fix(webshot): Rethrow underlying chromote errors (#69)

* fix(webshot): Rethrow underlying chromote errors

* docs: Add news item

Author: gadenbuie

NEWS.md

@@ -1,5 +1,7 @@
 # webshot2 (development version)
 
+* `webshot()` now surfaces errors that occur when working with the lower-level screenshot API provided by Chrome via `{chromote}`. (#69)
+
 # webshot2 0.1.1
 
 * `webshot()` now supports JPEG (`.jpg` or `.jpeg`) and WEBP (`.webp`) image formats. (@trafficonese #45)

R/webshot.R

@@ -251,6 +251,7 @@ new_session_screenshot <- function(
 
 
   s <- NULL
+  err <- NULL
 
   p <- chromote$new_session(wait_ = FALSE,
       width = vwidth,
@@ -296,8 +297,14 @@ new_session_screenshot <- function(
       if (!isTRUE(quiet)) message(url, " screenshot completed")
       normalizePath(value)
     })$
+    catch(function(err) {
+      err <<- err
+    })$
     finally(function() {
-      s$close()
+      # Close down the session if we successfully started one
+      if (!is.null(s)) s$close()
+      # Or rethrow the error if we caught one
+      if (!is.null(err)) signalCondition(err)
     })
 
   p