Coverage for haystack/components/joiners/string_joiner.py: 100%

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1# SPDX-FileCopyrightText: 2022-present deepset GmbH <info@deepset.ai> 

2# 

3# SPDX-License-Identifier: Apache-2.0 

4 

5 

6from haystack import component 

7from haystack.core.component.types import Variadic 

8 

9 

10@component 

11class StringJoiner: 

12 """ 

13 Component to join strings from different components to a list of strings. 

14 

15 ### Usage example 

16 

17 ```python 

18 from haystack.components.joiners import StringJoiner 

19 from haystack.components.builders import PromptBuilder 

20 from haystack.core.pipeline import Pipeline 

21 

22 string_1 = "What's Natural Language Processing?" 

23 string_2 = "What is life?" 

24 

25 pipeline = Pipeline() 

26 pipeline.add_component("prompt_builder_1", PromptBuilder("Builder 1: {{query}}")) 

27 pipeline.add_component("prompt_builder_2", PromptBuilder("Builder 2: {{query}}")) 

28 pipeline.add_component("string_joiner", StringJoiner()) 

29 

30 pipeline.connect("prompt_builder_1.prompt", "string_joiner.strings") 

31 pipeline.connect("prompt_builder_2.prompt", "string_joiner.strings") 

32 

33 print(pipeline.run(data={"prompt_builder_1": {"query": string_1}, "prompt_builder_2": {"query": string_2}})) 

34 

35 # >> {"string_joiner": {"strings": ["Builder 1: What's Natural Language Processing?", "Builder 2: What is life?"]}} 

36 ``` 

37 """ 

38 

39 @component.output_types(strings=list[str]) 

40 def run(self, strings: Variadic[str]) -> dict[str, list[str]]: 

41 """ 

42 Joins strings into a list of strings 

43 

44 :param strings: 

45 strings from different components 

46 

47 :returns: 

48 A dictionary with the following keys: 

49 - `strings`: Merged list of strings 

50 """ 

51 

52 out_strings = list(strings) 

53 return {"strings": out_strings}