From c7cef584e52045810bb478f656a61ceedf9d9b10 Mon Sep 17 00:00:00 2001 From: Ruben Bridgewater Date: Tue, 20 Mar 2018 01:49:29 +0100 Subject: [PATCH] assert: improve assert.throws This switches the assert.throws output to the one used in strict mode if a error object is used for comparison. From now on it will show the complete difference between two objects instead of only showing the first failing property. It also fixes detecting properties with a undefined value and fails in case the thrown error does not contain the value at all. --- lib/assert.js | 53 +++++++++++++------ test/message/assert_throws_stack.out | 8 ++- test/parallel/test-assert-fail-deprecation.js | 6 +-- test/parallel/test-assert-fail.js | 5 +- test/parallel/test-assert.js | 53 ++++++++++++------- 5 files changed, 80 insertions(+), 45 deletions(-) diff --git a/lib/assert.js b/lib/assert.js index ccc1de3a25d0..7200eb32f17d 100644 --- a/lib/assert.js +++ b/lib/assert.js @@ -365,13 +365,38 @@ assert.notStrictEqual = function notStrictEqual(actual, expected, message) { } }; -function compareExceptionKey(actual, expected, key, msg) { - if (!isDeepStrictEqual(actual[key], expected[key])) { +class Comparison { + constructor(obj, keys) { + for (const key of keys) { + if (key in obj) + this[key] = obj[key]; + } + } +} + +function compareExceptionKey(actual, expected, key, message, keys) { + if (!(key in actual) || !isDeepStrictEqual(actual[key], expected[key])) { + if (!message) { + // Create placeholder objects to create a nice output. + const a = new Comparison(actual, keys); + const b = new Comparison(expected, keys); + + const tmpLimit = Error.stackTraceLimit; + Error.stackTraceLimit = 0; + const err = new AssertionError({ + actual: a, + expected: b, + operator: 'deepStrictEqual', + stackStartFn: assert.throws, + errorDiff: ERR_DIFF_EQUAL + }); + Error.stackTraceLimit = tmpLimit; + message = err.message; + } innerFail({ - actual: actual[key], - expected: expected[key], - message: msg || `${key}: expected ${inspect(expected[key])}, ` + - `not ${inspect(actual[key])}`, + actual, + expected, + message, operator: 'throws', stackStartFn: assert.throws }); @@ -388,16 +413,14 @@ function expectedException(actual, expected, msg) { 'expected', ['Function', 'RegExp'], expected ); } - // The name and message could be non enumerable. Therefore test them - // explicitly. - if ('name' in expected) { - compareExceptionKey(actual, expected, 'name', msg); - } - if ('message' in expected) { - compareExceptionKey(actual, expected, 'message', msg); + const keys = Object.keys(expected); + // Special handle errors to make sure the name and the message are compared + // as well. + if (expected instanceof Error) { + keys.push('name', 'message'); } - for (const key of Object.keys(expected)) { - compareExceptionKey(actual, expected, key, msg); + for (const key of keys) { + compareExceptionKey(actual, expected, key, msg, keys); } return true; } diff --git a/test/message/assert_throws_stack.out b/test/message/assert_throws_stack.out index d34bdd247981..71d06a461e14 100644 --- a/test/message/assert_throws_stack.out +++ b/test/message/assert_throws_stack.out @@ -2,7 +2,13 @@ assert.js:* throw new AssertionError(obj); ^ -AssertionError [ERR_ASSERTION]: bar: expected true, not undefined +AssertionError [ERR_ASSERTION]: Input A expected to deepStrictEqual input B: ++ expected - actual + +- Comparison {} ++ Comparison { ++ bar: true ++ } at Object. (*assert_throws_stack.js:*:*) at * at * diff --git a/test/parallel/test-assert-fail-deprecation.js b/test/parallel/test-assert-fail-deprecation.js index 9da26dab3fd1..aab26d427253 100644 --- a/test/parallel/test-assert-fail-deprecation.js +++ b/test/parallel/test-assert-fail-deprecation.js @@ -38,11 +38,7 @@ assert.throws(() => { assert.fail(typeof 1, 'object', new TypeError('another custom message')); }, { name: 'TypeError', - message: 'another custom message', - operator: undefined, - actual: undefined, - expected: undefined, - code: undefined + message: 'another custom message' }); // No third arg (but a fourth arg) diff --git a/test/parallel/test-assert-fail.js b/test/parallel/test-assert-fail.js index fc2b6cc03c1d..e8336e8f2169 100644 --- a/test/parallel/test-assert-fail.js +++ b/test/parallel/test-assert-fail.js @@ -33,8 +33,5 @@ assert.throws(() => { assert.fail(new TypeError('custom message')); }, { name: 'TypeError', - message: 'custom message', - operator: undefined, - actual: undefined, - expected: undefined + message: 'custom message' }); diff --git a/test/parallel/test-assert.js b/test/parallel/test-assert.js index 9964c393edc7..84fef0ee2908 100644 --- a/test/parallel/test-assert.js +++ b/test/parallel/test-assert.js @@ -34,6 +34,12 @@ const { writeFileSync, unlinkSync } = require('fs'); const { inspect } = require('util'); const a = assert; +const colors = process.stdout.isTTY && process.stdout.getColorDepth() > 1; +const start = 'Input A expected to deepStrictEqual input B:'; +const actExp = colors ? + '\u001b[32m+ expected\u001b[39m \u001b[31m- actual\u001b[39m' : + '+ expected - actual'; + assert.ok(a.AssertionError.prototype instanceof Error, 'a.AssertionError instanceof Error'); @@ -440,11 +446,6 @@ common.expectsError( Error.stackTraceLimit = tmpLimit; // Test error diffs. - const colors = process.stdout.isTTY && process.stdout.getColorDepth() > 1; - const start = 'Input A expected to deepStrictEqual input B:'; - const actExp = colors ? - '\u001b[32m+ expected\u001b[39m \u001b[31m- actual\u001b[39m' : - '+ expected - actual'; const plus = colors ? '\u001b[32m+\u001b[39m' : '+'; const minus = colors ? '\u001b[31m-\u001b[39m' : '-'; let message = [ @@ -769,24 +770,32 @@ common.expectsError( errObj.code = 404; assert.throws(errFn, errObj); - errObj.code = '404'; - common.expectsError( + // Fail in case a expected property is undefined and not existent on the + // error. + errObj.foo = undefined; + assert.throws( () => assert.throws(errFn, errObj), { code: 'ERR_ASSERTION', - type: assert.AssertionError, - message: 'code: expected \'404\', not 404' + name: 'AssertionError [ERR_ASSERTION]', + message: `${start}\n${actExp}\n\n` + + " Comparison {\n name: 'TypeError',\n" + + " message: 'Wrong value',\n- code: 404\n" + + '+ code: 404,\n+ foo: undefined\n }' } ); - errObj.code = 404; - errObj.foo = 'bar'; - common.expectsError( + // Show multiple wrong properties at the same time. + errObj.code = '404'; + assert.throws( () => assert.throws(errFn, errObj), { code: 'ERR_ASSERTION', - type: assert.AssertionError, - message: 'foo: expected \'bar\', not undefined' + name: 'AssertionError [ERR_ASSERTION]', + message: `${start}\n${actExp}\n\n` + + " Comparison {\n name: 'TypeError',\n" + + " message: 'Wrong value',\n- code: 404\n" + + "+ code: '404',\n+ foo: undefined\n }" } ); @@ -810,20 +819,24 @@ common.expectsError( ); assert.throws(() => { throw new Error('e'); }, new Error('e')); - common.expectsError( + assert.throws( () => assert.throws(() => { throw new TypeError('e'); }, new Error('e')), { - type: assert.AssertionError, + name: 'AssertionError [ERR_ASSERTION]', code: 'ERR_ASSERTION', - message: "name: expected 'Error', not 'TypeError'" + message: `${start}\n${actExp}\n\n` + + " Comparison {\n- name: 'TypeError',\n+ name: 'Error'," + + "\n message: 'e'\n }" } ); - common.expectsError( + assert.throws( () => assert.throws(() => { throw new Error('foo'); }, new Error('')), { - type: assert.AssertionError, + name: 'AssertionError [ERR_ASSERTION]', code: 'ERR_ASSERTION', - message: "message: expected '', not 'foo'" + message: `${start}\n${actExp}\n\n` + + " Comparison {\n name: 'Error',\n- message: 'foo'" + + "\n+ message: ''\n }" } );