./97_ts_host.js";
 import { serverMainLoop } from "./98_lsp.js";
 
@@ -39,16 +38,6 @@ const ops = core.ops;
 /** @type {Map<string, string>} */
 const normalizedToOriginalMap = new Map();
 
-const SNAPSHOT_COMPILE_OPTIONS = {
-  esModuleInterop: true,
-  jsx: ts.JsxEmit.React,
-  module: ts.ModuleKind.ESNext,
-  noEmit: true,
-  strict: true,
-  target: ts.ScriptTarget.ESNext,
-  lib: ["lib.deno.window.d.ts"],
-};
-
 /** @type {Array<[string, number]>} */
 const stats = [];
 let statsStart = 0;
@@ -225,44 +214,26 @@ function exec({ config, debug: debugFlag, rootNames, localOnly }) {
   debug("<<< exec stop");
 }
 
-// A build time only op that provides some setup information that is used to
-// ensure the snapshot is setup properly.
-/** @type {{ buildSpecifier: string; libs: string[]; nodeBuiltInModuleNames: string[] }} */
-const { buildSpecifier, libs } = ops.op_build_info();
-
-for (const lib of libs) {
-  const specifier = `lib.${lib}.d.ts`;
-  // we are using internal APIs here to "inject" our custom libraries into
-  // tsc, so things like `"lib": [ "deno.ns" ]` are supported.
-  if (!ts.libs.includes(lib)) {
-    ts.libs.push(lib);
-    ts.libMap.set(lib, `lib.${lib}.d.ts`);
+globalThis.snapshot = function (libs) {
+  for (const lib of libs) {
+    const specifier = `lib.${lib}.d.ts`;
+    // we are using internal APIs here to "inject" our custom libraries into
+    // tsc, so things like `"lib": [ "deno.ns" ]` are supported.
+    if (!ts.libs.includes(lib)) {
+      ts.libs.push(lib);
+      ts.libMap.set(lib, `lib.${lib}.d.ts`);
+    }
+    // we are caching in memory common type libraries that will be re-used by
+    // tsc on when the snapshot is restored
+    assert(
+      !!host.getSourceFile(
+        `${ASSETS_URL_PREFIX}${specifier}`,
+        ts.ScriptTarget.ESNext,
+      ),
+      `failed to load '${ASSETS_URL_PREFIX}${specifier}'`,
+    );
   }
-  // we are caching in memory common type libraries that will be re-used by
-  // tsc on when the snapshot is restored
-  assert(
-    !!host.getSourceFile(
-      `${ASSETS_URL_PREFIX}${specifier}`,
-      ts.ScriptTarget.ESNext,
-    ),
-    `failed to load '${ASSETS_URL_PREFIX}${specifier}'`,
-  );
-}
-// this helps ensure as much as possible is in memory that is re-usable
-// before the snapshotting is done, which helps unsure fast "startup" for
-// subsequent uses of tsc in Deno.
-const TS_SNAPSHOT_PROGRAM = ts.createProgram({
-  rootNames: [buildSpecifier],
-  options: SNAPSHOT_COMPILE_OPTIONS,
-  host,
-});
-assert(
-  ts.getPreEmitDiagnostics(TS_SNAPSHOT_PROGRAM).length === 0,
-  "lib.d.ts files have errors",
-);
-
-// remove this now that we don't need it anymore for warming up tsc
-SOURCE_FILE_CACHE.delete(buildSpecifier);
+};
 
 // exposes the functions that are called by `tsc::exec()` when type
 // checking TypeScript.