Merge pull request #130 from robertzk/fix_dplyr_bind_rows_issue

Fix an issue with dplyr::bind_rows

.travis.yml

@@ -19,8 +19,8 @@ before_script:
   - Rscript -e 'if (length(find.package("devtools", quiet = TRUE)) == 0L) { install.packages("devtools", repos = "http://cran.rstudio.com") }'
   - Rscript -e 'devtools::update_packages("devtools", repos = "http://cran.rstudio.com")'
   - Rscript -e 'if (!require("roxygen")) devtools::install_github("klutometis/roxygen")'
-  - Rscript -e 'if (!require("DBI")) devtools::install_github("rstats-db/DBI")'
-  - Rscript -e 'if (!require("RPostgres")) devtools::install_github("robertzk/RPostgres@0.1.1")'
+  - Rscript -e 'devtools::install_github("rstats-db/DBI@ca4e977e7106d5b467b49d202234b0cb7b50d26d")'
+  - Rscript -e 'devtools::install_github("robertzk/RPostgres@0.1.2")'
   - Rscript -e 'if (!require("testthat")) devtools::install_github("hadley/testthat")'
   - Rscript -e 'if (!require("testthatsomemore")) devtools::install_github("robertzk/testthatsomemore")'
   - Rscript -e 'if (!require("syberiaStructure")) devtools::install_github("robertzk/syberiaStructure")'

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: cachemeifyoucan
 Type: Package
 Title: Cache Me If You Can
-Version: 0.2.4
+Version: 0.2.4.1
 Description: One of the most frustrating parts about being a data scientist
     is waiting for data or other large downloads. This package offers a caching
     layer for arbitrary functions that relies on a PostgreSQL backend.

NEWS.md

@@ -1,3 +1,9 @@
+# Version 0.2.4.1
+* Re-replaces dplyr::bind_rows with plyr::rbind.fill because
+  plyr::rbind.fill allows the combination of dataframes with
+  alike content but different classes (e.g., "FALSE" and FALSE),
+  which happens due to type coercion the cached data.
+
 # Version 0.2.4
 * Implements a blacklist of values that are to be returned but not cached.
 * Clean up how `safe_columns` is passed along in the function environment.

R/cache.R

@@ -417,8 +417,17 @@ execute <- function(fcn_call, keys) {
   ## Actually compute for the uncached keys
   cached_data <- compute_cached_data(fcn_call, cached_keys)
 
-  data <- dplyr::bind_rows(uncached_data, cached_data)
-  class(data) <- "data.frame"  # un-dplyr
+  result <- try({
+    # Incompatible types could cause an error with bind_rows,
+    # which rbind.fill will handle gracefully below.
+    data <- dplyr::bind_rows(uncached_data, cached_data)
+    class(data) <- "data.frame" # un-dplyr
+  }, silent = TRUE)
+
+  if (is(try, "try-error")) {
+    data <- plyr::rbind.fill(uncached_data, cached_data)
+  }
+
   if (fcn_call$force) {
     ## restore column names using existing cache columns
     old_columns <- get_column_names_from_table(fcn_call)