Cambridge Core: Don't prefix abstracts of articles with a graphical abstract

[mjthoraval]

Abstracts of Cambridge Core articles that have a graphical abstract are saved with a stray , in front:

, We study the effect of insoluble surfactants on the impact of...

Such articles have two div.abstract nodes — the first holds only the figure and has no text. ZU.xpathText() joins all matched nodes with its default ", " delimiter, so the empty first node contributed the separator. This affects a lot of Journal of Fluid Mechanics articles; 188 of the 1367 JFM items in my own library are affected.

The fix takes the first div.abstract that actually has text. It deliberately does not pass delimiter: '' to xpathText(), which would silently concatenate genuinely multi-node abstracts instead.

The text now also goes through ZU.trimInternal(). xpathText() does no trimming, so abstracts could pick up a trailing space as well — e.g. the abstract of Micro-bubble morphologies following drop impacts onto a pool surface is saved 869 characters long, one trailing space more than its text. All seven existing test cases with abstracts are already trimInternal-identical, so nothing there changes.

Verification

The new test case (10.1017/jfm.2023.224) fails on master's code and passes with this change — I ran the harness on master's code with the new test case added to confirm the guard actually catches the bug. No other case changes state:

run (local, subscribed network)	failing cases
master, as-is (12 cases)	1, 2, 5, 6, 9, 10, 12
master's code + new test case	1, 2, 5, 6, 9, 10, 12, 13
this branch (13 cases)	1, 2, 5, 6, 9, 10, 12

Case 13 is the only one whose state changes. Cases 1, 2, 9 and 10 fail locally for an
unrelated, environment-dependent reason described below; on CI they pass, so this branch's
CI shows only 5, 6 and 12 — the same three as master.

A note on four other cases

I initially also refreshed the url of cases 1, 2, 9 and 10, having seen them fail locally: Cambridge redirects /article/abs/<slug>/<id> to /article/<slug>/<id>, so the saved url didn't match. That was wrong and I've reverted it — the redirect only happens for readers with access to the article, so an institutional network gets the canonical form while CI gets the /abs/ form the test cases already record. The existing URLs are correct; those four only fail on a subscribed network.

Left alone: the three book/bookSection cases

Cases 5, 6 and 12 fail on master too, for a reason unrelated to this PR, and I'd rather flag it than record it as expected output.

Cambridge's RIS export now emits the DOI with the value itself prefixed:

DO  - DOI: 10.1017/9781108770750

The connector's bundled schema (version 28) doesn't allow DOI on book or bookSection, so the value is dropped instead of falling back to Extra — which is where these test cases expect it ("extra": "DOI: 10.1017/9781108638210"). A current desktop client keeps it as a proper DOI field (I checked: it imports as 10.1017/9781108770750 either way, so cleanDOI copes with the prefix), so saved items are unaffected.

So this looks like a test-environment artifact rather than a user-facing regression, and refreshing those fixtures would bake "no DOI" into the repo. Happy to include a fix if you'd prefer one here — stripping the prefix in this translator would be a one-liner — but it seemed better not to guess at how you'd want the schema pinning handled.

[mjthoraval]

Small correction on my own part, since the first CI run here looked worse than it should have: I'd also refreshed the url in cases 1, 2, 9 and 10, having watched them fail locally. That was wrong and is reverted in 94bd249.

/article/abs/<slug>/<id> only redirects to /article/<slug>/<id> for readers with access to the article, so the saved url differs by network — an institutional connection gets the canonical form, CI gets the /abs/ form the fixtures already record. The existing URLs are correct, and my change had broken four cases that were passing here.

CI on the current head fails only cases 5, 6 and 12 — the book/bookSection DOI issue described in the description, which fail on master too. Case 13, the one this fix adds, passes.