Coordinate shell and formatter processes with workspace source saves

packages/core/src/formatter.ts

@@ -5,6 +5,7 @@ import { ChildProcess } from "effect/unstable/process"
 import path from "path"
 import { makeLocationNode } from "@opencode/util/effect/app-node"
 import { AppProcess } from "@opencode/util/process"
+import { ProcessWriteBarrier } from "@opencode/util/process-write-barrier"
 import { Location } from "./location.js"
 import type { Info } from "./formatter/builtins.js"
 import { State } from "./state.js"
@@ -64,14 +65,16 @@ const layer = Layer.effect(
         yield* Effect.logInfo("formatting file", { file: filepath, command: cmd })
         const result = yield* processes
           .run(
-            ChildProcess.make(cmd[0], cmd.slice(1), {
-              cwd: location.directory,
-              env: formatter.environment,
-              extendEnv: true,
-              stdin: "ignore",
-              stdout: "ignore",
-              stderr: "ignore",
-            }),
+            ProcessWriteBarrier.guard(
+              ChildProcess.make(cmd[0], cmd.slice(1), {
+                cwd: location.directory,
+                env: formatter.environment,
+                extendEnv: true,
+                stdin: "ignore",
+                stdout: "ignore",
+                stderr: "ignore",
+              }),
+            ),
           )
           .pipe(
             Effect.catch((error) =>

packages/core/src/shell.ts

@@ -6,6 +6,7 @@ import { ChildProcess } from "effect/unstable/process"
 import { produce } from "immer"
 import { Shell } from "@opencode/schema/shell"
 import { AppProcess } from "@opencode/util/process"
+import { ProcessWriteBarrier } from "@opencode/util/process-write-barrier"
 import { makeGlobalNode, makeLocationNode } from "@opencode/util/effect/app-node"
 import { FSUtil } from "@opencode/util/fs-util"
 import { Bus } from "./bus.js"
@@ -343,13 +344,15 @@ const layer = () =>
             Effect.gen(function* () {
               const handle = yield* environment.spawner
                 .spawn(
-                  ChildProcess.make(invocation.shell, args, {
-                    cwd: invocation.cwd,
-                    env: invocation.env,
-                    stdin: "ignore",
-                    detached: process.platform !== "win32",
-                    forceKillAfter: Duration.seconds(3),
-                  }),
+                  ProcessWriteBarrier.guard(
+                    ChildProcess.make(invocation.shell, args, {
+                      cwd: invocation.cwd,
+                      env: invocation.env,
+                      stdin: "ignore",
+                      detached: process.platform !== "win32",
+                      forceKillAfter: Duration.seconds(3),
+                    }),
+                  ),
                 )
                 .pipe(
                   Effect.mapError((cause) => new AppProcess.AppProcessError({ command: invocation.command, cause })),

packages/core/test/fixture/process-write-barrier.py

@@ -0,0 +1,25 @@
+"""Exercise the process wrapper protocol without a platform lease service."""
+
+import json
+import os
+from pathlib import Path
+import signal
+import subprocess
+import sys
+
+assert sys.argv[1:3] == ["run", "--root"]
+assert sys.argv[4] == "--"
+root = Path(sys.argv[3])
+with (root / "invocations.jsonl").open("a") as output:
+    output.write(json.dumps({"args": sys.argv[5:], "isolated": sys.flags.isolated}) + "\n")
+if (root / "blocked").exists():
+    sys.exit(73)
+
+child = subprocess.Popen(sys.argv[5:], close_fds=False)
+for number in (signal.SIGTERM, signal.SIGINT, signal.SIGHUP):
+    signal.signal(number, lambda number, frame: child.send_signal(number))
+status = child.wait()
+if status < 0:
+    signal.signal(-status, signal.SIG_DFL)
+    os.kill(os.getpid(), -status)
+sys.exit(status)