Only try building R files if there are some

diff --git a/Makefile b/Makefile
index 994d66b9cd57e90bcea464a24ad5658e881852d6..c8011ddeedbbc546607b7b8413bcfcd2ffdcf78d 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -78,7 +78,7 @@ HTML_DST = \
 
 ## lesson-rmd:    : convert Rmarkdown files to markdown
 lesson-rmd: $(RMD_SRC)
-       @bin/knit_lessons.sh
+       @bin/knit_lessons.sh $(RMD_SRC)
 
 ## lesson-check   : validate lesson Markdown.
 lesson-check :

diff --git a/bin/knit_lessons.sh b/bin/knit_lessons.sh
index ff5443b0b003c00668b791c0ef5a9cb0e8bd90e1..3a2395f3cf803ffaa90369936fd253ab06994e71 100755 (executable)
--- a/bin/knit_lessons.sh
+++ b/bin/knit_lessons.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
-if [ -d "_episodes_rmd" ] ; then
+# Only try running R to translate files if there are some files present.
+# The Makefile passes in the names of files.
+
+if [ $# -ne 0 ] ; then
     Rscript -e "source('bin/generate_md_episodes.R')"
 fi