[Bug]: Regression: Default values overwrite empty fields in TextFileOutput transform

[fskorgen]

Apache Hop version?

2.18-SNAPSHOT

Java version?

21

Operating system

Windows

What happened?

There appears to be a change in behavior in the TextFileOutput transform regarding default values.

When loading an existing pipeline where a field (e.g., enclosure) is explicitly set to an empty string (""), the value is not preserved. Instead, upon reopening the pipeline, the field is automatically populated with the default value.

This behavior differs from previous versions (e.g., 2.17), where empty string values were retained correctly when reloading a pipeline.

Steps to Reproduce:

Create or open a pipeline with a TextFileOutput transform.
Set a field such as enclosure to an empty string.
Save the pipeline.
Close and reopen the pipeline.

Expected Behavior:
The field should remain as an empty string ("") after reopening.

Actual Behavior:
The field is replaced with the default value.

Version:
Observed in current version (please specify if needed).
Not present in version 2.17.

Additional Context:
This may impact pipelines that rely on explicitly empty values rather than defaults.
We have a lot of pipelines using the TextFileOutput to write a single field as Json/Xml files

Issue Priority

Priority: 3

Issue Component

Component: Transforms

[fskorgen]

If we move the separator and enclosure configuration back into the setDefault function, the problem should be resolved, as this ensures the expected default values are consistently applied during initialization

E.g.:

  public TextFileOutputMeta() {
    super();
    fileSettings = new FileSettings();
    outputFields = new ArrayList<>();
    createParentFolder = true;
    separator = ""; // moved to setDefault - ";"
    enclosure = ""; // moved to setDefault - "\""
    enclosureForced = false;
    enclosureFixDisabled = false;
    headerEnabled = true;
    footerEnabled = false;
    fileFormat = "DOS";
    setFileCompression(fileCompressionTypeCodes[FILE_COMPRESSION_TYPE_NONE]);
  }

  @Override
  public void setDefault() {
    separator = ";";
    enclosure = "\"";
  }

[hansva]

.take-issue

Currently, empty tags are being treated as null values. I'm changing the deserialization logic to return an empty string when the tag is present but empty.