util: change inspect compact and breakLength default

This changes the `compact` default from `true` to `3`. That mode
changes arrays to be grouped together, it alignes multiple small
entries on a single line in similar to `compact` true but only for
the most inner three depth levels and the closing brackets are
always on the same indentation as the openeing of the object instead
of at the same line as another property.

Big strings will be naturally broken into multiple lines instead of
having one huge line that is not well readable.

The output size mainly stays the same that way while it will be
smaller in case of big arrays.

Increasing the `breakLength` to 80 adjusts for most terminals that
support at least 80 characters in a single line and improves the
general output that way. A lot of calculations use the `breakLength`
to determine the concrete behavior.

PR-URL: #27109
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Minwoo Jung <minwoo@nodesource.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>

Author: BridgeAR

Diff for: doc/api/util.md

@@ -390,6 +390,10 @@ stream.write('With ES6');
 <!-- YAML
 added: v0.3.0
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/27109
+    description: The `compact` options default is changed to `3` and the
+                 `breakLength` options default is changed to `80`.
   - version: v11.11.0
     pr-url: https://github.com/nodejs/node/pull/26269
     description: The `compact` option accepts numbers for a new output mode.
@@ -463,16 +467,17 @@ changes:
     [`TypedArray`][], [`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`.
-  * `breakLength` {integer} The length at which an object's keys are split
-    across multiple lines. Set to `Infinity` to format an object as a single
-    line. **Default:** `60` for legacy compatibility.
+  * `breakLength` {integer} The length at which input values are split across
+    multiple lines. Set to `Infinity` to format the input as a single line
+    (in combination with `compact` set to `true` or any number >= `1`).
+    **Default:** `80`.
   * `compact` {boolean|integer} Setting this to `false` causes each object key
     to be displayed on a new line. It will also add new lines to text that is
     longer than `breakLength`. If set to a number, the most `n` inner elements
     are united on a single line as long as all properties fit into
     `breakLength`. Short array elements are also grouped together. Note that no
     text will be reduced below 16 characters, no matter the `breakLength` size.
-    For more information, see the example below. **Default:** `true`.
+    For more information, see the example below. **Default:** `3`.
   * `sorted` {boolean|Function} If set to `true` or a function, all properties
     of an object, and `Set` and `Map` entries are sorted in the resulting
     string. If set to `true` the [default sort][] is used. If set to a function,

Diff for: lib/internal/util/inspect.js

@@ -95,8 +95,8 @@ const inspectDefaultOptions = Object.seal({
   customInspect: true,
   showProxy: false,
   maxArrayLength: 100,
-  breakLength: 60,
-  compact: true,
+  breakLength: 80,
+  compact: 3,
   sorted: false,
   getters: false
 });

Diff for: test/parallel/test-console-group.js

@@ -122,11 +122,13 @@ function teardown() {
   const expectedOut = 'not indented\n' +
                       '  indented\n' +
                       '  also indented\n' +
-                      "  { also: 'a',\n" +
+                      '  {\n' +
+                      "    also: 'a',\n" +
                       "    multiline: 'object',\n" +
                       "    should: 'be',\n" +
                       "    indented: 'properly',\n" +
-                      "    kthx: 'bai' }\n";
+                      "    kthx: 'bai'\n" +
+                      '  }\n';
   const expectedErr = '';
 
   c.log('not indented');

Diff for: test/parallel/test-console.js

@@ -234,11 +234,11 @@ for (const expected of expectedStrings) {
 }
 
 assert.strictEqual(strings.shift(),
-                   "{ foo: 'bar',\n  [Symbol(nodejs.util.inspect.custom)]: " +
-                    '[Function: [nodejs.util.inspect.custom]] }\n');
+                   "{\n  foo: 'bar',\n  [Symbol(nodejs.util.inspect.custom)]:" +
+                    ' [Function: [nodejs.util.inspect.custom]]\n}\n');
 assert.strictEqual(strings.shift(),
-                   "{ foo: 'bar',\n  [Symbol(nodejs.util.inspect.custom)]: " +
-                    '[Function: [nodejs.util.inspect.custom]] }\n');
+                   "{\n  foo: 'bar',\n  [Symbol(nodejs.util.inspect.custom)]:" +
+                    ' [Function: [nodejs.util.inspect.custom]]\n}\n');
 assert.ok(strings.shift().includes('foo: [Object]'));
 assert.strictEqual(strings.shift().includes('baz'), false);
 assert.strictEqual(strings.shift(), 'inspect inspect\n');

Diff for: test/parallel/test-http2-stream-client.js

@@ -11,7 +11,7 @@ const server = http2.createServer();
 server.on('stream', common.mustCall((stream) => {
   assert.strictEqual(stream.aborted, false);
   const insp = util.inspect(stream);
-  assert.ok(/Http2Stream { id/.test(insp));
+  assert.ok(/Http2Stream {/.test(insp));
   assert.ok(/  state:/.test(insp));
   assert.ok(/  readableState:/.test(insp));
   assert.ok(/  writableState:/.test(insp));

Diff for: test/parallel/test-repl-pretty-stack.js

@@ -30,7 +30,7 @@ function run({ command, expected, ...extraREPLOptions }) {
 
 const tests = [
   {
-    // test .load for a file that throws
+    // Test .load for a file that throws.
     command: `.load ${fixtures.path('repl-pretty-stack.js')}`,
     expected: 'Thrown:\nError: Whoops!\n    at repl:9:24\n' +
               '    at d (repl:12:3)\n    at c (repl:9:3)\n' +
@@ -48,20 +48,20 @@ const tests = [
   {
     command: '(() => { const err = Error(\'Whoops!\'); ' +
              'err.foo = \'bar\'; throw err; })()',
-    expected: 'Thrown:\n{ Error: Whoops!\n    at repl:1:22\n  foo: \'bar\' }\n',
+    expected: "Thrown:\nError: Whoops!\n    at repl:1:22 {\n  foo: 'bar'\n}\n",
   },
   {
     command: '(() => { const err = Error(\'Whoops!\'); ' +
              'err.foo = \'bar\'; throw err; })()',
-    expected: 'Thrown:\n{ Error: Whoops!\n    at repl:1:22\n  foo: ' +
-              "\u001b[32m'bar'\u001b[39m }\n",
+    expected: 'Thrown:\nError: Whoops!\n    at repl:1:22 {\n  foo: ' +
+              "\u001b[32m'bar'\u001b[39m\n}\n",
     useColors: true
   },
   {
     command: 'foo = bar;',
     expected: 'Thrown:\nReferenceError: bar is not defined\n'
   },
-  // test anonymous IIFE
+  // Test anonymous IIFE.
   {
     command: '(function() { throw new Error(\'Whoops!\'); })()',
     expected: 'Thrown:\nError: Whoops!\n    at repl:1:21\n'

Diff for: test/parallel/test-repl-underscore.js

@@ -179,12 +179,13 @@ function testError() {
 
       // The sync error, with individual property echoes
       'Thrown:',
-      /^{ Error: ENOENT: no such file or directory, scandir '.*nonexistent.*'/,
+      /^Error: ENOENT: no such file or directory, scandir '.*nonexistent\?'/,
       /Object\.readdirSync/,
       /^  errno: -(2|4058),$/,
       "  syscall: 'scandir',",
       "  code: 'ENOENT',",
-      "  path: '/nonexistent?' }",
+      "  path: '/nonexistent?'",
+      '}',
       "'ENOENT'",
       "'scandir'",
 

Diff for: test/parallel/test-repl.js

@@ -534,15 +534,16 @@ const errorTests = [
     send: 'require("internal/repl")',
     expect: [
       'Thrown:',
-      /^{ Error: Cannot find module 'internal\/repl'/,
+      /^Error: Cannot find module 'internal\/repl'/,
       /^Require stack:/,
       /^- <repl>/,
       /^    at .*/,
       /^    at .*/,
       /^    at .*/,
       /^    at .*/,
       "  code: 'MODULE_NOT_FOUND',",
-      "  requireStack: [ '<repl>' ] }"
+      "  requireStack: [ '<repl>' ]",
+      '}'
     ]
   },
   // REPL should handle quotes within regexp literal in multiline mode

Diff for: test/parallel/test-util-format.js

@@ -165,59 +165,74 @@ assert.strictEqual(util.format('%o', 42), '42');
 assert.strictEqual(util.format('%o', 'foo'), '\'foo\'');
 assert.strictEqual(
   util.format('%o', obj),
-  '{ foo: \'bar\',\n' +
+  '{\n' +
+  '  foo: \'bar\',\n' +
   '  foobar: 1,\n' +
-  '  func:\n' +
-  '   { [Function: func]\n' +
-  '     [length]: 0,\n' +
-  '     [name]: \'func\',\n' +
-  '     [prototype]: func { [constructor]: [Circular] } } }');
+  '  func: [Function: func] {\n' +
+  '    [length]: 0,\n' +
+  '    [name]: \'func\',\n' +
+  '    [prototype]: func { [constructor]: [Circular] }\n' +
+  '  }\n' +
+  '}');
 assert.strictEqual(
   util.format('%o', nestedObj2),
-  '{ foo: \'bar\',\n' +
+  '{\n' +
+  '  foo: \'bar\',\n' +
   '  foobar: 1,\n' +
-  '  func:\n' +
-  '   [ { a:\n' +
-  '        { [Function: a]\n' +
-  '          [length]: 0,\n' +
-  '          [name]: \'a\',\n' +
-  '          [prototype]: a { [constructor]: [Circular] } } },\n' +
-  '     [length]: 1 ] }');
+  '  func: [\n' +
+  '    {\n' +
+  '      a: [Function: a] {\n' +
+  '        [length]: 0,\n' +
+  '        [name]: \'a\',\n' +
+  '        [prototype]: a { [constructor]: [Circular] }\n' +
+  '      }\n' +
+  '    },\n' +
+  '    [length]: 1\n' +
+  '  ]\n' +
+  '}');
 assert.strictEqual(
   util.format('%o', nestedObj),
-  '{ foo: \'bar\',\n' +
-  '  foobar:\n' +
-  '   { foo: \'bar\',\n' +
-  '     func:\n' +
-  '      { [Function: func]\n' +
-  '        [length]: 0,\n' +
-  '        [name]: \'func\',\n' +
-  '        [prototype]: func { [constructor]: [Circular] } } } }');
+  '{\n' +
+  '  foo: \'bar\',\n' +
+  '  foobar: {\n' +
+  '    foo: \'bar\',\n' +
+  '    func: [Function: func] {\n' +
+  '      [length]: 0,\n' +
+  '      [name]: \'func\',\n' +
+  '      [prototype]: func { [constructor]: [Circular] }\n' +
+  '    }\n' +
+  '  }\n' +
+  '}');
 assert.strictEqual(
   util.format('%o %o', obj, obj),
-  '{ foo: \'bar\',\n' +
+  '{\n' +
+  '  foo: \'bar\',\n' +
   '  foobar: 1,\n' +
-  '  func:\n' +
-  '   { [Function: func]\n' +
-  '     [length]: 0,\n' +
-  '     [name]: \'func\',\n' +
-  '     [prototype]: func { [constructor]: [Circular] } } }' +
-  ' { foo: \'bar\',\n' +
+  '  func: [Function: func] {\n' +
+  '    [length]: 0,\n' +
+  '    [name]: \'func\',\n' +
+  '    [prototype]: func { [constructor]: [Circular] }\n' +
+  '  }\n' +
+  '} {\n' +
+  '  foo: \'bar\',\n' +
   '  foobar: 1,\n' +
-  '  func:\n' +
-  '   { [Function: func]\n' +
-  '     [length]: 0,\n' +
-  '     [name]: \'func\',\n' +
-  '     [prototype]: func { [constructor]: [Circular] } } }');
+  '  func: [Function: func] {\n' +
+  '    [length]: 0,\n' +
+  '    [name]: \'func\',\n' +
+  '    [prototype]: func { [constructor]: [Circular] }\n' +
+  '  }\n' +
+  '}');
 assert.strictEqual(
   util.format('%o %o', obj),
-  '{ foo: \'bar\',\n' +
+  '{\n' +
+  '  foo: \'bar\',\n' +
   '  foobar: 1,\n' +
-  '  func:\n' +
-  '   { [Function: func]\n' +
-  '     [length]: 0,\n' +
-  '     [name]: \'func\',\n' +
-  '     [prototype]: func { [constructor]: [Circular] } } } %o');
+  '  func: [Function: func] {\n' +
+  '    [length]: 0,\n' +
+  '    [name]: \'func\',\n' +
+  '    [prototype]: func { [constructor]: [Circular] }\n' +
+  '  }\n' +
+  '} %o');
 
 assert.strictEqual(util.format('%O'), '%O');
 assert.strictEqual(util.format('%O', 42), '42');

Diff for: test/parallel/test-util-inspect-proxy.js

@@ -51,7 +51,8 @@ assert.strictEqual(
   util.inspect(proxyObj, opts),
   'Proxy [\n' +
   '  [ 1, 2, 3 ],\n' +
-  '  { getPrototypeOf: [Function: getPrototypeOf],\n' +
+  '  {\n' +
+  '    getPrototypeOf: [Function: getPrototypeOf],\n' +
   '    setPrototypeOf: [Function: setPrototypeOf],\n' +
   '    isExtensible: [Function: isExtensible],\n' +
   '    preventExtensions: [Function: preventExtensions],\n' +
@@ -63,7 +64,9 @@ assert.strictEqual(
   '    deleteProperty: [Function: deleteProperty],\n' +
   '    ownKeys: [Function: ownKeys],\n' +
   '    apply: [Function: apply],\n' +
-  '    construct: [Function: construct] } ]'
+  '    construct: [Function: construct]\n' +
+  '  }\n' +
+  ']'
 );
 
 // Using getProxyDetails with non-proxy returns undefined
@@ -89,14 +92,18 @@ const expected3 = 'Proxy [ Proxy [ Proxy [ {}, {} ], {} ], Proxy [ {}, {} ] ]';
 const expected4 = 'Proxy [ Proxy [ {}, {} ], Proxy [ Proxy [ {}, {} ], {} ] ]';
 const expected5 = 'Proxy [\n  ' +
                   'Proxy [ Proxy [ Proxy [Array], {} ], Proxy [ {}, {} ] ],\n' +
-                  '  Proxy [ Proxy [ {}, {} ], Proxy [ Proxy [Array], {} ] ] ]';
+                  '  Proxy [ Proxy [ {}, {} ], Proxy [ Proxy [Array], {} ] ]' +
+                  '\n]';
 const expected6 = 'Proxy [\n' +
                   '  Proxy [\n' +
                   '    Proxy [ Proxy [Array], Proxy [Array] ],\n' +
-                  '    Proxy [ Proxy [Array], Proxy [Array] ] ],\n' +
+                  '    Proxy [ Proxy [Array], Proxy [Array] ]\n' +
+                  '  ],\n' +
                   '  Proxy [\n' +
                   '    Proxy [ Proxy [Array], Proxy [Array] ],\n' +
-                  '    Proxy [ Proxy [Array], Proxy [Array] ] ] ]';
+                  '    Proxy [ Proxy [Array], Proxy [Array] ]\n' +
+                  '  ]\n' +
+                  ']';
 assert.strictEqual(
   util.inspect(proxy1, { showProxy: true, depth: null }),
   expected1);