Merge pull request #492 from rstudio/bugfix/0.10misc

Miscellaneous bug fixes

R/imageutils.R

@@ -42,6 +42,9 @@ plotPNG <- function(func, filename=tempfile(fileext='.png'),
   }
 
   pngfun(filename=filename, width=width, height=height, res=res, ...)
+  # Call plot.new() so that even if no plotting operations are performed
+  # at least we have a blank background
+  plot.new()
   dv <- dev.cur()
   tryCatch(shinyCallingHandlers(func()), finally = dev.off(dv))
 

R/shinywrappers.R

@@ -120,8 +120,11 @@ renderPlot <- function(expr, width='auto', height='auto', res=72, ...,
     plotFunc <- function() {
       # Actually perform the plotting
       result <- withVisible(func())
-      if (result$visible)
-        print(result$value)
+      if (result$visible) {
+        # Use capture.output to squelch printing to the actual console; we
+        # are only interested in plot output
+        capture.output(print(result$value))
+      }
 
       # Now capture some graphics device info before we close it
       usrCoords <- par('usr')

inst/www/shared/shiny.js

@@ -1072,10 +1072,11 @@
       this.renderError(el, err);
     };
     this.renderError = function(el, err) {
+      this.clearError(el);
       if (err.message === '') {
         // not really error, but we just need to wait (e.g. action buttons)
         $(el).empty();
-        return this.clearError(el);
+        return;
       }
       var errClass = 'shiny-output-error';
       if (err.type !== null) {