Merge pull request #378 from dry-rb/reject-string-keys

Reject non-symbol keys in schemas

lib/dry/types/errors.rb

@@ -2,7 +2,7 @@
 
 module Dry
   module Types
-    extend Dry::Core::ClassAttributes
+    extend ::Dry::Core::ClassAttributes
 
     # @!attribute [r] namespace
     #   @return [Container{String => Nominal}]
@@ -12,7 +12,7 @@ module Types
 
     # Base class for coercion errors raise by dry-types
     #
-    class CoercionError < StandardError
+    class CoercionError < ::StandardError
       # @api private
       def self.handle(exception, meta: Undefined)
         if block_given?
@@ -34,7 +34,7 @@ def self.handle(exception, meta: Undefined)
       # @api private
       def initialize(message, meta: Undefined, backtrace: Undefined)
         unless message.is_a?(::String)
-          raise ArgumentError, "message must be a string, #{message.class} given"
+          raise ::ArgumentError, "message must be a string, #{message.class} given"
         end
 
         super(message)
@@ -74,9 +74,9 @@ def initialize(key, value, result)
       end
     end
 
-    MapError = Class.new(CoercionError)
+    MapError = ::Class.new(CoercionError)
 
-    SchemaKeyError = Class.new(CoercionError)
+    SchemaKeyError = ::Class.new(CoercionError)
     private_constant(:SchemaKeyError)
 
     class MissingKeyError < SchemaKeyError

lib/dry/types/schema/key.rb

@@ -31,6 +31,10 @@ def initialize(type, name, required: Undefined, **options)
             type.meta.fetch(:required) { !type.meta.fetch(:omittable, false) }
           end
 
+          unless name.is_a?(::Symbol)
+            raise ArgumentError, "Schemas can only contain symbol keys, #{name.inspect} given"
+          end
+
           super(type, name, required: required, **options)
           @name = name
         end

spec/dry/types/errors_spec.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+RSpec.describe 'dry types errors' do
+  describe Dry::Types::CoercionError do
+    it 'requires a string message' do
+      expect {
+        described_class.new(:invalid)
+      }.to raise_error(ArgumentError, /message must be a string/)
+    end
+  end
+end

spec/dry/types/hash_spec.rb

@@ -73,4 +73,18 @@
       specify { expect(type.transform_types?).to be(true) }
     end
   end
+
+  describe '#schema' do
+    let(:hash) { Dry::Types['hash'] }
+
+    it 'accepts only symbol keys' do
+      ['string_key', 42, Object.new, {}, []].each do |invalid_key|
+        expect {
+          hash.schema(valid: 'symbol', invalid_key => 'integer')
+        }.to raise_error(
+          ArgumentError, /Schemas can only contain symbol keys/
+        )
+      end
+    end
+  end
 end

spec/dry/types/schema_spec.rb

@@ -375,6 +375,16 @@ def self.meta
         string = Dry::Types['coercible.string'].meta(transformed: true)
         expect(extended.key(:city)).to eql(Dry::Types::Schema::Key.new(string, :city))
       end
+
+      it 'accepts only symbol keys' do
+        ['string_key', 42, Object.new, {}, []].each do |invalid_key|
+          expect {
+            hash.schema(valid: 'symbol', invalid_key => 'integer')
+          }.to raise_error(
+            ArgumentError, /Schemas can only contain symbol keys/
+          )
+        end
+      end
     end
 
     describe 'keys ending with question mark' do