Add placeholder option for freetext

[Mikael-Lenander]

Description

What?

Add placeholder option for freetext directive. Placeholder is a text that is shown in an empty input field.

Why?

Specify units etc.

How?

Adds a new option_spec to FreeText class.

Testing

Remember to add or update unit tests for new features and changes.

• How to test your changes in A-plus
• How to test accessibility

What type of test did you run?

• [ ] Accessibility test using the WAVE extension.
• [ ] Django unit tests.
• [ ] Selenium tests.
• [ ] Other test. (Add a description below)
• [x] Manual testing.

Compiled rst code. The placeholder attributes appeared in html files in _build folder.

Did you test the changes in

• [ ] Chrome
• [ ] Firefox
• [ ] This pull request cannot be tested in the browser.

Think of what is affected by these changes and could become broken

Translation

• [ ] Did you modify or add new strings in the user interface? (Read about how to create translation)

Programming style

• [x] Did you follow our style guides?
• [ ] Did you use Python type hinting in all functions that you added or edited? (type hints for function parameters and return values)

Have you updated the README or other relevant documentation?

• [ ] documents inside the doc directory.
• [x] README.md.
• [ ] Aplus Manual.
• [ ] Other documentation (mention below which documentation).

Is it Done?

• [ ] Reviewer has finished the code review
• [ ] After the review, the developer has made changes accordingly
• [ ] Customer/Teacher has accepted the implementation of the feature

Clean up your git commit history before submitting the pull request!

[ihalaij1]

Related issue: apluslms/a-plus#1143

[Mikael-Lenander]

I looked into this in more detail and turns out that there is no need for an additional option in the FreeText class. The placeholder can be added to the :extra: option and it renders nicely. However, the placeholder is not added to form_i18n dictionary for some reason, so translations don't work.

[ihalaij1]

Hey,

I got the placeholder FreeText option working for multilingual courses, it required some changes in MOOC-Grader too. I will be finishing a pull request on it and you can then test it.

[ihalaij1]

I believe I still need to do similar changes to MOOC-Jutut as I did to MOOC-Grader to get the placeholder to display in Jutut exercises too. I'll see if I can figure it out.

[ihalaij1]

@Mikael-Lenander I got the placeholder :extra: option working more easily, since it was already somewhat supported by MOOC-Jutut. I had to make some changes in MOOC-Grader to get the translations working in both MOOC-Jutut questionnaires and normal MOOC-Grader questionnaires.

Could you test the PR and tell me if it fulfills your needs? https://github.com/apluslms/mooc-grader/pull/157

I will close this PR now, since we don't need a new :placeholder: option after all.