recode_char incorrectly replaces values when regex and default are both set

[alinacherkas]

Describe the bug

When using recode_char with regex set to TRUE and default value specified, the function incorrectly handles replacements. It seems that the issue is related to indices and how default value is handled internally. The issue was originally found in 2.0.15 but is still there in 2.0.17.

Steps/Code to Reproduce

x <- c("-1", "1", "0", "2", "-2")
collapse::recode_char(x, "-\\d+" = "negative", "0" = "zero", default = "positive", regex = T)
# [1] "positive" "positive" "zero" "positive" "positive"

Expected Results

x <- c("-1", "1", "0", "2", "-2")
collapse::recode_char(x, "-\\d+" = "negative", "0" = "zero", regex = T)
# [1] "negative" "1" "zero" "2" "negative"
collapse::recode_char(x, "0" = "zero", "-\\d+" = "negative", default = "positive", regex = T)
# [1] "negative" "positive" "zero" "positive" "negative"
collapse::recode_char(x, "-\\d+" = "negative", "0" = "zero", default = "positive", regex = T)
# [1] "negative" "positive" "zero" "positive" "negative"

Actual Results

x <- c("-1", "1", "0", "2", "-2")
collapse::recode_char(x, "-\\d+" = "negative", "0" = "zero", regex = T)
# [1] "negative" "1" "zero" "2" "negative"
collapse::recode_char(x, "0" = "zero", "-\\d+" = "negative", default = "positive", regex = T)
# [1] "negative" "positive" "zero" "positive" "negative"
collapse::recode_char(x, "-\\d+" = "negative", "0" = "zero", default = "positive", regex = T)
# [1] "positive" "positive" "zero" "positive" "positive"

Session Info

> sessionInfo()
R version 4.3.2 (2023-10-31)
Platform: aarch64-apple-darwin20 (64-bit)
Running under: macOS 15.0.1

Matrix products: default
BLAS:   /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib 
LAPACK: /Library/Frameworks/R.framework/Versions/4.3-arm64/Resources/lib/libRlapack.dylib;  LAPACK version 3.11.0

locale:
[1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8

time zone: ...
tzcode source: internal

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] collapse_2.0.17  testthat_3.2.1.1

loaded via a namespace (and not attached):
 [1] miniUI_0.1.1.1    compiler_4.3.2    brio_1.1.5        promises_1.3.0    Rcpp_1.0.12       stringr_1.5.1     parallel_4.3.2    later_1.3.2      
 [9] fastmap_1.1.1     mime_0.12         R6_2.5.1          htmlwidgets_1.6.4 tibble_3.2.1      desc_1.4.3        profvis_0.3.8     rprojroot_2.0.4  
[17] shiny_1.8.1.1     pillar_1.9.0      rlang_1.1.3       utf8_1.2.4        cachem_1.0.8      stringi_1.8.3     httpuv_1.6.15     fs_1.6.4         
[25] pkgload_1.3.4     memoise_2.0.1     cli_3.6.2         withr_3.0.0       magrittr_2.0.3    digest_0.6.35     rstudioapi_0.16.0 xtable_1.8-4     
[33] remotes_2.5.0     devtools_2.4.5    lifecycle_1.0.4   waldo_0.5.2       vctrs_0.6.5       glue_1.7.0        urlchecker_1.0.1  sessioninfo_1.2.2
[41] pkgbuild_1.4.4    fansi_1.0.6       purrr_1.0.2       pkgconfig_2.0.3   tools_4.3.2       usethis_2.2.3     ellipsis_0.3.2    htmltools_0.5.8.1