util: treat format arguments equally

Two changes here which bring us closer to the console standard:

- Arguments to `util.format` are no longer formatted differently
  depending on their order, with format strings being an exception.
- Format specifier formatting is now only triggered if the string
  actually contains a format string.

Under the hood, we now use a single shared function to format the given
arguments which will make the code easier to read and modify.

PR-URL: https://github.com/nodejs/node/pull/23162
Fixes: https://github.com/nodejs/node/issues/23137
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Refael Ackermann <refack@gmail.com>

1 files changed, 16 insertions, 0 deletions

diff --git a/test/parallel/test-util-format.js b/test/parallel/test-util-format.js
index 0c4ba82fec..2ca8e0857f 100644
--- a/test/parallel/test-util-format.js
+++ b/test/parallel/test-util-format.js
@@ -273,6 +273,10 @@ assert.strictEqual(util.format('percent: %d%, fraction: %d', 10, 0.1),
                    'percent: 10%, fraction: 0.1');
 assert.strictEqual(util.format('abc%', 1), 'abc% 1');
 
+// Additional arguments after format specifiers
+assert.strictEqual(util.format('%i', 1, 'number'), '1 number');
+assert.strictEqual(util.format('%i', 1, () => {}), '1 [Function]');
+
 {
   const o = {};
   o.o = o;
@@ -315,3 +319,15 @@ function BadCustomError(msg) {
 util.inherits(BadCustomError, Error);
 assert.strictEqual(util.format(new BadCustomError('foo')),
                    '[BadCustomError: foo]');
+
+// The format of arguments should not depend on type of the first argument
+assert.strictEqual(util.format('1', '1'), '1 1');
+assert.strictEqual(util.format(1, '1'), '1 1');
+assert.strictEqual(util.format('1', 1), '1 1');
+assert.strictEqual(util.format(1, 1), '1 1');
+assert.strictEqual(util.format('1', () => {}), '1 [Function]');
+assert.strictEqual(util.format(1, () => {}), '1 [Function]');
+assert.strictEqual(util.format('1', "'"), "1 '");
+assert.strictEqual(util.format(1, "'"), "1 '");
+assert.strictEqual(util.format('1', 'number'), '1 number');
+assert.strictEqual(util.format(1, 'number'), '1 number');