[ruby/prism] Prism::StringQuery

Introduce StringQuery to provide methods to access some metadata
about the Ruby lexer.

https://github.com/ruby/prism/commit/d3f55b67b9

1 files changed, 60 insertions, 0 deletions

diff --git a/test/prism/ruby/string_query_test.rb b/test/prism/ruby/string_query_test.rb
new file mode 100644
index 0000000000..aa50c10ff3
--- /dev/null
+++ b/test/prism/ruby/string_query_test.rb
@@ -0,0 +1,60 @@
+# frozen_string_literal: true
+
+require_relative "../test_helper"
+
+module Prism
+  class StringQueryTest < TestCase
+    def test_local?
+      assert_predicate StringQuery.new("a"), :local?
+      assert_predicate StringQuery.new("a1"), :local?
+      assert_predicate StringQuery.new("self"), :local?
+
+      assert_predicate StringQuery.new("_a"), :local?
+      assert_predicate StringQuery.new("_1"), :local?
+
+      assert_predicate StringQuery.new("😀"), :local?
+      assert_predicate StringQuery.new("ア".encode("Windows-31J")), :local?
+
+      refute_predicate StringQuery.new("1"), :local?
+      refute_predicate StringQuery.new("A"), :local?
+    end
+
+    def test_constant?
+      assert_predicate StringQuery.new("A"), :constant?
+      assert_predicate StringQuery.new("A1"), :constant?
+      assert_predicate StringQuery.new("A_B"), :constant?
+      assert_predicate StringQuery.new("BEGIN"), :constant?
+
+      assert_predicate StringQuery.new("À"), :constant?
+      assert_predicate StringQuery.new("A".encode("US-ASCII")), :constant?
+
+      refute_predicate StringQuery.new("a"), :constant?
+      refute_predicate StringQuery.new("1"), :constant?
+    end
+
+    def test_method_name?
+      assert_predicate StringQuery.new("a"), :method_name?
+      assert_predicate StringQuery.new("A"), :method_name?
+      assert_predicate StringQuery.new("__FILE__"), :method_name?
+
+      assert_predicate StringQuery.new("a?"), :method_name?
+      assert_predicate StringQuery.new("a!"), :method_name?
+      assert_predicate StringQuery.new("a="), :method_name?
+
+      assert_predicate StringQuery.new("+"), :method_name?
+      assert_predicate StringQuery.new("<<"), :method_name?
+      assert_predicate StringQuery.new("==="), :method_name?
+
+      assert_predicate StringQuery.new("_0"), :method_name?
+
+      refute_predicate StringQuery.new("1"), :method_name?
+      refute_predicate StringQuery.new("_1"), :method_name?
+    end
+
+    def test_invalid_encoding
+      assert_raise ArgumentError do
+        StringQuery.new("A".encode("UTF-16LE")).local?
+      end
+    end
+  end
+end