process: refactor emitWarning

Remove a couple of obsolete checks by refactoring the code with else. Also remove the possibility of an undefined warning. That is neither documented nor does it result in a usable warning.

Author: BridgeAR

lib/internal/process/warning.js

@@ -105,7 +105,7 @@ function setupProcessWarnings() {
  // process.emitWarning(str[, type[, code]][, ctor])
  // process.emitWarning(str[, options])
  process.emitWarning = function(warning, type, code, ctor, now) {
- var detail;
+ let detail;
  if (type !== null && typeof type === 'object' && !Array.isArray(type)) {
  ctor = type.ctor;
  code = type.code;
@@ -117,23 +117,23 @@ function setupProcessWarnings() {
  code = undefined;
  type = 'Warning';
  }
+ if (type !== undefined && typeof type !== 'string') {
+ throw new ERR_INVALID_ARG_TYPE('type', 'string', type);
+ }
  if (typeof code === 'function') {
  ctor = code;
  code = undefined;
- }
- if (code !== undefined && typeof code !== 'string')
+ } else if (code !== undefined && typeof code !== 'string') {
  throw new ERR_INVALID_ARG_TYPE('code', 'string', code);
- if (type !== undefined && typeof type !== 'string')
- throw new ERR_INVALID_ARG_TYPE('type', 'string', type);
- if (warning === undefined || typeof warning === 'string') {
+ }
+ if (typeof warning === 'string') {
  // eslint-disable-next-line no-restricted-syntax
  warning = new Error(warning);
  warning.name = String(type || 'Warning');
  if (code !== undefined) warning.code = code;
  if (detail !== undefined) warning.detail = detail;
  Error.captureStackTrace(warning, ctor || process.emitWarning);
- }
- if (!(warning instanceof Error)) {
+ } else if (!(warning instanceof Error)) {
  throw new ERR_INVALID_ARG_TYPE('warning', ['Error', 'string'], warning);
  }
  if (warning.name === 'DeprecationWarning') {

test/parallel/test-process-emitwarning.js

@@ -43,8 +43,8 @@ class CustomWarning extends Error {
  [testMsg, { type: testType, code: testCode, detail: [] }],
  [testMsg, { type: testType, code: testCode, detail: null }],
  [testMsg, { type: testType, code: testCode, detail: 1 }]
-].forEach((i) => {
- process.emitWarning.apply(null, i);
+].forEach((args) => {
+ process.emitWarning(...args);
 });
 
 const warningNoToString = new CustomWarning();
@@ -57,18 +57,25 @@ warningThrowToString.toString = function() {
 };
 process.emitWarning(warningThrowToString);
 
-const expectedError =
- common.expectsError({ code: 'ERR_INVALID_ARG_TYPE', type: TypeError }, 11);
-
 // TypeError is thrown on invalid input
-assert.throws(() => process.emitWarning(1), expectedError);
-assert.throws(() => process.emitWarning({}), expectedError);
-assert.throws(() => process.emitWarning(true), expectedError);
-assert.throws(() => process.emitWarning([]), expectedError);
-assert.throws(() => process.emitWarning('', '', {}), expectedError);
-assert.throws(() => process.emitWarning('', 1), expectedError);
-assert.throws(() => process.emitWarning('', '', 1), expectedError);
-assert.throws(() => process.emitWarning('', true), expectedError);
-assert.throws(() => process.emitWarning('', '', true), expectedError);
-assert.throws(() => process.emitWarning('', []), expectedError);
-assert.throws(() => process.emitWarning('', '', []), expectedError);
+[
+ [1],
+ [{}],
+ [true],
+ [[]],
+ ['', '', {}],
+ ['', 1],
+ ['', '', 1],
+ ['', true],
+ ['', '', true],
+ ['', []],
+ ['', '', []],
+ [],
+ [undefined, 'foo', 'bar'],
+ [undefined]
+].forEach((args) => {
+ common.expectsError(
+ () => process.emitWarning(...args),
+ { code: 'ERR_INVALID_ARG_TYPE', type: TypeError }
+ );
+});