bug fix for LLM function calling

Signed-off-by: Mandana Vaziri <[email protected]>

Author: vazirim

src/pdl/pdl_llms.py

@@ -162,7 +162,10 @@ def generate_text(
         )
         msg = response.choices[0].message  # pyright: ignore
         if msg.content is None:
-            assert False, "TODO"  # XXX TODO XXX
+            return {
+                "role": msg.role,
+                "content": "",
+            }, response.json()  # pyright: ignore
         return {
             "role": msg.role,
             "content": msg.content,
@@ -190,6 +193,6 @@ def generate_text_stream(
             result.append(chunk.json())  # pyright: ignore
             msg = chunk.choices[0].delta  # pyright: ignore
             if msg.content is None:
-                break
+                continue
             yield {"role": msg.role, "content": msg.content}
         return result

tests/results/examples/react/demo.result

@@ -35,6 +35,8 @@ Act: {"name": "Search", "arguments": {"topic": "Henry Hudson"}}
 Obs: Henry Hudson (c. 1565 – disappeared 23 June 1611) was an English sea explorer and navigator during the early 17th century, best known for his explorations of present-day Canada and parts of the Northeastern United States.
 In 1607 and 1608, Hudson made two attempts on behalf of English merchants to find a rumoured Northeast Passage to Cathay via a route above the Arctic Circle. In 1609, he landed in North America on behalf of the Dutch East India Company and explored the region around the modern New York metropolitan area. Looking for a Northwest Passage to Asia on his ship Halve Maen ("Half Moon"), he sailed up the Hudson River, which was later named after him, and thereby laid the foundation for Dutch colonization of the region. His contributions to the exploration of the New World were significant and lasting. His voyages helped to establish European contact with the native peoples of North America and contributed to the development of trade and commerce. 
 On his final expedition, while still searching for the Northwest Passage, Hudson became the first European to see Hudson Strait and the immense Hudson Bay. In 1611, after wintering on the shore of James Bay, Hudson wanted to press on to the west, but most of his crew mutinied. The mutineers cast Hudson, his son, and six others adrift; what then happened to the Hudsons and their companions is unknown.
+
+
 Tho: Henry Hudson was born around 1565. To find out how many years ago that was, I need to subtract his birth year from the current year, which is 2024.
 Act: {"name": "Calc", "arguments": {"expr": "2024 - 1565"}}
 Obs: 459