[ruby/irb] Type based completion using Prism and RBS

(https://github.com/ruby/irb/pull/708)

* Add completor using prism and rbs

* Add TypeCompletion test

* Switchable completors: RegexpCompletor and TypeCompletion::Completor

* Add completion info to irb_info

* Complete reserved words

* Fix [*] (*) {**} and prism's change of KeywordParameterNode

* Fix require, frozen_string_literal

* Drop prism<=0.16.0 support

* Add Completor.last_completion_error for debug report

* Retrieve `self` and `Module.nesting` in more safe way

* Support BasicObject

* Handle lvar and ivar get exception correctly

* Skip ivar reference test of non-self object in ruby < 3.2

* BaseScope to RootScope, move method objects constant under Methods

* Remove unused Splat struct

* Drop deeply nested array/hash type calculation from actual object. Now, calculation depth is 1

* Refactor loading rbs in test, change preload_in_thread not to cache Thread object

* Use new option added in prism 0.17.1 to parse code with localvars

* Add Prism version check and warn when :type completor cannot be enabled

* build_type_completor should skip truffleruby (because endless method definition is not supported)

https://github.com/ruby/irb/commit/1048c7ed7a

1 files changed, 39 insertions, 2 deletions

diff --git a/lib/irb/context.rb b/lib/irb/context.rb
index a20510d73c..5dfe9d0d71 100644
--- a/lib/irb/context.rb
+++ b/lib/irb/context.rb
@@ -86,14 +86,14 @@ module IRB
         when nil
           if STDIN.tty? && IRB.conf[:PROMPT_MODE] != :INF_RUBY && !use_singleline?
             # Both of multiline mode and singleline mode aren't specified.
-            @io = RelineInputMethod.new
+            @io = RelineInputMethod.new(build_completor)
           else
             @io = nil
           end
         when false
           @io = nil
         when true
-          @io = RelineInputMethod.new
+          @io = RelineInputMethod.new(build_completor)
         end
         unless @io
           case use_singleline?
@@ -149,6 +149,43 @@ module IRB
       @command_aliases = IRB.conf[:COMMAND_ALIASES]
     end
 
+    private def build_completor
+      completor_type = IRB.conf[:COMPLETOR]
+      case completor_type
+      when :regexp
+        return RegexpCompletor.new
+      when :type
+        completor = build_type_completor
+        return completor if completor
+      else
+        warn "Invalid value for IRB.conf[:COMPLETOR]: #{completor_type}"
+      end
+      # Fallback to RegexpCompletor
+      RegexpCompletor.new
+    end
+
+    TYPE_COMPLETION_REQUIRED_PRISM_VERSION = '0.17.1'
+
+    private def build_type_completor
+      unless Gem::Version.new(RUBY_VERSION) >= Gem::Version.new('3.0.0') && RUBY_ENGINE != 'truffleruby'
+        warn 'TypeCompletion requires RUBY_VERSION >= 3.0.0'
+        return
+      end
+      begin
+        require 'prism'
+      rescue LoadError => e
+        warn "TypeCompletion requires Prism: #{e.message}"
+        return
+      end
+      unless Gem::Version.new(Prism::VERSION) >= Gem::Version.new(TYPE_COMPLETION_REQUIRED_PRISM_VERSION)
+        warn "TypeCompletion requires Prism::VERSION >= #{TYPE_COMPLETION_REQUIRED_PRISM_VERSION}"
+        return
+      end
+      require 'irb/type_completion/completor'
+      TypeCompletion::Types.preload_in_thread
+      TypeCompletion::Completor.new
+    end
+
     def save_history=(val)
       IRB.conf[:SAVE_HISTORY] = val
     end