util: fix breakLength: Infinity for deep objects

When `util.inspect` is called with `breakLength: Infinity`, it should
always format the output as a single line. However, the existing logic
for compact arrays (`groupArrayElements`) and deep objects ignored this
when the depth was large or the array was long.

This commit updates `groupArrayElements` to return early if
`breakLength === Infinity`, preventing column grouping. It also
updates `reduceToSingleString` to bypass the depth checks when
`breakLength === Infinity`, ensuring all deep objects are consolidated.

Fixes: #60475
Signed-off-by: Rohith Pariki <rohithpariki@gmail.com>

Author: RohithPariki

lib/internal/util/inspect.js

@@ -2052,6 +2052,9 @@ function formatError(err, constructor, tag, ctx, keys) {
 }
 
 function groupArrayElements(ctx, output, value) {
+  if (ctx.breakLength === Infinity) {
+    return output;
+  }
   let totalLength = 0;
   let maxLength = 0;
   let i = 0;
@@ -2681,7 +2684,8 @@ function reduceToSingleString(
       // Consolidate all entries of the local most inner depth up to
       // `ctx.compact`, as long as the properties are smaller than
       // `ctx.breakLength`.
-      if (ctx.currentDepth - recurseTimes < ctx.compact &&
+      if ((ctx.breakLength === Infinity ||
+           ctx.currentDepth - recurseTimes < ctx.compact) &&
           entries === output.length) {
         // Line up all entries on a single line in case the entries do not
         // exceed `breakLength`. Add 10 as constant to start next to all other

test/parallel/test-util-inspect.js

@@ -3053,18 +3053,19 @@ assert.strictEqual(
 
   out = util.inspect(obj, { compact: 1, breakLength: Infinity, colors: true });
 
+  const inlineArray = [
+    "\u001b[32m'foobar'\u001b[39m", "\u001b[32m'baz'\u001b[39m",
+    "\u001b[32m'foobar'\u001b[39m", "\u001b[32m'baz'\u001b[39m",
+    "\u001b[32m'foobar'\u001b[39m", "\u001b[32m'baz'\u001b[39m",
+    "\u001b[32m'foobar'\u001b[39m", "\u001b[32m'baz'\u001b[39m",
+    "\u001b[32m'foobar'\u001b[39m",
+  ];
   expected = [
     '{',
     '  a: {',
     '    b: { x: \u001b[33m5\u001b[39m, c: \u001b[36m[Object]\u001b[39m }',
     '  },',
-    '  b: [',
-    "    \u001b[32m'foobar'\u001b[39m, \u001b[32m'baz'\u001b[39m,",
-    "    \u001b[32m'foobar'\u001b[39m, \u001b[32m'baz'\u001b[39m,",
-    "    \u001b[32m'foobar'\u001b[39m, \u001b[32m'baz'\u001b[39m,",
-    "    \u001b[32m'foobar'\u001b[39m, \u001b[32m'baz'\u001b[39m,",
-    "    \u001b[32m'foobar'\u001b[39m",
-    '  ]',
+    `  b: [ ${inlineArray.join(', ')} ]`,
     '}',
   ].join('\n');
 
@@ -3073,25 +3074,8 @@ assert.strictEqual(
   obj = Array.from({ length: 60 }).map((e, i) => i);
   out = util.inspect(obj, { compact: 1, breakLength: Infinity, colors: true });
 
-  expected = [
-    '[',
-    '   \u001b[33m0\u001b[39m,  \u001b[33m1\u001b[39m,  \u001b[33m2\u001b[39m,  \u001b[33m3\u001b[39m,',
-    '   \u001b[33m4\u001b[39m,  \u001b[33m5\u001b[39m,  \u001b[33m6\u001b[39m,  \u001b[33m7\u001b[39m,',
-    '   \u001b[33m8\u001b[39m,  \u001b[33m9\u001b[39m, \u001b[33m10\u001b[39m, \u001b[33m11\u001b[39m,',
-    '  \u001b[33m12\u001b[39m, \u001b[33m13\u001b[39m, \u001b[33m14\u001b[39m, \u001b[33m15\u001b[39m,',
-    '  \u001b[33m16\u001b[39m, \u001b[33m17\u001b[39m, \u001b[33m18\u001b[39m, \u001b[33m19\u001b[39m,',
-    '  \u001b[33m20\u001b[39m, \u001b[33m21\u001b[39m, \u001b[33m22\u001b[39m, \u001b[33m23\u001b[39m,',
-    '  \u001b[33m24\u001b[39m, \u001b[33m25\u001b[39m, \u001b[33m26\u001b[39m, \u001b[33m27\u001b[39m,',
-    '  \u001b[33m28\u001b[39m, \u001b[33m29\u001b[39m, \u001b[33m30\u001b[39m, \u001b[33m31\u001b[39m,',
-    '  \u001b[33m32\u001b[39m, \u001b[33m33\u001b[39m, \u001b[33m34\u001b[39m, \u001b[33m35\u001b[39m,',
-    '  \u001b[33m36\u001b[39m, \u001b[33m37\u001b[39m, \u001b[33m38\u001b[39m, \u001b[33m39\u001b[39m,',
-    '  \u001b[33m40\u001b[39m, \u001b[33m41\u001b[39m, \u001b[33m42\u001b[39m, \u001b[33m43\u001b[39m,',
-    '  \u001b[33m44\u001b[39m, \u001b[33m45\u001b[39m, \u001b[33m46\u001b[39m, \u001b[33m47\u001b[39m,',
-    '  \u001b[33m48\u001b[39m, \u001b[33m49\u001b[39m, \u001b[33m50\u001b[39m, \u001b[33m51\u001b[39m,',
-    '  \u001b[33m52\u001b[39m, \u001b[33m53\u001b[39m, \u001b[33m54\u001b[39m, \u001b[33m55\u001b[39m,',
-    '  \u001b[33m56\u001b[39m, \u001b[33m57\u001b[39m, \u001b[33m58\u001b[39m, \u001b[33m59\u001b[39m',
-    ']',
-  ].join('\n');
+  const inlineNumbers = Array.from({ length: 60 }, (_, i) => `\u001b[33m${i}\u001b[39m`);
+  expected = `[ ${inlineNumbers.join(', ')} ]`;
 
   assert.strictEqual(out, expected);
 
@@ -4095,6 +4079,22 @@ ${error.stack.split('\n').slice(1).join('\n')}`,
   assert.strictEqual(util.inspect(obj, { breakLength: Infinity }), expected);
 }
 
+{
+  // Refs: https://github.com/nodejs/node/issues/60475
+  // `breakLength: Infinity` should format deeply nested objects on a single line
+  // regardless of depth limit or array size.
+  const obj = { a: { b: { c: { d: { e: 1 } } } } };
+  const expected = '{ a: { b: { c: { d: { e: 1 } } } } }';
+  assert.strictEqual(util.inspect(obj, { breakLength: Infinity, depth: Infinity }), expected);
+  assert.strictEqual(util.inspect(obj, { breakLength: Infinity, depth: null }), expected);
+  assert.strictEqual(util.inspect(obj, { breakLength: Infinity, depth: 10 }), expected);
+
+  const arr = Array.from({ length: 60 }, (_, i) => i);
+  const arrExpected = `[ ${arr.join(', ')} ]`;
+  assert.strictEqual(util.inspect(arr, { breakLength: Infinity, depth: Infinity }), arrExpected);
+  assert.strictEqual(util.inspect(arr, { breakLength: Infinity, depth: 2, compact: 3 }), arrExpected);
+}
+
 {
   class Class {
     get [Symbol.toStringTag]() {