snapshot of https://github.com/zulip/zulip.git @ 48c69911c7dd4e03b20552eb3bd77ad8151c1357 (2026-09-15)

web/tests/lib/zblueslip.cjs

@@ -0,0 +1,123 @@
+"use strict";
+
+const assert = require("node:assert/strict");
+
+function make_zblueslip() {
+    const lib = {};
+
+    const opts = {
+        // Silently swallow all debug, log and info calls.
+        debug: false,
+        log: false,
+        info: false,
+        // Check against expected error values for the following.
+        warn: true,
+        error: true,
+    };
+    const names = Object.keys(opts);
+
+    // For fatal messages, we should use assert.throws
+    /* istanbul ignore next */
+    lib.fatal = (msg) => {
+        throw new Error(msg);
+    };
+
+    // Store valid test data for options.
+    lib.test_data = {};
+    lib.test_logs = {};
+
+    for (const name of names) {
+        lib.test_data[name] = [];
+        lib.test_logs[name] = [];
+    }
+
+    lib.expect = (name, message, expected_count = 1) => {
+        assert.notEqual(opts[name], undefined, `unexpected arg for expect: ${name}`);
+        assert.ok(
+            expected_count > 0 && Number.isSafeInteger(expected_count),
+            "expected count should be a positive integer",
+        );
+        const obj = {message, count: 0, expected_count};
+        lib.test_data[name].push(obj);
+    };
+
+    const check_seen_messages = () => {
+        for (const name of names) {
+            const logs = lib.test_logs[name];
+            const data = lib.test_data[name];
+            for (const obj of logs) {
+                const message = obj.message;
+                const i = data.findIndex((x) => x.message === message);
+                if (i === -1) {
+                    // Only throw this for message types we want to explicitly track.
+                    // For example, we do not want to throw here for debug messages.
+                    if (opts[name] ?? false) {
+                        throw new Error(`Unexpected '${name}' message: ${message}`);
+                    }
+                    continue;
+                }
+                data[i].count += 1;
+            }
+
+            for (const obj of data) {
+                const message = obj.message;
+                assert.equal(
+                    obj.count,
+                    obj.expected_count,
+                    `Expected ${obj.expected_count} of '${name}': ${message}`,
+                );
+            }
+        }
+    };
+
+    lib.reset = (skip_checks = false) => {
+        if (!skip_checks) {
+            check_seen_messages();
+        }
+
+        for (const name of names) {
+            lib.test_data[name] = [];
+            lib.test_logs[name] = [];
+        }
+    };
+
+    lib.get_test_logs = (name) => lib.test_logs[name];
+
+    // Create logging functions
+    for (const name of names) {
+        if (!(opts[name] ?? false)) {
+            // should just log the message.
+            lib[name] = function (message, more_info, cause) {
+                lib.test_logs[name].push({message, more_info, cause});
+            };
+            continue;
+        }
+        lib[name] = function (message, more_info, cause) {
+            /* istanbul ignore if */
+            if (typeof message !== "string") {
+                // We may catch exceptions in blueslip, and if
+                // so our stub should include that.
+                if (message.toString().includes("exception")) {
+                    message = message.toString();
+                } else {
+                    throw new Error("message should be string: " + message);
+                }
+            }
+            lib.test_logs[name].push({message, more_info, cause});
+            const matched_error_message = lib.test_data[name].some((x) => x.message === message);
+            const exact_match_fail = !matched_error_message;
+            if (exact_match_fail) {
+                const error = new Error(
+                    `Invalid ${name} message: "${message}".`,
+                    cause === undefined ? {} : {cause},
+                );
+                error.blueslip = true;
+                throw error;
+            }
+        };
+    }
+
+    return lib;
+}
+
+module.exports = make_zblueslip();