add spec

spec/lib/completions/anthropic_message_processor_spec.rb

@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+describe DiscourseAi::Completions::AnthropicMessageProcessor do
+  it "correctly handles and combines partial thinking chunks into complete thinking objects" do
+    processor =
+      DiscourseAi::Completions::AnthropicMessageProcessor.new(
+        streaming_mode: true,
+        partial_tool_calls: false,
+        output_thinking: true,
+      )
+
+    # Simulate streaming thinking output in multiple chunks
+    result1 =
+      processor.process_streamed_message(
+        { type: "content_block_start", content_block: { type: "thinking", thinking: "" } },
+      )
+
+    result2 =
+      processor.process_streamed_message(
+        {
+          type: "content_block_delta",
+          delta: {
+            type: "thinking_delta",
+            thinking: "First part of thinking",
+          },
+        },
+      )
+
+    result3 =
+      processor.process_streamed_message(
+        {
+          type: "content_block_delta",
+          delta: {
+            type: "thinking_delta",
+            thinking: " and second part",
+          },
+        },
+      )
+
+    _result4 =
+      processor.process_streamed_message(
+        {
+          type: "content_block_delta",
+          delta: {
+            type: "signature_delta",
+            signature: "thinking-sig-123",
+          },
+        },
+      )
+
+    # Finish the thinking block
+    final_result = processor.process_streamed_message({ type: "content_block_stop" })
+
+    # Verify the partial thinking chunks
+    expect(result1).to be_a(DiscourseAi::Completions::Thinking)
+    expect(result1.message).to eq("")
+    expect(result1.partial?).to eq(true)
+
+    expect(result2).to be_a(DiscourseAi::Completions::Thinking)
+    expect(result2.message).to eq("First part of thinking")
+    expect(result2.partial?).to eq(true)
+
+    expect(result3).to be_a(DiscourseAi::Completions::Thinking)
+    expect(result3.message).to eq(" and second part")
+    expect(result3.partial?).to eq(true)
+
+    # Verify the final complete thinking object
+    expect(final_result).to be_a(DiscourseAi::Completions::Thinking)
+    expect(final_result.message).to eq("First part of thinking and second part")
+    expect(final_result.signature).to eq("thinking-sig-123")
+    expect(final_result.partial?).to eq(false)
+  end
+end