beautifier · SarthakDudhe · May 3, 2026 · May 3, 2026 · May 3, 2026 · May 3, 2026
diff --git a/config_2010.json b/config_2010.json
@@ -0,0 +1,21 @@
+{
+  "indent_size": 4,
+  "indent_char": " ",
+  "max_preserve_newlines": 1,
+  "preserve_newlines": true,
+  "keep_array_indentation": true,
+  "break_chained_methods": false,
+  "indent_scripts": "normal",
+  "brace_style": "collapse",
+  "space_before_conditional": true,
+  "unescape_strings": false,
+  "jslint_happy": false,
+  "end_with_newline": false,
+  "wrap_line_length": 0,
+  "indent_inner_html": false,
+  "comma_first": true,
+  "e4x": true,
+  "indent_empty_lines": true,
+  "space_in_paren": true,
+  "indent_with_tabs": true
+}
diff --git a/input_2010.js b/input_2010.js
@@ -0,0 +1,5 @@
+a = [
+    1,
+    2,
+    3
+]
diff --git a/js/src/html/beautifier.js b/js/src/html/beautifier.js
@@ -375,9 +375,13 @@ Beautifier.prototype._handle_tag_close = function(printer, raw_token, last_tag_t
     printer.add_raw_token(raw_token);
   } else {
     if (last_tag_token.tag_start_char === '<') {
-      printer.set_space_before_token(raw_token.text[0] === '/', true); // space before />, no space before >
-      if (this._is_wrap_attributes_force_expand_multiline && last_tag_token.has_wrapped_attrs) {
+      if ((this._is_wrap_attributes_preserve || this._is_wrap_attributes_preserve_aligned) &&
+        printer.traverse_whitespace(raw_token)) {
+        // preserved newline or space
+      } else if (this._is_wrap_attributes_force_expand_multiline && last_tag_token.has_wrapped_attrs) {
         printer.print_newline(false);
+      } else {
+        printer.set_space_before_token(raw_token.text[0] === '/', true); // space before />, no space before >
       }
     }
     printer.print_token(raw_token);
@@ -750,7 +754,7 @@ Beautifier.prototype._set_tag_position = function(printer, raw_token, parser_tok
     }
 
     // Don't add a newline before elements that should remain where they are.
-    if (parser_token.tag_name === '!--' && last_token.type === TOKEN.TAG_CLOSE &&
+    if (parser_token.tag_name.indexOf('!--') === 0 && last_token.type === TOKEN.TAG_CLOSE &&
       last_tag_token.is_end_tag && parser_token.text.indexOf('\n') === -1) {
       //Do nothing. Leave comments on same line.
     } else {
@@ -816,7 +820,7 @@ Beautifier.prototype._do_optional_end_element = function(parser_token) {
   // are handled automatically by the beautifier.
   // It assumes parent or ancestor close tag closes all children.
   // https://www.w3.org/TR/html5/syntax.html#optional-tags
-  if (parser_token.is_empty_element || !parser_token.is_start_tag || !parser_token.parent) {
+  if (parser_token.is_empty_element || !parser_token.is_start_tag || !parser_token.parent || parser_token.tag_start_char !== '<') {
     return;
 
   }

diff --git a/js/src/javascript/beautifier.js b/js/src/javascript/beautifier.js
@@ -1122,7 +1122,7 @@ Beautifier.prototype.handle_comma = function(current_token) {
     if (this._flags.declaration_assignment) {
       this._flags.declaration_assignment = false;
       this.print_newline(false, true);
-    } else if (this._options.comma_first) {
+    } else if (this._options.comma_first && !(this._options.keep_array_indentation && is_array(this._flags.mode) && current_token.newlines)) {
       // for comma-first, we want to allow a newline before the comma
       // to turn into a newline after the comma, which we will fixup later
       this.allow_wrap_or_preserved_newline(current_token);
@@ -1136,7 +1136,7 @@ Beautifier.prototype.handle_comma = function(current_token) {
     if (!this._flags.inline_frame) {
       this.print_newline();
     }
-  } else if (this._options.comma_first) {
+  } else if (this._options.comma_first && !(this._options.keep_array_indentation && is_array(this._flags.mode) && current_token.newlines)) {
     // EXPR or DO_BLOCK
     // for comma-first, we want to allow a newline before the comma
     // to turn into a newline after the comma, which we will fixup later

diff --git a/output_1.js b/output_1.js
@@ -0,0 +1,5 @@
+a = [
+    1
+    , 2
+    , 3
+]
diff --git a/output_2.js b/output_2.js
@@ -0,0 +1,5 @@
+a = [
+    1
+    , 2
+    , 3
+]
diff --git a/output_3.js b/output_3.js
@@ -0,0 +1,5 @@
+a = [
+    1
+    , 2
+    , 3
+]
diff --git a/test/data/html/tests.js b/test/data/html/tests.js
@@ -4402,6 +4402,36 @@ exports.test_data = {
       ]
     }]
   }, {
-    name: "New Test Suite"
+    name: "Issue #1823",
+    description: "HTML comments without leading spaces should remain on the same line as the preceding closing tag.",
+    matrix: [{
+      options: [
+        { name: "inline_custom_elements", value: "false" }
+      ]
+    }],
+    tests: [{
+      fragment: true,
+      unchanged: '<button>Click here</button><!--comment-->'
+    }, {
+      fragment: true,
+      unchanged: '<button>Click here</button><!-- comment -->'
+    }]
+  }, {
+    name: "Issue #1707",
+    description: "wrap_attributes: 'preserve' should preserve newline before closing bracket",
+    matrix: [{
+      options: [
+        { name: "wrap_attributes", value: "'preserve'" }
+      ]
+    }],
+    tests: [{
+      fragment: true,
+      unchanged: [
+        '<div',
+        '    attr="val"',
+        '>',
+        '</div>'
+      ]
+    }]
   }]
 };
-Original file line number
+Diff line change
@@ -0,0 +1,5 @@
+    a = [
+,
+,
+    ]