assert: show diff when doing partial comparisons

PR-URL: #56211 Reviewed-By: Ruben Bridgewater <[email protected]>

Author: Giovanni Bucci

lib/assert.js

@@ -639,10 +639,9 @@ function compareBranch(
 // Check if all expected keys and values match
 for(leti=0;i<keysExpected.length;i++){
 constkey=keysExpected[i];
-assert(
-ReflectHas(actual,key),
-newAssertionError({message: `Expected key ${String(key)} not found in actual object`}),
-);
+if(!ReflectHas(actual,key)){
+returnfalse;
+}
 if(!compareBranch(actual[key],expected[key],comparedObjects)){
 returnfalse;
 }

lib/internal/assert/assertion_error.js

@@ -26,6 +26,7 @@ const{myersDiff, printMyersDiff, printSimpleMyersDiff } = require('internal/as
 
 constkReadableOperator={
 deepStrictEqual: 'Expected values to be strictly deep-equal:',
+partialDeepStrictEqual: 'Expected values to be partially and strictly deep-equal:',
 strictEqual: 'Expected values to be strictly equal:',
 strictEqualObject: 'Expected "actual" to be reference-equal to "expected":',
 deepEqual: 'Expected values to be loosely deep-equal:',
@@ -41,6 +42,8 @@ const kReadableOperator ={
 constkMaxShortStringLength=12;
 constkMaxLongStringLength=512;
 
+constkMethodsWithCustomMessageDiff=['deepStrictEqual','strictEqual','partialDeepStrictEqual'];
+
 functioncopyError(source){
 consttarget=ObjectAssign(
 {__proto__: ObjectGetPrototypeOf(source)},
@@ -210,9 +213,13 @@ function createErrDiff(actual, expected, operator, customMessage){
 constcheckCommaDisparity=actual!=null&&typeofactual==='object';
 constdiff=myersDiff(inspectedSplitActual,inspectedSplitExpected,checkCommaDisparity);
 
-constmyersDiffMessage=printMyersDiff(diff);
+constmyersDiffMessage=printMyersDiff(diff,operator);
 message=myersDiffMessage.message;
 
+if(operator==='partialDeepStrictEqual'){
+header=`${colors.gray}${colors.hasColors ? '' : '+ '}actual${colors.white}${colors.red}- expected${colors.white}`;
+}
+
 if(myersDiffMessage.skipped){
 skipped=true;
 }
@@ -255,7 +262,7 @@ class AssertionError extends Error{
 if(isErrorStackTraceLimitWritable())Error.stackTraceLimit=0;
 
 if(message!=null){
-if(operator==='deepStrictEqual'||operator==='strictEqual'){
+if(kMethodsWithCustomMessageDiff.includes(operator)){
 super(createErrDiff(actual,expected,operator,message));
 }else{
 super(String(message));
@@ -275,7 +282,7 @@ class AssertionError extends Error{
 expected=copyError(expected);
 }
 
-if(operator==='deepStrictEqual'||operator==='strictEqual'){
+if(kMethodsWithCustomMessageDiff.includes(operator)){
 super(createErrDiff(actual,expected,operator,message));
 }elseif(operator==='notDeepStrictEqual'||
 operator==='notStrictEqual'){

lib/internal/assert/myers_diff.js

@@ -122,7 +122,7 @@ function printSimpleMyersDiff(diff){
 return`\n${message}`;
 }
 
-functionprintMyersDiff(diff,simple=false){
+functionprintMyersDiff(diff,operator){
 letmessage='';
 letskipped=false;
 letnopCount=0;
@@ -148,7 +148,11 @@ function printMyersDiff(diff, simple = false){
 }
 
 if(type==='insert'){
-message+=`${colors.green}+${colors.white}${value}\n`;
+if(operator==='partialDeepStrictEqual'){
+message+=`${colors.gray}${colors.hasColors ? ' ' : '+'}${value}${colors.white}\n`;
+}else{
+message+=`${colors.green}+${colors.white}${value}\n`;
+}
 }elseif(type==='delete'){
 message+=`${colors.red}-${colors.white}${value}\n`;
 }elseif(type==='nop'){

test/parallel/test-assert.js

@@ -1351,6 +1351,17 @@ test('Additional assert', () =>{
 }
 );
 
+assert.throws(
+()=>{
+assert.partialDeepStrictEqual({a: true},{a: false},'custom message');
+},
+{
+code: 'ERR_ASSERTION',
+name: 'AssertionError',
+message: 'custom message\n+ actual - expected\n\n{\n+ a: true\n- a: false\n }\n'
+}
+);
+
 {
 letthrew=false;
 try{

test/pseudo-tty/test-assert-colors.js

@@ -1,11 +1,16 @@
+// Flags: --no-warnings
 'use strict';
 require('../common');
 constassert=require('assert').strict;
 
-assert.throws(()=>{
+functionsetup(){
 process.env.FORCE_COLOR='1';
 deleteprocess.env.NODE_DISABLE_COLORS;
 deleteprocess.env.NO_COLOR;
+}
+
+assert.throws(()=>{
+setup();
 assert.deepStrictEqual([1,2,2,2,2],[2,2,2,2,2]);
 },(err)=>{
 constexpected='Expected values to be strictly deep-equal:\n'+
@@ -19,6 +24,48 @@ assert.throws(() =>{
 '\x1B[39m 2,\n'+
 '\x1B[31m-\x1B[39m 2\n'+
 '\x1B[39m ]\n';
+
 assert.strictEqual(err.message,expected);
 returntrue;
 });
+
+{
+assert.throws(()=>{
+setup();
+assert.partialDeepStrictEqual({a: 1,b: 2,c: 3,d: 5},{z: 4,b: 5});
+},(err)=>{
+constexpected='Expected values to be partially and strictly deep-equal:\n'+
+'\x1B[90mactual\x1B[39m \x1B[31m- expected\x1B[39m\n'+
+'\n'+
+'\x1B[39m{\n'+
+'\x1B[90m a: 1,\x1B[39m\n'+
+'\x1B[90m b: 2,\x1B[39m\n'+
+'\x1B[90m c: 3,\x1B[39m\n'+
+'\x1B[90m d: 5\x1B[39m\n'+
+'\x1B[31m-\x1B[39m b: 5,\n'+
+'\x1B[31m-\x1B[39m z: 4\n'+
+'\x1B[39m }\n';
+
+assert.strictEqual(err.message,expected);
+returntrue;
+});
+
+assert.throws(()=>{
+setup();
+assert.partialDeepStrictEqual([1,2,3,5],[4,5]);
+},(err)=>{
+constexpected='Expected values to be partially and strictly deep-equal:\n'+
+'\x1B[90mactual\x1B[39m \x1B[31m- expected\x1B[39m\n'+
+'\n'+
+'\x1B[39m [\n'+
+'\x1B[90m 1,\x1B[39m\n'+
+'\x1B[90m 2,\x1B[39m\n'+
+'\x1B[90m 3,\x1B[39m\n'+
+'\x1B[31m-\x1B[39m 4,\n'+
+'\x1B[39m 5\n'+
+'\x1B[39m ]\n';
+
+assert.strictEqual(err.message,expected);
+returntrue;
+});
+}

test/pseudo-tty/test-assert-no-color.js

@@ -1,3 +1,4 @@
+// Flags: --no-warnings
 'use strict';
 require('../common');
 constassert=require('assert').strict;
@@ -17,3 +18,19 @@ assert.throws(
 '- foo: \'bar\'\n'+
 '- }\n',
 });
+
+{
+assert.throws(
+()=>{
+assert.partialDeepStrictEqual({},{foo: 'bar'});
+},
+{
+message: 'Expected values to be partially and strictly deep-equal:\n'+
+'+ actual - expected\n'+
+'\n'+
+'+{}\n'+
+'-{\n'+
+"- foo: 'bar'\n"+
+'- }\n',
+});
+}