util: special handle maxArrayLength while grouping arrays

This makes sure that large arrays with lots of small entries ignore the `... n more item(s)` part since it often resulted in output that users did not expect. Now that part is printed on a separate line to indicate extra entries. PR-URL: #28059 Refs: #27690 Reviewed-By: Michaël Zasso <[email protected]> Reviewed-By: Benjamin Gruenbaum <[email protected]> Reviewed-By: Rich Trott <[email protected]>

Author: BridgeAR

lib/internal/util/inspect.js

@@ -946,12 +946,17 @@ function groupArrayElements(ctx, output){
 lettotalLength=0;
 letmaxLength=0;
 leti=0;
+letoutputLength=output.length;
+if(ctx.maxArrayLength<output.length){
+// This makes sure the "... n more items" part is not taken into account.
+outputLength--;
+}
 constseparatorSpace=2;// Add 1 for the space and 1 for the separator.
-constdataLen=newArray(output.length);
+constdataLen=newArray(outputLength);
 // Calculate the total length of all output entries and the individual max
 // entries length of all output entries. We have to remove colors first,
 // otherwise the length would not be calculated properly.
-for(;i<output.length;i++){
+for(;i<outputLength;i++){
 constlen=ctx.colors ? removeColors(output[i]).length : output[i].length;
 dataLen[i]=len;
 totalLength+=len+separatorSpace;
@@ -979,7 +984,7 @@ function groupArrayElements(ctx, output){
 // The added bias slightly increases the columns for short entries.
 Math.round(
 Math.sqrt(
-approxCharHeights*(actualMax-bias)*output.length
+approxCharHeights*(actualMax-bias)*outputLength
 )/(actualMax-bias)
 ),
 // Do not exceed the breakLength.
@@ -1003,20 +1008,23 @@ function groupArrayElements(ctx, output){
 firstLineMaxLength=dataLen[i];
 }
 // Each iteration creates a single line of grouped entries.
-for(i=0;i<output.length;i+=columns){
+for(i=0;i<outputLength;i+=columns){
 // Calculate extra color padding in case it's active. This has to be done
 // line by line as some lines might contain more colors than others.
 letcolorPadding=output[i].length-dataLen[i];
 // Add padding to the first column of the output.
 letstr=output[i].padStart(firstLineMaxLength+colorPadding,' ');
 // The last lines may contain less entries than columns.
-constmax=Math.min(i+columns,output.length);
+constmax=Math.min(i+columns,outputLength);
 for(varj=i+1;j<max;j++){
 colorPadding=output[j].length-dataLen[j];
 str+=`, ${output[j].padStart(maxLength+colorPadding,' ')}`;
 }
 tmp.push(str);
 }
+if(ctx.maxArrayLength<output.length){
+tmp.push(output[outputLength]);
+}
 output=tmp;
 }
 returnoutput;

test/parallel/test-util-inspect.js

@@ -2175,7 +2175,7 @@ assert.strictEqual(
 [1,2,{a: 1,b: 2,c: 3}]
 ],
 c: ['foo',4,444444],
-d: Array.from({length: 100}).map((e,i)=>{
+d: Array.from({length: 101}).map((e,i)=>{
 returni%2===0 ? i*i : i;
 }),
 e: Array(6).fill('foobar'),
@@ -2224,7 +2224,8 @@ assert.strictEqual(
 ' 77, 6084, 79, 6400, 81, 6724, 83,',
 ' 7056, 85, 7396, 87, 7744, 89, 8100,',
 ' 91, 8464, 93, 8836, 95, 9216, 97,',
-' 9604, 99',
+' 9604, 99,',
+' ... 1 more item',
 ' ],',
 ' e: [',
 " 'foobar',",