gt::tab_spanner_delim (>= 0.10.0) no longer allow "delim" to be more than one character

[mcanouil]

In 0.9.0, it was possible to have something like below to get unique names but still pretty tables using spanner for HTML tables.

  FEATURES          CONTRASTS LIMMA__ESTIMATE LIMMA__P_VALUE COUNTS__MEAN COUNTS__SD
1    Gene1 condition: 1 vs. 0      0.32535759   3.066289e-06     21433.05   8287.407
2    Gene2 condition: 1 vs. 0      0.29437665   2.825313e-06     21664.51   7589.840
3    Gene3 condition: 1 vs. 0     -0.37211278   4.192328e-04     22887.60  10130.252
4    Gene4 condition: 1 vs. 0     -0.47107999   1.999919e-03     19977.46  10677.372
5    Gene5 condition: 1 vs. 0     -0.09331177   3.509038e-02     14634.88   2578.446

Reprex:

gt::gt(
  data = structure(list(
    FEATURES = c(
      "Gene1", "Gene2", "Gene3", "Gene4",
      "Gene5"
    ), CONTRASTS = c(
      "condition: 1 vs. 0", "condition: 1 vs. 0",
      "condition: 1 vs. 0", "condition: 1 vs. 0", "condition: 1 vs. 0"
    ), LIMMA__ESTIMATE = c(
      0.325357591624977, 0.294376649868767,
      -0.372112777793342, -0.47107999497371, -0.0933117711552145
    ),
    LIMMA__P_VALUE = c(
      3.06628859857087e-06, 2.8253129711711e-06,
      0.000419232793116877, 0.00199991913409095, 0.0350903776632474
    ), COUNTS__MEAN = c(
      21433.0459458001, 21664.5137266682, 22887.6046442154,
      19977.4641196898, 14634.8752065793
    ), COUNTS__SD = c(
      8287.40744333268,
      7589.84039964603, 10130.2519032155, 10677.3719374534, 2578.44599379548
    )
  ), row.names = c(NA, 5L), class = c("data.frame"))
) |>
  gt::tab_spanner_delim(
    delim = "__",
    columns = dplyr::matches("DESEQ2__|LIMMA__|GLMM__|COUNTS__|ES__|LM__"),
    split = "last"
  )

[mcanouil]

I do not think it is related to the issue at end here and is likely to deserve its own issue.