fix: WriteLineToFile truncates file when opening

[mcwarman]

This ensures that when a line is replaced if the value is shorter than the existing line the remaining values are not left in the buffer.

Fix #1915

Test

To test this pull request, you can run the following commands:

cd pkg/plugins/resources/file
go test

test.yaml

targets:
  updateSyncServiceVersion:
    name: Bump Sync Service version
    kind: file
    disablesourceinput: true
    spec:
      file: file.txt
      line: 1
      content: org.alfresco.services.sync:service-sync:${ARTIFACT_VERSION:-5.0.0-A13}:jar
  updateDeviceSyncRepoVersion:
    name: Bump Device Sync Repo version
    kind: file
    disablesourceinput: true
    spec:
      file: file.txt
      line: 2
      content: org.alfresco.services.sync:alfresco-device-sync-repo:${ARTIFACT_VERSION:-5.0.0-A13}:amp

file.txt

org.alfresco.services.sync:service-sync:${ARTIFACT_VERSION:-5.0.1-SNAPSHOT}:jar
org.alfresco.services.sync:alfresco-device-sync-repo:${ARTIFACT_VERSION:-5.0.0-SNAPSHOT}:amp

[olblak]

Thanks for fixing this issue

[olblak]

Thanks for the example, I just tested manually and your fix works as expected