Adds 100 character warning to AGU article (#212)

* Adds check for 100 chars limit

* Changes eval

* Removes test keypoints

Author: eliocamp

inst/rmarkdown/templates/agu_article/skeleton/skeleton.Rmd

@@ -66,7 +66,16 @@ knitr::opts_chunk$set(
   out.extra = "",   # To force the use of figure enviroment
   fig.cap = "Please caption every figure"
 )
+```
 
+```{r keypoints_check, echo=FALSE, results='asis', eval = TRUE}
+# This chunk adds a warning if any keypoint is longer than 100 characters. 
+# To disable it, you can remove it or set eval to FALSE.
+if (any(nchar(rmarkdown::metadata$keypoints) > 100)) {
+  cat("\\textcolor{red}{\\textbf{Warning}: keypoint(s)", 
+      knitr::combine_words(which(nchar(rmarkdown::metadata$keypoints) > 100)), 
+      "longer than 100 characters.}")
+}
 ```
 
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