updated the documentation

Author: JW-96

docs/input_spec.rst

@@ -162,11 +162,17 @@ In the example we used multiple keys in the metadata dictionary including `help_
    A flag that specifies if the file extension should be removed from the field value.
    Used in order to create an output specification.
 
-
 `readonly` (`bool`, default: `False`):
    If `True` the input field can't be provided by the user but it aggregates other input fields
    (for example the fields with `argstr: -o {fldA} {fldB}`).
 
+`formatter` (`function`):
+   If provided the `argstr` of the field is created using the function. This function can for example
+   be used to combine several inputs into one command argument.
+   The function can take `field` (this input field will be passed to the function),
+   `inputs` (entire `inputs` will be passed) or any input field name
+   (a specific input field will be sent).
+
 
 Validators
 ----------

docs/output_spec.rst

@@ -61,6 +61,9 @@ The metadata dictionary for `output_spec` can include:
 `help_string` (`str`, mandatory):
    A short description of the input field. The same as in `input_spec`.
 
+`mandatory` (`bool`, default: `False`):
+   If `True` the output file has to exist, otherwise an error will be raised.
+
 `output_file_template` (`str`):
    If provided the output file name (or list of file names) is created using the template.
    The template can use other fields, e.g. `{file1}`. The same as in `input_spec`.
@@ -69,11 +72,14 @@ The metadata dictionary for `output_spec` can include:
    If provided the field is added to the output spec with changed name.
    The same as in `input_spec`.
 
+`absolute_path` (`bool` default: `False`):
+   A flag that specifies if the `output_file_template` is an absolute path. If the flag is not set,
+   then the `output_file_template` is searched in the nodes output directory.
+
 `keep_extension` (`bool`, default: `True`):
    A flag that specifies if the file extension should be removed from the field value.
    The same as in `input_spec`.
 
-
 `requires` (`list`):
    List of field names that are required to create a specific output.
    The fields do not have to be a part of the `output_file_template` and

pydra/engine/tests/test_shelltask_inputspec.py

@@ -2425,7 +2425,7 @@ def formatter_4(field):
 
 
 def test_shellspec_formatter_splitter_2(tmpdir):
-    """test the input callable 'formatter'."""
+    """test the input callable 'formatter' when a splitter is used on an argument of the formatter."""
 
     def spec_info(formatter):
         return SpecInfo(