When an article is selected to translate (either through search, suggestions or an external link) a confirmation step is shown (T276221).
When the target article exists for the selected language, the confirmation step presents the option to expand it by translating a new section. However, the situation may be slightly different depending on the number of sections available.

This ticket proposes to adjust the text and actions to cover the different combinations in a way that makes sense to each context. These depend on the number of sections missing and present for the article in the selected languages. A visual summary is provided below:

Several sections missing

More than one section from the source is missing in the target language. Thus, there are several options of sections to expand the article for the user to chose from.

missing>1:

Expand with “X” and N more sections
[Select section to translate]

• X is the first missing section.
• N is the number of sections
• The action leads to the "Pick a section step"

Only one section missing (other sections present)

One section from the source is missing in the target language, but other sections have been identified as present in the target. Thus, users are expected to translate the missing one but choosing a different one still makes sense.

missing=1 & present>0:

Expand with “X” or check existing sections
[Select section to translate]

• X is the missing section.
• The action leads to the "Pick a section step"

Only one section missing (no more sections)

Only one section in the source article which is missing in the target language. Thus, selecting the section is the only option forward.

missing=1 & present=0:

Expand with “X” section
[View section to translate]

• X is the missing section.
• The action goes directly to the “Compare the contents before translating” step. This will skip the "Pick a section" step since it would be a list with only one option.

All sections present already

There is one or more sections but all of them are already present. Thus, users are less likely to translate existing sections but it is still possible.

missing=0 & present>0:

No sections missing. Check existing ones.
[Select section to translate]

• The action uses a regular (non-primary) button and leads to the "Pick a section step".

No sections at all

The source article has no sections. Thus, users can only translate the lead section to replace the target article. Since this requires to support to translate new articles (T260144) and specific considerations when overwriting existing content, initially we can disable this option.

missing = 0 & present = 0:

No sections available to translate. Try for a different topic or language.
[Select section to translate]

• The action is disabled