fail on uninstrumented methods

Author: chris-olszewski

temporalio/test/support/sig_applicator.rb

@@ -65,10 +65,7 @@ def apply_all!
 
       warn "SigApplicator: applied #{applied} runtime type signatures (#{skipped} skipped)"
 
-      return if errors.empty?
-
-      warn "SigApplicator: #{errors.size} methods could not be instrumented:"
-      errors.each { |e| warn "  #{e}" }
+      raise_instrumentation_errors!(errors)
     end
 
     def record_type_error(message)
@@ -142,6 +139,14 @@ def register_summary_hook!
       Object.const_set(:ZZZSigApplicatorTest, klass)
     end
 
+    def raise_instrumentation_errors!(errors)
+      return if errors.empty?
+
+      summary = +"SigApplicator: #{errors.size} methods could not be instrumented:\n"
+      errors.each { |error| summary << "  #{error}\n" }
+      raise summary.chomp
+    end
+
     def apply_scope(node, errors)
       return [0, 0] unless node.respond_to?(:nodes)
 

temporalio/test/support/sig_applicator_test.rb

@@ -124,6 +124,36 @@ def foo; end
       refute skip_method?(original, method_node, :foo)
     end
 
+    def test_apply_all_raises_when_signature_cannot_be_instrumented
+      test_class = Class.new do
+        extend T::Sig
+
+        def self.foo(value); end
+      end
+      Support.const_set(:SigApplicatorApplyAllTest, test_class)
+
+      tree = RBI::Parser.parse_string(<<~RBI)
+        class Support::SigApplicatorApplyAllTest
+          sig { params(other: String).void }
+          def self.foo(value); end
+        end
+      RBI
+
+      parser = RBI::Parser.singleton_class
+      original_parse_file = RBI::Parser.method(:parse_file)
+      parser.send(:define_method, :parse_file) { |_path| tree }
+
+      Object.send(:remove_const, :ZZZSigApplicatorTest) if Object.const_defined?(:ZZZSigApplicatorTest)
+
+      error = assert_raises(RuntimeError) { SigApplicator.apply_all! }
+      assert_includes error.message, 'SigApplicator: 1 methods could not be instrumented:'
+      assert_includes error.message, 'Support::SigApplicatorApplyAllTest.foo:'
+    ensure
+      parser.send(:define_method, :parse_file, original_parse_file)
+      Support.send(:remove_const, :SigApplicatorApplyAllTest) if Support.const_defined?(:SigApplicatorApplyAllTest, false)
+      Object.send(:remove_const, :ZZZSigApplicatorTest) if Object.const_defined?(:ZZZSigApplicatorTest)
+    end
+
     private
 
     def parse_method(source)