util: add maxArrayLength option to Set and Map

PR-URL: #43576
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: cola119

doc/api/util.md

@@ -485,6 +485,9 @@ stream.write('With ES6');
 <!-- YAML
 added: v0.3.0
 changes:
+ - version: REPLACEME
+ pr-url: https://github.com/nodejs/node/pull/43576
+ description: add support for `maxArrayLength` when inspecting `Set` and `Map`.
  - version:
  - v17.3.0
  - v16.14.0
@@ -586,8 +589,9 @@ changes:
 *`showProxy` {boolean} If `true`, `Proxy` inspection includes
  the [`target` and `handler`][] objects. **Default:**`false`.
 *`maxArrayLength` {integer} Specifies the maximum number of `Array`,
-[`TypedArray`][], [`WeakMap`][], and [`WeakSet`][] elements to include when
- formatting. Set to `null` or `Infinity` to show all elements. Set to `0` or
+[`TypedArray`][], [`Map`][], [`Set`][], [`WeakMap`][],
+ and [`WeakSet`][] elements to include when formatting.
+ Set to `null` or `Infinity` to show all elements. Set to `0` or
  negative to show no elements. **Default:**`100`.
 *`maxStringLength` {integer} Specifies the maximum number of characters to
  include when formatting. Set to `null` or `Infinity` to show all elements.

lib/internal/util/inspect.js

@@ -1553,6 +1553,8 @@ function addNumericSeparatorEnd(integerString) {
 `${result}${integerString.slice(i)}`;
 }
 
+constremainingText=(remaining)=>`... ${remaining} more item${remaining>1 ? 's' : ''}`;
+
 functionformatNumber(fn,number,numericSeparator){
 if(!numericSeparator){
 // Format -0 as '-0'. Checking `number === -0` won't distinguish 0 from -0.
@@ -1679,7 +1681,7 @@ function formatSpecialArray(ctx, value, recurseTimes, maxLength, output, i) {
 output.push(ctx.stylize(message,'undefined'));
 }
 }elseif(remaining>0){
-output.push(`... ${remaining} more item${remaining>1 ? 's' : ''}`);
+output.push(remainingText(remaining));
 }
 returnoutput;
 }
@@ -1717,7 +1719,7 @@ function formatArray(ctx, value, recurseTimes) {
 output.push(formatProperty(ctx,value,recurseTimes,i,kArrayType));
 }
 if(remaining>0)
-output.push(`... ${remaining} more item${remaining>1 ? 's' : ''}`);
+output.push(remainingText(remaining));
 returnoutput;
 }
 
@@ -1732,7 +1734,7 @@ function formatTypedArray(value, length, ctx, ignored, recurseTimes) {
 output[i]=elementFormatter(ctx.stylize,value[i],ctx.numericSeparator);
 }
 if(remaining>0){
-output[maxLength]=`... ${remaining} more item${remaining>1 ? 's' : ''}`;
+output[maxLength]=remainingText(remaining);
 }
 if(ctx.showHidden){
 // .buffer goes last, it's not a primitive like the others.
@@ -1754,22 +1756,40 @@ function formatTypedArray(value, length, ctx, ignored, recurseTimes) {
 }
 
 functionformatSet(value,ctx,ignored,recurseTimes){
+constlength=value.size;
+constmaxLength=MathMin(MathMax(0,ctx.maxArrayLength),length);
+constremaining=length-maxLength;
 constoutput=[];
 ctx.indentationLvl+=2;
+leti=0;
 for(constvofvalue){
+if(i>=maxLength)break;
 ArrayPrototypePush(output,formatValue(ctx,v,recurseTimes));
+i++;
+}
+if(remaining>0){
+ArrayPrototypePush(output,remainingText(remaining));
 }
 ctx.indentationLvl-=2;
 returnoutput;
 }
 
 functionformatMap(value,ctx,ignored,recurseTimes){
+constlength=value.size;
+constmaxLength=MathMin(MathMax(0,ctx.maxArrayLength),length);
+constremaining=length-maxLength;
 constoutput=[];
 ctx.indentationLvl+=2;
+leti=0;
 for(const{0: k,1: v}ofvalue){
+if(i>=maxLength)break;
 output.push(
 `${formatValue(ctx,k,recurseTimes)} => ${formatValue(ctx,v,recurseTimes)}`
 );
+i++;
+}
+if(remaining>0){
+ArrayPrototypePush(output,remainingText(remaining));
 }
 ctx.indentationLvl-=2;
 returnoutput;
@@ -1792,8 +1812,7 @@ function formatSetIterInner(ctx, recurseTimes, entries, state) {
 }
 constremaining=entries.length-maxLength;
 if(remaining>0){
-ArrayPrototypePush(output,
-`... ${remaining} more item${remaining>1 ? 's' : ''}`);
+ArrayPrototypePush(output,remainingText(remaining));
 }
 returnoutput;
 }
@@ -1831,7 +1850,7 @@ function formatMapIterInner(ctx, recurseTimes, entries, state) {
 }
 ctx.indentationLvl-=2;
 if(remaining>0){
-output.push(`... ${remaining} more item${remaining>1 ? 's' : ''}`);
+output.push(remainingText(remaining));
 }
 returnoutput;
 }

test/parallel/test-util-inspect.js

@@ -1172,6 +1172,7 @@ if (typeof Symbol !== 'undefined') {
 {
 assert.strictEqual(util.inspect(newSet()),'Set(0) {}');
 assert.strictEqual(util.inspect(newSet([1,2,3])),'Set(3) { 1, 2, 3 }');
+assert.strictEqual(util.inspect(newSet([1,2,3]),{maxArrayLength: 1}),'Set(3) { 1, ... 2 more items }');
 constset=newSet(['foo']);
 set.bar=42;
 assert.strictEqual(
@@ -1192,6 +1193,8 @@ if (typeof Symbol !== 'undefined') {
 assert.strictEqual(util.inspect(newMap()),'Map(0) {}');
 assert.strictEqual(util.inspect(newMap([[1,'a'],[2,'b'],[3,'c']])),
 "Map(3) { 1 => 'a', 2 => 'b', 3 => 'c' }");
+assert.strictEqual(util.inspect(newMap([[1,'a'],[2,'b'],[3,'c']]),{maxArrayLength: 1}),
+"Map(3) { 1 => 'a', ... 2 more items }");
 constmap=newMap([['foo',null]]);
 map.bar=42;
 assert.strictEqual(util.inspect(map,true),