fix(sdk): decode command output as GBK when it is not valid UTF-8 (#1735)

src/backend/tests/plugins/host-commands.test.ts

@@ -1,3 +1,4 @@
+import { EventEmitter } from "node:events";
 import { describe, it, expect } from "vitest";
 import {
   parsePlatformProbe,
@@ -7,6 +8,7 @@ import {
   buildSudoCommand,
   parseUpgradable,
   execCommand,
+  decodeCommandOutput,
 } from "@termix-ssh/plugin-sdk/host-commands";
 
 describe("parsePlatformProbe", () => {
@@ -116,6 +118,32 @@ describe("parseUpgradable", () => {
   });
 });
 
+class FakeStream extends EventEmitter {
+  stderr = new EventEmitter();
+  destroy() {}
+}
+
+function fakeClient(script: (stream: FakeStream) => void) {
+  return {
+    exec: (
+      _command: string,
+      _options: unknown,
+      callback: (err: Error | undefined, stream: FakeStream) => void,
+    ) => {
+      const stream = new FakeStream();
+      callback(undefined, stream);
+      script(stream);
+    },
+  } as never;
+}
+
+// "The system cannot find the path specified." as the GBK bytes a
+// Chinese-locale Windows console actually sends.
+const GBK_PATH_ERROR = Buffer.from(
+  "cfb5cdb3d5d2b2bbb5bdd6b8b6a8b5c4c2b7beb6a1a3",
+  "hex",
+);
+
 describe("execCommand", () => {
   it("leaves the command out of the timeout error", async () => {
     const client = { exec: () => {} } as never;
@@ -124,4 +152,64 @@ describe("execCommand", () => {
       /^Command timeout after 5ms$/,
     );
   });
+
+  it("decodes GBK stderr from a localized Windows host", async () => {
+    const result = await execCommand(
+      fakeClient((stream) => {
+        stream.stderr.emit("data", GBK_PATH_ERROR.subarray(0, 7));
+        stream.stderr.emit("data", GBK_PATH_ERROR.subarray(7));
+        stream.emit("close", 1);
+      }),
+      "dir",
+    );
+    expect(result.stderr).toBe("系统找不到指定的路径。");
+    expect(result.code).toBe(1);
+  });
+
+  it("reassembles a UTF-8 character split across chunks", async () => {
+    const utf8 = Buffer.from("以太网 2", "utf8");
+    const result = await execCommand(
+      fakeClient((stream) => {
+        stream.emit("data", utf8.subarray(0, 4)); // cuts 太 in half
+        stream.emit("data", utf8.subarray(4));
+        stream.emit("close", 0);
+      }),
+      "ipconfig",
+    );
+    expect(result.stdout).toBe("以太网 2");
+  });
+
+  it("passes plain ASCII output through unchanged", async () => {
+    const result = await execCommand(
+      fakeClient((stream) => {
+        stream.emit("data", Buffer.from("ok\n"));
+        stream.stderr.emit("data", Buffer.from("warn\n"));
+        stream.emit("close", 0);
+      }),
+      "echo ok",
+    );
+    expect(result).toEqual({ stdout: "ok\n", stderr: "warn\n", code: 0 });
+  });
+});
+
+describe("decodeCommandOutput", () => {
+  it("keeps valid UTF-8, including the empty buffer", () => {
+    expect(decodeCommandOutput(Buffer.from("以太网 2", "utf8"))).toBe(
+      "以太网 2",
+    );
+    expect(decodeCommandOutput(Buffer.alloc(0))).toBe("");
+  });
+
+  it("falls back to GBK when the bytes are not valid UTF-8", () => {
+    // "以太网 2" in GBK, the interface name of the metrics widget issue.
+    expect(decodeCommandOutput(Buffer.from("d2d4ccabcdf82032", "hex"))).toBe(
+      "以太网 2",
+    );
+    expect(decodeCommandOutput(GBK_PATH_ERROR)).toBe("系统找不到指定的路径。");
+  });
+
+  it("keeps lossy UTF-8 when no decoder matches", () => {
+    // 0xff is a valid byte in neither UTF-8 nor GBK.
+    expect(decodeCommandOutput(Buffer.from([0x68, 0x69, 0xff]))).toBe("hi�");
+  });
 });