fix(code-runtime): separate model environment from native startup paths

packages/code-runtime/code-runtime-node/src/environment.ts

@@ -0,0 +1,4 @@
+/** Startup variables required by native executables before model evaluation. */
+
+/** Native executable search and Windows system paths retained in the OS environment. */
+export const STARTUP_ENVIRONMENT_NAMES: ReadonlySet<string> = new Set(['PATH', 'PATHEXT', 'SYSTEMROOT', 'WINDIR'])

packages/code-runtime/code-runtime-node/src/index.ts

@@ -18,6 +18,7 @@ import { bootstrapArgs } from './launch.ts'
 import type { LaunchConfig } from './launch.ts'
 import { OutputLedger } from './output-ledger.ts'
 import { drainOutput } from './output-stream.ts'
+import { STARTUP_ENVIRONMENT_NAMES } from './environment.ts'
 import { decodeCodeJsonWire, encodeCodeJsonWire } from './json-wire.ts'
 import type { ProgramBootData } from './protocol.ts'
 
@@ -43,7 +44,6 @@ type ResolvedConfig = Required<Omit<Config, 'bootstrapPath'>> & Pick<Config, 'bo
 interface LiveRun { controller: AbortController; finished: Promise<void> }
 const STRIP_PREFIX = 'async function __dsh_program__() {\n'
 const STRIP_SUFFIX = '\n}'
-const STARTUP_ENVIRONMENT = new Set(['PATH', 'PATHEXT', 'SYSTEMROOT', 'WINDIR'])
 
 function messageOf(error: unknown): string { return error instanceof Error ? error.message : String(error) }
 function record(value: unknown): value is Record<string, unknown> { return typeof value === 'object' && value !== null && !Array.isArray(value) }
@@ -213,9 +213,9 @@ export class NodeCodeRuntime extends CodeRuntime {
       const argv = [executable, `--max-old-space-size=${this.config.maxOldGenerationSizeMb}`, ...bootstrapArgs(this.ctx.fs, this.config, this.config.maxMessageBytes)]
       confined = policy.mode === 'danger-full-access' ? undefined : this.ctx.sandbox.confine(argv, { ...policy, mode: policy.mode })
       if (confined !== undefined) sandbox.enforcement = confined.enforcement
-      // Native launchers need executable search and Windows system paths until the child clears its environment.
+      // Native launchers need executable search and Windows system paths before the child installs its model environment.
       const env: NodeJS.ProcessEnv = Object.fromEntries(Object.keys(process.env)
-        .filter(key => !STARTUP_ENVIRONMENT.has(key.toUpperCase()))
+        .filter(key => !STARTUP_ENVIRONMENT_NAMES.has(key.toUpperCase()))
         .map(key => [key, undefined]))
       if ('pkg' in process && this.config.bootstrapPath === undefined) env.DSH_CODE_RUNTIME_NODE = '1'
       handle = this.ctx.subprocess.spawn({ argv: confined?.argv ?? argv, cwd: spec.cwd, env, stdio: { stdin: 'ignore', stdout: 'pipe', stderr: 'pipe', control: 'pipe' }, graceMs: this.config.graceMs, signal })

packages/code-runtime/code-runtime-node/src/process.ts

@@ -2,6 +2,7 @@
 import type { Duplex } from 'node:stream'
 import { JsonChannel } from './channel.ts'
 import { runProgram } from './bootstrap.ts'
+import { STARTUP_ENVIRONMENT_NAMES } from './environment.ts'
 import type { PatchableStream } from './bootstrap.ts'
 import type { ReplyMessage, ProgramBootData, ProgramToHost } from './protocol.ts'
 
@@ -22,7 +23,11 @@ export interface ProgramProcess {
  */
 export async function runNodeMain(stream: Duplex, maxMessageBytes: number, processState: ProgramProcess): Promise<void> {
   if (!Number.isSafeInteger(maxMessageBytes) || maxMessageBytes <= 0 || maxMessageBytes > 0xffff_ffff) throw new Error('invalid control message limit')
-  for (const key of Object.keys(processState.env)) Reflect.deleteProperty(processState.env, key)
+  for (const key of Object.keys(processState.env)) {
+    if (!STARTUP_ENVIRONMENT_NAMES.has(key.toUpperCase())) Reflect.deleteProperty(processState.env, key)
+  }
+  // Windows native process creation still needs SystemRoot in the OS environment.
+  processState.env = Object.create(null) as NodeJS.ProcessEnv
   const boot = Promise.withResolvers<ProgramBootData>()
   const listeners: Array<(message: ReplyMessage) => void> = []
   let started = false