condformat

• Bump the minimum required version of all versioned dependencies to the release that was current about a year ago, rather than today's exact latest release, so users aren't forced onto a brand new patch just to install condformat (part of #43): dplyr (>= 1.1.4), gtable (>= 0.3.6), htmlTable (>= 2.4.3), htmltools (>= 0.5.8.1), knitr (>= 1.50), openxlsx (>= 4.2.8), rmarkdown (>= 2.29), rlang (>= 1.1.6), scales (>= 1.4.0), tibble (>= 3.3.0), tidyselect (>= 1.2.1), shiny (>= 1.11.1), testthat (>= 3.2.3) and vdiffr (>= 1.0.8). gridExtra's floor (>= 2.3) is unchanged, as that release is still the latest on CRAN as of a year ago.

New features

• rule_fill_bar() is now supported in Excel output, rendered using Excel's own native data bar conditional formatting (coloured with low) instead of being dropped with an "unsupported rule" warning. This only applies when expression is left at its default (or explicitly .col), since Excel data bars always reflect a cell's own displayed value against a range and can't replicate an arbitrary custom expression; in that case the data bar itself is skipped (with a warning) but the flat background/na.value cell colours are still applied, as before.
• Export condformat2excelsheet(), which writes a condformat table into a worksheet of an openxlsx workbook you're already building, without creating or saving the workbook itself (closes #25). Its docs show how to combine condformat's own cell styling with your own openxlsx::addStyle() calls (e.g. a number format) via stack = TRUE, since addStyle() replaces existing styles by default.
• Add a .col pronoun usable in the expression argument of rule_fill_discrete(), rule_fill_gradient(), rule_fill_gradient2(), rule_fill_bar(), rule_text_bold(), rule_text_color() and rule_css(). When columns selects more than one column, .col is bound to each column's own values in turn, so a single rule call can format several columns based on each one's own condition (closes #19): rule_fill_discrete(c(Sepal.Length, Sepal.Width), .col > 3) is now equivalent to chaining the rule once per column. expression now also defaults to .col when omitted, replacing the previous behaviour of silently using only the first selected column (with a warning) when no expression was given for a multi-column selection.

Fixes

• Fix condformat2excel()/condformat2excelsheet() silently discarding any pre-existing cell formatting on every export — including a Date column's automatic format from openxlsx::writeData() — even for cells with no condformat rule applied to them. condformat2excelsheet()'s own styling now uses stack = TRUE internally, so it merges with, rather than replaces, formatting that was already there (related to #25).
• Fix lockcells = TRUE being ignored (or worse, unlocking cells) for LaTeX and grob/gtable output in rule_fill_discrete(), rule_fill_gradient(), rule_fill_gradient2(), rule_text_bold() and rule_text_color(). HTML and Excel output were not affected.
• Fix theme_htmlTable() discarding arguments accumulated from earlier theme_htmlTable() calls in the same pipeline, due to a %in% check against list values instead of list names.
• Fix rule_fill_bar()'s na.value never being applied to background-color in HTML output: the CSS mask used to gate that assignment already excluded NA cells, so the assignment was dead code.
• Fix rule_fill_bar() erroring in grob/gtable output when a value rescaled to exactly 0% of the bar width (colorRampPalette() can't return zero colours); such cells now render with just the background colour.
• Fix rule_fill_bar()'s lockcells = TRUE not protecting NA cells from later CSS/HTML rules, and not protecting any cell (NA or not) from later grob/gtable rules: the grob/gtable renderer painted every targeted cell unconditionally and never checked incoming lock state at all.
• Fix rule_text_bold(), rule_text_color() and rule_css() erroring when expression evaluates to a single (scalar) value on a table with more than one row, unlike rule_fill_discrete(), rule_fill_gradient(), rule_fill_gradient2() and rule_fill_bar(), which already recycled such values to every row.

Other

• Fix the bundled shiny example (inst/shinyexample/): requireNamespace() now passes quietly = TRUE, so it no longer prints a package-startup message every time the optional colourpicker dependency isn't installed. Also modernised the legacy shinyUI()/shinyServer() wrappers to the current ui <- ... / server <- function(input, output) {...} style.