From ebeab75f5862a7844558d7526db95ed1f720041b Mon Sep 17 00:00:00 2001
From: ydah <13041216+ydah@users.noreply.github.com>
Date: Thu, 27 Jul 2023 21:38:03 +0900
Subject: [PATCH] Fix to not delete anything other than comments.

---
 lib/slim/embedded/minify/javascript.rb  | 37 +++++++++++++++--
 lib/slim/embedded/minify/tag.rb         | 55 +++++++++++++++++++++++--
 test/embedded/minify/javascript_test.rb | 12 +++---
 test/embedded/minify/tag_test.rb        |  3 +-
 4 files changed, 93 insertions(+), 14 deletions(-)

diff --git a/lib/slim/embedded/minify/javascript.rb b/lib/slim/embedded/minify/javascript.rb
index 5247b95..1241964 100644
--- a/lib/slim/embedded/minify/javascript.rb
+++ b/lib/slim/embedded/minify/javascript.rb
@@ -10,12 +10,41 @@ def on_slim_embedded(engine, body, attrs)
           minified_body = minify(body)
           super(engine, minified_body, attrs)
         end
+        def remove_comments!(line)
+          need_deletion = false
+          need_deletion_all = false
+          inside_char = nil
+          line[-1] = line.last.chars.each_with_index.map do |char, index|
+            next if need_deletion_all
 
-        private
+            if char == '/' && next_char(line, index) == '*' && inside_char.nil?
+              if remaining_string_range(line, index).match?(/\*\//)
+                need_deletion = true
+                next
+              end
+            elsif char == '/' && prev_char(line, index) == '*' && inside_char.nil? && need_deletion
+              need_deletion = false
+              next
+            elsif char == '/' && next_char(line, index) == '/' && inside_char.nil? && !need_deletion
+              need_deletion_all = true
+              next
+            elsif char == '"' && !need_deletion
+              if inside_char == '"'
+                inside_char = nil
+                next char
+              end
 
-        def remove_comments!(line)
-          line.last.gsub!(/((?<!['"])\/\*.*?\*\/(?<!['"]))/, '')
-          line.last.gsub!(/((?<!['"])\/\/.*)/, '')
+              inside_char = '"' if inside_char.nil?
+            elsif char == "'" && !need_deletion
+              if inside_char == "'"
+                inside_char = nil
+                next char
+              end
+
+              inside_char = "'" if inside_char.nil?
+            end
+            char unless need_deletion
+          end&.compact&.join
         end
       end
     end
diff --git a/lib/slim/embedded/minify/tag.rb b/lib/slim/embedded/minify/tag.rb
index b8b5b7d..c7a51d1 100644
--- a/lib/slim/embedded/minify/tag.rb
+++ b/lib/slim/embedded/minify/tag.rb
@@ -16,26 +16,73 @@ def minify(body)
           body.map do |line|
             if line.instance_of?(Array) && line.first == :slim
               remove_comments!(line)
-              remove_whitespace!(line)
+              next if line.last.nil?
 
+              remove_whitespace!(line)
               stripped_quotes = stripped_quotes(line)
-              if stripped_quotes.match?(%r{/\*})
+              if stripped_quotes.match?(%r{/\*}) && !multiline_comment
                 multiline_comment = true
-                line.last.sub!(/(?<!['"])\/\*.*$/, '')
+                line[-1] = line.last.reverse.sub(/.*?\*\//, '').reverse
               elsif multiline_comment
                 next unless stripped_quotes.match?(%r{\*/})
 
                 multiline_comment = false
                 line.last.sub!(/.*\*\/(?<!['"])/, '')
               end
+              if stripped_quotes.match?(%r{/\*}) && !multiline_comment
+                multiline_comment = true
+                line[-1] = line.last.reverse.sub(/.*?\*\//, '').reverse
+              end
               next if empty_line?(line)
             end
             line
           end.compact
         end
 
+        def minify_multiple_comments!(line)
+        end
+
         def remove_comments!(line)
-          line.last.gsub!(/((?<!['"])\/\*.*?\*\/(?<!['"]))/, '')
+          need_deletion = false
+          inside_char = nil
+          line[-1] = line.last.chars.each_with_index.map do |char, index|
+            if char == '/' && next_char(line, index) == '*' && inside_char.nil?
+              if remaining_string_range(line, index).match?(/\*\//)
+                need_deletion = true
+                next
+              end
+            elsif char == '/' && prev_char(line, index) == '*' && inside_char.nil? && need_deletion
+              need_deletion = false
+              next
+            elsif char == '"' && !need_deletion
+              if inside_char == '"'
+                inside_char = nil
+                next char
+              end
+
+              inside_char = '"' if inside_char.nil?
+            elsif char == "'" && !need_deletion
+              if inside_char == "'"
+                inside_char = nil
+                next char
+              end
+
+              inside_char = "'" if inside_char.nil?
+            end
+            char unless need_deletion
+          end&.compact&.join
+        end
+
+        def remaining_string_range(line, index)
+          line.last[index..-1]
+        end
+
+        def prev_char(line, index)
+          line.last[index - 1]
+        end
+
+        def next_char(line, index)
+          line.last[index + 1]
         end
 
         def remove_whitespace!(line)
diff --git a/test/embedded/minify/javascript_test.rb b/test/embedded/minify/javascript_test.rb
index 0bf8aa7..1e5c7eb 100644
--- a/test/embedded/minify/javascript_test.rb
+++ b/test/embedded/minify/javascript_test.rb
@@ -47,12 +47,15 @@ def test_render_with_javascript_and_multiline_comment
 
 
         comment */alert('hello')
+        /* comment */alert("argument /* argument")/* comment
+        comment */
       p Hi
     SLIM
     assert_html <<~HTML.chomp, source
       <script>
       $(function() {})
-      alert('hello')</script><p>Hi</p>
+      alert('hello')
+      alert("argument /* argument")</script><p>Hi</p>
     HTML
   end
 
@@ -63,18 +66,17 @@ def test_render_with_javascript_and_singleline_comment
         $(function() {});
           /* ... * comment / */
 
+        /* comment */"/* string */"/* comment */
         /* ... * comment / */alert("/* argument */")/*... * comment /*/
         /* comment */alert("/* argument */")/*comment*/
-        /* comment */alert("/* argument")/* comment
-        comment */
       p Hi
     SLIM
     assert_html <<~HTML.chomp, source
       <script>
       $(function() {});
+      "/* string */"
       alert("/* argument */")
-      alert("/* argument */")
-      alert("/* argument")</script><p>Hi</p>
+      alert("/* argument */")</script><p>Hi</p>
     HTML
   end
 
diff --git a/test/embedded/minify/tag_test.rb b/test/embedded/minify/tag_test.rb
index af3ef44..41b2516 100644
--- a/test/embedded/minify/tag_test.rb
+++ b/test/embedded/minify/tag_test.rb
@@ -63,7 +63,8 @@ def test_render_with_css_and_multiple_comment
         */
         h1 {
           color: blue;/* multiline
-          comment */  font-size: 12px;
+          comment */  font-size: 12px;/* comment
+          after */
         }
     SLIM
     assert_html <<~HTML.chomp, source