errors: eliminate circular dependency on assert

PR-URL: #15002
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: jasnell

lib/internal/errors.js

@@ -12,7 +12,6 @@ const kCode = Symbol('code');
 const messages = new Map();
 
 // Lazily loaded
-var assert = null;
 var util = null;
 
 function makeNodeError(Base) {
@@ -60,11 +59,22 @@ class AssertionError extends Error {
   }
 }
 
+// This is defined here instead of using the assert module to avoid a
+// circular dependency. The effect is largely the same.
+function internalAssert(condition, message) {
+  if (!condition) {
+    throw new AssertionError({
+      message,
+      actual: false,
+      expected: true,
+      operator: '=='
+    });
+  }
+}
+
 function message(key, args) {
-  if (assert === null) assert = require('assert');
-  assert.strictEqual(typeof key, 'string');
   const msg = messages.get(key);
-  assert(msg, `An invalid error message key was used: ${key}.`);
+  internalAssert(msg, `An invalid error message key was used: ${key}.`);
   let fmt;
   if (typeof msg === 'function') {
     fmt = msg;
@@ -184,6 +194,11 @@ E('ERR_HTTP2_UNSUPPORTED_PROTOCOL',
   (protocol) => `protocol "${protocol}" is unsupported.`);
 E('ERR_INDEX_OUT_OF_RANGE', 'Index out of range');
 E('ERR_INVALID_ARG_TYPE', invalidArgType);
+E('ERR_INVALID_ARRAY_LENGTH',
+  (name, len, actual) => {
+    internalAssert(typeof actual === 'number', 'actual must be a number');
+    return `The array "${name}" (length ${actual}) must be of length ${len}.`;
+  });
 E('ERR_INVALID_ASYNC_ID', (type, id) => `Invalid ${type} value: ${id}`);
 E('ERR_INVALID_CALLBACK', 'callback must be a function');
 E('ERR_INVALID_FD', (fd) => `"fd" must be a positive integer: ${fd}`);
@@ -239,7 +254,7 @@ E('ERR_VALID_PERFORMANCE_ENTRY_TYPE',
 // Add new errors from here...
 
 function invalidArgType(name, expected, actual) {
-  assert(name, 'name is required');
+  internalAssert(name, 'name is required');
   var msg = `The "${name}" argument must be ${oneOf(expected, 'type')}`;
   if (arguments.length >= 3) {
     msg += `. Received type ${actual !== null ? typeof actual : 'null'}`;
@@ -248,7 +263,7 @@ function invalidArgType(name, expected, actual) {
 }
 
 function missingArgs(...args) {
-  assert(args.length > 0, 'At least one arg needs to be specified');
+  internalAssert(args.length > 0, 'At least one arg needs to be specified');
   let msg = 'The ';
   const len = args.length;
   args = args.map((a) => `"${a}"`);
@@ -268,11 +283,12 @@ function missingArgs(...args) {
 }
 
 function oneOf(expected, thing) {
-  assert(expected, 'expected is required');
-  assert(typeof thing === 'string', 'thing is required');
+  internalAssert(expected, 'expected is required');
+  internalAssert(typeof thing === 'string', 'thing is required');
   if (Array.isArray(expected)) {
     const len = expected.length;
-    assert(len > 0, 'At least one expected value needs to be specified');
+    internalAssert(len > 0,
+                   'At least one expected value needs to be specified');
     expected = expected.map((i) => String(i));
     if (len > 2) {
       return `one of ${thing} ${expected.slice(0, len - 1).join(', ')}, or ` +

test/parallel/test-internal-errors.js

@@ -5,12 +5,9 @@ const common = require('../common');
 const errors = require('internal/errors');
 const assert = require('assert');
 
-const errMessages = {
-  objectString: /^'object' === 'string'$/,
-  booleanString: /^'boolean' === 'string'$/,
-  numberString: /^'number' === 'string'$/,
-  invalidKey: /^An invalid error message key was used: TEST_FOO_KEY\.$/,
-};
+function invalidKey(key) {
+  return new RegExp(`^An invalid error message key was used: ${key}\\.$`);
+}
 
 errors.E('TEST_ERROR_1', 'Error for testing purposes: %s');
 errors.E('TEST_ERROR_2', (a, b) => `${a} ${b}`);
@@ -50,86 +47,86 @@ assert.throws(
   () => new errors.Error('TEST_FOO_KEY'),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.invalidKey
+    message: invalidKey('TEST_FOO_KEY')
   }));
 // Calling it twice yields same result (using the key does not create it)
 assert.throws(
   () => new errors.Error('TEST_FOO_KEY'),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.invalidKey
+    message: invalidKey('TEST_FOO_KEY')
   }));
 assert.throws(
   () => new errors.Error(1),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.numberString
+    message: invalidKey(1)
   }));
 assert.throws(
   () => new errors.Error({}),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.objectString
+    message: invalidKey('\\[object Object\\]')
   }));
 assert.throws(
   () => new errors.Error([]),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.objectString
+    message: invalidKey('')
   }));
 assert.throws(
   () => new errors.Error(true),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.booleanString
+    message: invalidKey('true')
   }));
 assert.throws(
   () => new errors.TypeError(1),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.numberString
+    message: invalidKey(1)
   }));
 assert.throws(
   () => new errors.TypeError({}),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.objectString
+    message: invalidKey('\\[object Object\\]')
   }));
 assert.throws(
   () => new errors.TypeError([]),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.objectString
+    message: invalidKey('')
   }));
 assert.throws(
   () => new errors.TypeError(true),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.booleanString
+    message: invalidKey('true')
   }));
 assert.throws(
   () => new errors.RangeError(1),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.numberString
+    message: invalidKey(1)
   }));
 assert.throws(
   () => new errors.RangeError({}),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.objectString
+    message: invalidKey('\\[object Object\\]')
   }));
 assert.throws(
   () => new errors.RangeError([]),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.objectString
+    message: invalidKey('')
   }));
 assert.throws(
   () => new errors.RangeError(true),
   common.expectsError({
     code: 'ERR_ASSERTION',
-    message: errMessages.booleanString
+    message: invalidKey('true')
   }));