DS-3781: Fix bug when stacked variable labels were identical (#33)

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: flipData
 Type: Package
 Title: Functions for extracting and describing data
-Version: 1.6.3
+Version: 1.6.4
 Author: Displayr <opensource@displayr.com>
 Maintainer: Displayr <opensource@displayr.com>
 Description: Functions for extracting data from formulas and

R/stacking.R

@@ -1229,6 +1229,9 @@ stackedValueAttributes <- function(group.ind, input.value.attributes)
 # halfway into a word or number.
 getCommonPrefix <- function(nms, whole.words = FALSE)
 {
+    if (allIdentical(nms))
+        return(nms[1])
+
     common_prefix <- ""
     for (i in 1:min(nchar(nms)))
     {
@@ -1283,6 +1286,9 @@ getCommonSuffixTwoNames <- function(nms)
 # halfway into a word or number.
 getCommonSuffix <- function(nms, whole.words = FALSE)
 {
+    if (allIdentical(nms))
+        return(nms[1])
+
     common_suffix <- ""
     for (i in 1:min(nchar(nms)))
     {

tests/testthat/test-stacking.R

@@ -702,3 +702,15 @@ test_that("DS-3758: special characters at end of variable names", {
                            specify.by = "Variable",
                            manual.stacking = c("Q1_F_c@,Q1_E_c1@,Q1_D_c@,Q1_C_c1@,Q1_A_c@,Q1_B_c1@")), NA)
 })
+
+# cola20.sav has variables with the same labels, e.g. Q10_A, Q10_A_2.
+test_that("DS-3781: identical variable labels", {
+    result <- StackData(findInstDirFile("cola20.sav"),
+                        stack.with.common.labels = "Disabled",
+                        specify.by = "Variable",
+                        manual.stacking = c("Q10_A,Q10_A_2", "Q10_B,Q10_B_2"))
+    expect_equal(unname(result$stacked.data.set.metadata$variable.labels[1]),
+                 "Sometimes I drink cola that is bought by my friends or family")
+    expect_equal(unname(result$stacked.data.set.metadata$variable.labels[2]),
+                 "Three words only")
+})