knit to pdf fails when tab_header is specified without a subtitle

[tbradley1013]

When trying to include a gt inside of an Rmarkdown document being knit to pdf, the knitting fails if tab_header is specified without a subtitle.

.Rmd file

---
title: "tab header test"
date: "2/25/2019"
output: pdf_document
---

```{r}
library(tidyverse)
library(gt)
```

```{r}
gtcars %>%
  dplyr::select(mfr, model, msrp) %>%
  dplyr::slice(1:5) %>%
  gt() %>%
  tab_header(
    title = md("Data listing from **gtcars**")
    # subtitle = md("`gtcars` is an R dataset")
  )

```

Error

! LaTeX Error: There's no line here to end.

Error: Failed to compile test-tab-header.tex. See test-tab-header.log for more info.
Execution halted

If you include the subtitle, the pdf knits correctly.

[ulf85]

Thanks for posting this issue and that skipping subtitle is the problem. I had the same issue.
A workaround for me was to set subtitle to an empty space:
tab_header(title = md("Data listing from **gtcars**"), subtitle = md(" "))

Then there is a little space between the title and the table. For me that was OK.

[microbe]

I found this code the LaTeX generated by gt & knitr.
The \small \\ is there even when no subtitle is defined in tab_header.
If I remove it in the LaTeX, then it compiles well.

\begin{longtable}{rrrrrrrrrrr}
\caption*{
\large MT Cars\\ 
\small \\ 
} \\ 

[rich-iannone]

A recent fix in the development version of the package fixes this. So, closing now.