1  # SPDX-FileCopyrightText: 2022-present deepset GmbH <info@deepset.ai>
 2  #
 3  # SPDX-License-Identifier: Apache-2.0
 4  
 5  import pytest
 6  
 7  from haystack.testing.sample_components import FString
 8  
 9  
10  def test_fstring_with_one_var():
11      fstring = FString(template="Hello, {name}!", variables=["name"])
12      output = fstring.run(name="Alice")
13      assert output == {"string": "Hello, Alice!"}
14  
15  
16  def test_fstring_with_no_vars():
17      fstring = FString(template="No variables in this template.", variables=[])
18      output = fstring.run()
19      assert output == {"string": "No variables in this template."}
20  
21  
22  def test_fstring_with_template_at_runtime():
23      fstring = FString(template="Hello {name}", variables=["name"])
24      output = fstring.run(template="Goodbye {name}!", name="Alice")
25      assert output == {"string": "Goodbye Alice!"}
26  
27  
28  def test_fstring_with_vars_mismatch():
29      fstring = FString(template="Hello {name}", variables=["name"])
30      with pytest.raises(KeyError):
31          fstring.run(template="Goodbye {person}!", name="Alice")
32  
33  
34  def test_fstring_with_vars_in_excess():
35      fstring = FString(template="Hello {name}", variables=["name"])
36      output = fstring.run(template="Goodbye!", name="Alice")
37      assert output == {"string": "Goodbye!"}
38  
39  
40  def test_fstring_with_vars_missing():
41      fstring = FString(template="{greeting}, {name}!", variables=["name"])
42      with pytest.raises(KeyError):
43          fstring.run(greeting="Hello")