fix bug in matlab import and printing of matlab import (closes #171)

NEWS.md

@@ -1,5 +1,6 @@
 # rio 0.5.11
 
+ * Fixed a bug in `import()` wherein matlab files were ignored unless `format` was specified, as well as a related bug that made importing appear to fail for matlab files. (#171)
  * Fixed a bug in `export()` wherein `format` was ignored. (#99, h/t Sebastian Sauer)
  * Fixed a bug in the importing of European-style semicolon-separated CSV files. Added a test to ensure correct behavior. (#159, h/t Kenneth Rose)
  * Updated documentation to reflect recent changes to the xlsx `export()` method. (#156)

R/import.R

@@ -112,18 +112,20 @@ import <- function(file, format, setclass, which, ...) {
         if (fmt %in% c("gz", "gzip")) {
             fmt <- file_ext(file_path_sans_ext(file, compression = FALSE))
             file <- gzfile(file)
+        } else {
+            fmt <- get_type(fmt)
         }
     } else {
         fmt <- get_type(format)
     }
-
+    
     class(file) <- c(paste0("rio_", fmt), class(file))
     if (missing(which)) {
         x <- .import(file = file, ...)
     } else {
         x <- .import(file = file, which = which, ...)
     }
-
+    
     a <- list(...)
     if (missing(setclass) || is.null(setclass)) {
         if ("data.table" %in% names(a) && isTRUE(a[["data.table"]])) {

R/set_class.R

@@ -12,5 +12,10 @@ set_class <- function(x, class = NULL) {
         }
         return(tibble::as_tibble(x))
     }
-    return(structure(x, class = "data.frame"))
+    out <- structure(x, class = "data.frame")
+    # add row names in case `x` wasn't already a data frame (e.g., matlab list)
+    if (!length(rownames(out))) {
+        rownames(out) <- as.character(seq_len(length(out[,1L,drop = TRUE])))
+    }
+    return(out)
 }

R/utils.R

@@ -92,8 +92,6 @@ get_type <- function(fmt) {
         gnumeric = "gnumeric",
         jpeg = "jpg",
         jpg = "jpg",
-        mat = "matlab",
-        matlab = "matlab",
         npy = "npy",
         png = "png",
         sdmx = "sdmx",

tests/testthat/test_format_matlab.R

@@ -8,6 +8,7 @@ if (requireNamespace("rmatio")) {
 
     test_that("Import from matlab", {
         expect_true(is.data.frame(import("iris.matlab")))
+        expect_true(identical(dim(import("iris.matlab")), dim(iris)))
     })
     unlink("iris.matlab")
 }