fix(e2e): bound plugin update log assertions

scripts/e2e/lib/plugins/assertions.mjs

@@ -8,11 +8,14 @@ import {
   readPluginInstallRecords,
   writePluginInstallIndexForE2E,
 } from "../plugin-index-sqlite.mjs";
+import { readTextFileTail } from "../text-file-utils.mjs";
 
 const command = process.argv[2];
 const scratchRoot = process.env.OPENCLAW_PLUGINS_TMP_DIR || os.tmpdir();
 const readJson = (file) => JSON.parse(fs.readFileSync(file, "utf8"));
 const scratchFile = (name) => path.join(scratchRoot, name);
+const ERROR_DETAIL_TAIL_BYTES = 16 * 1024;
+const LOG_SCAN_CHUNK_BYTES = 64 * 1024;
 
 function readClawHubPreflightLimits() {
   return {
@@ -114,6 +117,40 @@ function pathsEqual(left, right) {
   return comparablePath(left) === comparablePath(right);
 }
 
+function fileContainsText(file, needle) {
+  let stat;
+  try {
+    stat = fs.statSync(file);
+  } catch {
+    return false;
+  }
+  if (!stat.isFile() || stat.size <= 0) {
+    return false;
+  }
+  const fd = fs.openSync(file, "r");
+  try {
+    const buffer = Buffer.alloc(Math.min(LOG_SCAN_CHUNK_BYTES, stat.size));
+    let carry = "";
+    let offset = 0;
+    while (offset < stat.size) {
+      const bytesToRead = Math.min(buffer.length, stat.size - offset);
+      const bytesRead = fs.readSync(fd, buffer, 0, bytesToRead, offset);
+      if (bytesRead <= 0) {
+        break;
+      }
+      offset += bytesRead;
+      const text = carry + buffer.subarray(0, bytesRead).toString("utf8");
+      if (text.includes(needle)) {
+        return true;
+      }
+      carry = text.slice(-Math.max(0, needle.length - 1));
+    }
+    return false;
+  } finally {
+    fs.closeSync(fd);
+  }
+}
+
 function getInstallRecords() {
   const configPath = openClawConfigPath();
   const config = readOpenClawConfig();
@@ -288,10 +325,10 @@ function assertSimplePlugin(jsonFile, inspectFile, pluginId, method) {
 }
 
 function assertUpdateOutput(logFile, expectedSnippet) {
-  const output = fs.readFileSync(logFile, "utf8");
-  if (!output.includes(expectedSnippet)) {
+  if (!fileContainsText(logFile, expectedSnippet)) {
+    const outputTail = readTextFileTail(logFile, ERROR_DETAIL_TAIL_BYTES);
     throw new Error(
-      `expected update output to include ${JSON.stringify(expectedSnippet)}:\n${output}`,
+      `expected update output to include ${JSON.stringify(expectedSnippet)}. Output tail:\n${outputTail}`,
     );
   }
 }

test/scripts/plugins-assertions.test.ts

@@ -208,6 +208,40 @@ test -d "$OPENCLAW_PLUGINS_TMP_DIR"
     }
   });
 
+  it("scans plugin update logs without echoing whole files on failure", async () => {
+    const root = mkdtempSync(path.join(tmpdir(), "openclaw-plugin-update-log-"));
+    try {
+      const passRoot = path.join(root, "pass");
+      mkdirSync(passRoot, { recursive: true });
+      writeFileSync(
+        path.join(passRoot, "plugins-dir-update.log"),
+        `Skipping "demo-plugin-dir" (source: path).\n${"x".repeat(256 * 1024)}`,
+        "utf8",
+      );
+      const pass = await runAssertionAsync(["plugin-dir-update-skipped"], {
+        OPENCLAW_PLUGINS_TMP_DIR: passRoot,
+      });
+      expect(pass.status).toBe(0);
+
+      const failRoot = path.join(root, "fail");
+      mkdirSync(failRoot, { recursive: true });
+      writeFileSync(
+        path.join(failRoot, "plugins-dir-update.log"),
+        `${"x".repeat(256 * 1024)}\nmissing marker tail`,
+        "utf8",
+      );
+      const fail = await runAssertionAsync(["plugin-dir-update-skipped"], {
+        OPENCLAW_PLUGINS_TMP_DIR: failRoot,
+      });
+      expect(fail.status).toBe(1);
+      expect(fail.stderr).toContain("Output tail:");
+      expect(fail.stderr).toContain("missing marker tail");
+      expect(fail.stderr.length).toBeLessThan(20 * 1024);
+    } finally {
+      rmSync(root, { recursive: true, force: true });
+    }
+  });
+
   it("cleans npm fixture registry children when readiness times out", () => {
     const root = mkdtempSync(path.join(tmpdir(), "openclaw-plugin-npm-fixture-cleanup-"));
     try {