Automatically update the latest version in the README

Author: eregon

README.md

@@ -15,7 +15,7 @@ This action currently supports these versions of MRI, JRuby and TruffleRuby:
 | Interpreter | Versions |
 | ----------- | -------- |
 | `ruby` | 1.9.3, 2.0.0, 2.1.9, 2.2, all versions from 2.3.0 until 3.1.0, head, debug, mingw, mswin |
-| `jruby` | 9.1.17.0 - 9.3.2.0, head |
+| `jruby` | 9.1.17.0 - 9.3.3.0, head |
 | `truffleruby` | 19.3.0 - 21.3.0, head |
 | `truffleruby+graalvm` | 21.2.0 - 21.3.0, head |
 

new-version.rb

@@ -9,6 +9,7 @@
 
 raise unless version[MATCH]
 
+# Update ruby-builder-versions.json
 file = "#{__dir__}/ruby-builder-versions.json"
 lines = File.readlines(file, chomp: true)
 
@@ -26,9 +27,23 @@
 }
 
 if release_line
-  release_line << " #{version.inspect},"
+  append = " #{version.inspect},"
+  release_line << append unless release_line.end_with?(append)
 else
   lines.insert to+1, "    #{version.inspect},"
 end
 
 File.write(file, lines.join("\n") + "\n")
+
+# Update README.md
+file = "#{__dir__}/README.md"
+lines = File.readlines(file)
+engine_line = lines.find { |line| line.start_with?("| `#{engine}`") }
+engine_line.sub!(/(.+ (?:-|until)) (\d+(?:\.\d+)+)/) do
+  if Gem::Version.new(version) > Gem::Version.new($2)
+    "#{$1} #{version}"
+  else
+    $&
+  end
+end
+File.write(file, lines.join)