When R Markdown documents use fonts with spaces in their names (e.g., "Noto Emoji", "DejaVu Sans"), automatic package installation via tinytex::parse_install() fails.

Root Cause

The font_ext() function in R/latex.R:663-667 generates search patterns that preserve spaces:

font_ext = function(x) {
  i = !grepl('[.]', x)
  x[i] = paste0(x[i], '(-(Bold|Italic|Regular).*)?[.](tfm|afm|mf|otf|ttf)')
  x
}

When LaTeX reports Font "Noto Emoji" not found, this generates:

Noto Emoji(-(Bold|Italic|Regular).*)?[.](tfm|afm|mf|otf|ttf)

But font files never have spaces in their names:

• NotoEmoji-Regular.ttf ✓
• DejaVuSans-Bold.ttf ✓

So tlmgr search --file fails to find the package.

Solution

Replace spaces with \s* pattern to match files with or without spaces:

font_ext = function(x) {
  i = !grepl('[.]', x)
  # Replace spaces with \s* for regex matching
  x[i] = gsub('\s+', '\\s*', x[i])
  x[i] = paste0(x[i], '(-(Bold|Italic|Regular).*)?[.](tfm|afm|mf|otf|ttf)')
  x
}

This generates: Noto\s*Emoji(-(Bold|Italic|Regular).*)?[.](tfm|afm|mf|otf|ttf)

Verification

# Test that pattern works with tlmgr
system2('tlmgr', c('search', '--file', '--global', 'Noto\s*Emoji'))
# Returns: noto-emoji package ✓

system2('tlmgr', c('search', '--file', '--global', 'DejaVu\s*Sans'))
# Returns: dejavu package ✓

Related

This issue was discovered and fixed in quarto-dev/quarto-cli#13726, which uses patterns derived from tinytex.