fix(cli-agent-bridge): preserve config cleanup failures

Author: Hylouis233

plugins/Hylouis233/cli-agent-bridge/server.mjs

@@ -317,7 +317,7 @@ async function readBackendConfiguration(file, options = {}) {
     });
     if (options.cancel?.controller === controller) options.cancel.controller = null;
     if (result.treeTerminated !== true) {
-      throw new Error(
+      throw new BackendConfigurationCleanupError(
         "backend configuration reader cleanup could not be confirmed: " +
         (result.terminationError || "process tree termination was unconfirmed"),
       );
@@ -354,7 +354,8 @@ export async function loadBackends(options = {}) {
     try {
       return await readBackendConfiguration(file, options);
     } catch (error) {
-      if (error instanceof OperationCancelledError || error instanceof DeadlineExceededError) {
+      if (error instanceof OperationCancelledError || error instanceof DeadlineExceededError ||
+          error instanceof BackendConfigurationCleanupError) {
         throw error;
       }
       throw new Error("cannot load explicit backend configuration " + file + ": " + error.message);
@@ -364,7 +365,8 @@ export async function loadBackends(options = {}) {
   try {
     return await readBackendConfiguration(bundled, options);
   } catch (error) {
-    if (error instanceof OperationCancelledError || error instanceof DeadlineExceededError) {
+    if (error instanceof OperationCancelledError || error instanceof DeadlineExceededError ||
+        error instanceof BackendConfigurationCleanupError) {
       throw error;
     }
     return FALLBACK_BACKENDS;
@@ -1294,6 +1296,7 @@ function snapshotFailure(label, result) {
 class OperationCancelledError extends Error {}
 class DeadlineExceededError extends Error {}
 class InvalidArgumentsError extends Error {}
+class BackendConfigurationCleanupError extends Error {}
 class GitProcessTreeUnconfirmedError extends Error {
   constructor(label, terminationError, quarantine = null) {
     super(label + " process tree could not be confirmed terminated: " + terminationError);

plugins/Hylouis233/cli-agent-bridge/tests/server.test.mjs

@@ -1322,7 +1322,6 @@ test("backend configuration cleanup uncertainty outranks cancellation", async (c
     stall: process.env.CLI_AGENT_BRIDGE_TEST_BACKEND_CONFIG_READ_STALL_FILE,
   };
   process.env.NODE_ENV = "test";
-  process.env.CLI_AGENT_BRIDGE_BACKENDS = config;
   process.env.CLI_AGENT_BRIDGE_TEST_BACKEND_CONFIG_READ_STALL_FILE = path.join(root, "unused");
   context.after(() => {
     if (saved.nodeEnv === undefined) delete process.env.NODE_ENV;
@@ -1332,22 +1331,27 @@ test("backend configuration cleanup uncertainty outranks cancellation", async (c
     if (saved.stall === undefined) delete process.env.CLI_AGENT_BRIDGE_TEST_BACKEND_CONFIG_READ_STALL_FILE;
     else process.env.CLI_AGENT_BRIDGE_TEST_BACKEND_CONFIG_READ_STALL_FILE = saved.stall;
   });
-  const cancel = testCancellation();
-  await assert.rejects(loadBackends({
-    cancel,
-    commandRunner: async () => {
-      cancel.cancel();
-      return {
-        treeTerminated: false,
-        terminationError: "fixture cleanup uncertainty",
-        timedOut: false,
-        exitCode: 0,
-        stderr: "",
-        stdout: "{}",
-        stdoutTruncated: false,
-      };
-    },
-  }), /cleanup could not be confirmed.*fixture cleanup uncertainty/iu);
+  for (const explicitOverride of [true, false]) {
+    if (explicitOverride) process.env.CLI_AGENT_BRIDGE_BACKENDS = config;
+    else delete process.env.CLI_AGENT_BRIDGE_BACKENDS;
+    const cancel = testCancellation();
+    await assert.rejects(loadBackends({
+      cancel,
+      commandRunner: async () => {
+        cancel.cancel();
+        return {
+          treeTerminated: false,
+          terminationError: "fixture cleanup uncertainty",
+          timedOut: false,
+          exitCode: 0,
+          stderr: "",
+          stdout: "{}",
+          stdoutTruncated: false,
+        };
+      },
+    }), /cleanup could not be confirmed.*fixture cleanup uncertainty/iu,
+    explicitOverride ? "explicit override" : "bundled configuration");
+  }
 });
 
 test("an unset backend override still loads the bundled configuration", async (context) => {