From e424be03c6245f29f443dec647c4d10fbd3c1d4c Mon Sep 17 00:00:00 2001
From: Earlopain <14981592+Earlopain@users.noreply.github.com>
Date: Fri, 8 Mar 2024 16:23:32 +0100
Subject: [PATCH] Improve error message when passing wrong `parser_engine` and
 accept strings

---
 lib/rubocop/ast/processed_source.rb       |  5 +++--
 spec/rubocop/ast/processed_source_spec.rb | 23 +++++++++++++++++------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/lib/rubocop/ast/processed_source.rb b/lib/rubocop/ast/processed_source.rb
index fb18c0310..116f40c56 100644
--- a/lib/rubocop/ast/processed_source.rb
+++ b/lib/rubocop/ast/processed_source.rb
@@ -27,9 +27,10 @@ def self.from_file(path, ruby_version, parser_engine: :parser_whitequark)
       end
 
       def initialize(source, ruby_version, path = nil, parser_engine: :parser_whitequark)
+        parser_engine = parser_engine.to_sym
         unless PARSER_ENGINES.include?(parser_engine)
-          raise ArgumentError, 'The keyword argument `parser_engine` accepts ' \
-                               "`parser` or `parser_prism`, but `#{parser_engine}` was passed."
+          raise ArgumentError, 'The keyword argument `parser_engine` accepts `parser_whitequark` ' \
+                               "or `parser_prism`, but `#{parser_engine}` was passed."
         end
 
         # Defaults source encoding to UTF-8, regardless of the encoding it has
diff --git a/spec/rubocop/ast/processed_source_spec.rb b/spec/rubocop/ast/processed_source_spec.rb
index 00780b220..cd0e1d4ac 100644
--- a/spec/rubocop/ast/processed_source_spec.rb
+++ b/spec/rubocop/ast/processed_source_spec.rb
@@ -28,16 +28,27 @@ def some_method
       end
     end
 
-    context 'when using invalid `parser_engine` argument' do
-      let(:parser_engine) { :unknown_parser_engine }
-
-      it 'raises a Errno::ENOENT when the file does not exist' do
+    shared_examples 'invalid parser_engine' do
+      it 'raises ArgumentError' do
         expect { processed_source }.to raise_error(ArgumentError) do |e|
-          expect(e.message).to eq 'The keyword argument `parser_engine` accepts `parser` or ' \
-                                  '`parser_prism`, but `unknown_parser_engine` was passed.'
+          expected =  'The keyword argument `parser_engine` accepts `parser_whitequark` ' \
+                      "or `parser_prism`, but `#{parser_engine}` was passed."
+          expect(e.message).to eq(expected)
         end
       end
     end
+
+    context 'when using an invalid `parser_engine` symbol argument' do
+      let(:parser_engine) { :unknown_parser_engine }
+
+      it_behaves_like 'invalid parser_engine'
+    end
+
+    context 'when using an invalid `parser_engine` string argument' do
+      let(:parser_engine) { 'unknown_parser_engine' }
+
+      it_behaves_like 'invalid parser_engine'
+    end
   end
 
   describe '.from_file' do