chore: import upstream snapshot with attribution

python/semantic_kernel/prompt_template/utils/jinja2_system_helpers.py

@@ -0,0 +1,85 @@
+# Copyright (c) Microsoft. All rights reserved.
+
+import logging
+import re
+from collections.abc import Callable
+from xml.etree.ElementTree import tostring  # nosec B405
+
+logger: logging.Logger = logging.getLogger(__name__)
+
+
+def _messages(chat_history):
+    from semantic_kernel.contents.chat_history import ChatHistory
+
+    if not isinstance(chat_history, ChatHistory):
+        return ""
+    return chat_history.to_prompt()
+
+
+def _message_to_prompt(context):
+    from semantic_kernel.contents.chat_message_content import ChatMessageContent
+
+    if isinstance(context, ChatMessageContent):
+        return str(context.to_prompt())
+    return str(context)
+
+
+def _message(item):
+    message = item.to_element()
+    return tostring(message, encoding="unicode", short_empty_elements=False)
+
+
+# Wrap the _get function to safely handle calls without arguments
+def _safe_get_wrapper(context=None, name=None, default=""):
+    if context is None or name is None:
+        return default
+    return _get(context, name, default)
+
+
+def _get(context, name, default=""):
+    """Retrieves a value from the context, with a default if not found."""
+    return context.get(name, default)
+
+
+def _double_open():
+    """Returns the string representing double open braces."""
+    return "{{"
+
+
+def _double_close():
+    """Returns the string representing double close braces."""
+    return "}}"
+
+
+def _array(*args, **kwargs):
+    return list(args)
+
+
+def _camel_case(*args, **kwargs):
+    return "".join([word.capitalize() for word in args[0].split("_")])
+
+
+def _snake_case(*args, **kwargs):
+    arg = args[0]
+    arg = re.sub(r"([A-Z]+)([A-Z][a-z])", r"\1_\2", arg)
+    arg = re.sub(r"([a-z\d])([A-Z])", r"\1_\2", arg)
+    arg = arg.replace("-", "_")
+    return arg.lower()
+
+
+JINJA2_SYSTEM_HELPERS: dict[str, Callable] = {
+    "get": _safe_get_wrapper,
+    "double_open": _double_open,
+    "doubleOpen": _double_open,
+    "double_close": _double_close,
+    "doubleClose": _double_close,
+    "message": _message,
+    "message_to_prompt": _message_to_prompt,
+    "messages": _messages,
+    "messageToPrompt": _message_to_prompt,
+    "array": _array,
+    "camel_case": _camel_case,
+    "camelCase": _camel_case,
+    "snake_case": _snake_case,
+    "snakeCase": _snake_case,
+}