1 files changed, 101 insertions, 0 deletions
diff --git a/test/prism/errors_test.rb b/test/prism/errors_test.rb
new file mode 100644
index 0000000000..f46cb942a2
--- /dev/null
+++ b/test/prism/errors_test.rb
@@ -0,0 +1,101 @@
+# frozen_string_literal: true
+
+require_relative "test_helper"
+
+module Prism
+  class ErrorsTest < TestCase
+    base = File.expand_path("errors", __dir__)
+    filepaths = Dir["*.txt", base: base]
+
+    if RUBY_VERSION < "3.0"
+      filepaths -= [
+        "cannot_assign_to_a_reserved_numbered_parameter.txt",
+        "writing_numbered_parameter.txt",
+        "targeting_numbered_parameter.txt",
+        "defining_numbered_parameter.txt",
+        "defining_numbered_parameter_2.txt",
+        "numbered_parameters_in_block_arguments.txt"
+      ]
+    end
+
+    if RUBY_VERSION < "3.4"
+      filepaths -= ["it_with_ordinary_parameter.txt"]
+    end
+
+    if RUBY_VERSION < "3.4" || RUBY_RELEASE_DATE < "2024-07-24"
+      filepaths -= ["dont_allow_return_inside_sclass_body.txt"]
+    end
+
+    filepaths.each do |filepath|
+      define_method(:"test_#{File.basename(filepath, ".txt")}") do
+        assert_errors(File.join(base, filepath))
+      end
+    end
+
+    def test_embdoc_ending
+      source = <<~RUBY
+        =begin\n=end
+        =begin\n=end\0
+        =begin\n=end\C-d
+        =begin\n=end\C-z
+      RUBY
+
+      source.each_line do |line|
+        assert_valid_syntax(source)
+        assert_predicate Prism.parse(source), :success?
+      end
+    end
+
+    def test_unterminated_string_closing
+      statement = Prism.parse_statement("'hello")
+      assert_equal statement.unescaped, "hello"
+      assert_empty statement.closing
+    end
+
+    def test_unterminated_interpolated_string_closing
+      statement = Prism.parse_statement('"hello')
+      assert_equal statement.unescaped, "hello"
+      assert_empty statement.closing
+    end
+
+    def test_unterminated_empty_string_closing
+      statement = Prism.parse_statement('"')
+      assert_empty statement.unescaped
+      assert_empty statement.closing
+    end
+
+    def test_invalid_message_name
+      assert_equal :"", Prism.parse_statement("+.@foo,+=foo").write_name
+    end
+
+    def test_circular_parameters
+      source = <<~RUBY
+        def foo(bar = bar) = 42
+        def foo(bar: bar) = 42
+        proc { |foo = foo| }
+        proc { |foo: foo| }
+      RUBY
+
+      source.each_line do |line|
+        assert_predicate Prism.parse(line, version: "3.3.0"), :failure?
+        assert_predicate Prism.parse(line), :success?
+      end
+    end
+
+    private
+
+    def assert_errors(filepath)
+      expected = File.read(filepath, binmode: true, external_encoding: Encoding::UTF_8)
+
+      source = expected.lines.grep_v(/^\s*\^/).join.gsub(/\n*\z/, "")
+      refute_valid_syntax(source)
+
+      result = Prism.parse(source)
+      errors = result.errors
+      refute_empty errors, "Expected errors in #{filepath}"
+
+      actual = result.errors_format
+      assert_equal expected, actual, "Expected errors to match for #{filepath}"
+    end
+  end
+end