diff --git a/R/parse-query.R b/R/parse-query.R
index ade461bd4..832e93f89 100644
--- a/R/parse-query.R
+++ b/R/parse-query.R
@@ -184,26 +184,7 @@ combine_keys <- function(obj, type) {
       function(x) {
         unname(unlist(x))
       },
-    "multi" =
-      function(x) {
-        if (length(x) == 1) {
-          # return first item only
-          return(x[[1]])
-        }
-
-        # return list of internal named items
-        # aka... unlist the top layer only. Maintain the inner layer names
-        x_new <- lapply(unname(x), function(x_item) {
-          if (is.atomic(x_item)) {
-            # handles things like `parse_text` which returns atomic values
-            return(list(x_item))
-          }
-
-          # handles things like `parse_octet` which returns a (possibly) named list
-          x_item
-        })
-        as.list(unlist(x_new, recursive = FALSE))
-      }
+    stop("unknown type: ", type)
   )
 
   # equivalent code output, `split` is much faster with larger objects
diff --git a/tests/testthat/test-combine-keys.R b/tests/testthat/test-combine-keys.R
deleted file mode 100644
index 123d3dce3..000000000
--- a/tests/testthat/test-combine-keys.R
+++ /dev/null
@@ -1,109 +0,0 @@
-context("combine keys")
-
-test_that("query keys with same name are combined", {
-  a <- list(A = 1, A = 2, B = 3, A = 4, B = 5)
-  expect_equal(combine_keys(a, "query"), list(A = c(1,2,4), B = c(3,5)))
-})
-
-test_that("multi part keys with same name are combined", {
-  # no lists
-  a <- list(A = 1, A = 2, B = 3, A = 4, B = 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,2,4), B = list(3,5)))
-
-  # unnamed lists
-  a <- list(A = 1, A = list(11,12), B = 3, A = 4, B = 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,11,12,4), B = list(3,5)))
-
-  # partial named lists
-  a <- list(A = 1, A = list(X = 11,12), B = 3, A = list(Y = 4), B = 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,X = 11, 12, Y = 4), B = list(3,5)))
-
-  # named lists
-  a <- list(A = 1, A = list(X = 11, Y = 12), B = 3, A = list(Z = 4), B = 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,X = 11, Y = 12, Z = 4), B = list(3,5)))
-})
-
-
-test_that("multi part keys with no name are left alone", {
-  a <- list(A = 1, 2, A = 3, B = 4, 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,3), B = 4, 2, 5))
-
-  a <- list(A = 1, 2, A = 3, B = 4, 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,3), B = 4, 2, 5))
-  a <- list(A = 1, 2, A = 3, B = 4, 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,3), B = 4, 2, 5))
-})
-
-
-test_that("multi part keys with no names are untouched", {
-  a <- list(1,2,3,4,5)
-  expect_equal(combine_keys(a, "multi"), a)
-
-  a <- list(1,list(2),3,4,5)
-  expect_equal(combine_keys(a, "multi"), a)
-
-  a <- list(1,list(2),3,list(4,5))
-  expect_equal(combine_keys(a, "multi"), a)
-
-  a <- list(list(1),list(2),list(3),list(4, 5))
-  expect_equal(combine_keys(a, "multi"), a)
-})
-
-test_that("multi part keys with all same name", {
-  a <- list(A = 1, A = 2, A = 3, A = 4, A = 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,2,3,4,5)))
-
-  a <- list(A = 1,A = list(2),A = 3,A = 4,A = 5)
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,2,3,4,5)))
-
-  a <- list(A = 1,A = list(2),A = 3,A = list(4,5))
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,2,3,4,5)))
-
-  a <- list(A = 1,A = list(2),A = 3,A = list(4,Y = 5))
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,2,3,4,Y = 5)))
-
-  a <- list(A = 1,A = list(2),A = 3,A = list(X = 4,Y = 5))
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,2,3,X = 4,Y = 5)))
-
-  a <- list(A = 1,A = list(B = 2),A = 3,A = list(X = 4,Y = 5))
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,B = 2,3,X = 4,Y = 5)))
-})
-
-
-test_that("raw values are not combined", {
-  x <- charToRaw("testval")
-  y <- charToRaw("other testval")
-
-  a <- list(x,y)
-  expect_equal(combine_keys(a, "multi"), list(x, y))
-
-  a <- list(A = x,y)
-  expect_equal(combine_keys(a, "multi"), list(A = x, y))
-
-  a <- list(A = x, B = y)
-  expect_equal(combine_keys(a, "multi"), list(A = x, B = y))
-
-  a <- list(A = x, A = y)
-  expect_equal(combine_keys(a, "multi"), list(A = list(x, y)))
-
-  a <- list(A = list(X = x), A = y)
-  a <- list(A = list(X = x), A = list(y))
-  expect_equal(combine_keys(a, "multi"), list(A = list(X = x, y)))
-
-  a <- list(A = list(x), A = list(Y = y))
-  expect_equal(combine_keys(a, "multi"), list(A = list(x, Y = y)))
-
-  a <- list(A = list(X = x), A = list(Y = y))
-  expect_equal(combine_keys(a, "multi"), list(A = list(X = x, Y = y)))
-
-
-  a <- list(A = list(X = x), A = list(Y = y), A = "foobar")
-  expect_equal(combine_keys(a, "multi"), list(A = list(X = x, Y = y, "foobar")))
-})
-
-
-test_that("inner list structures are preserved", {
-
-  a <- list(A = 1, B = 2, A = list(X = 3, Y = 4))
-  expect_equal(combine_keys(a, "multi"), list(A = list(1,X = 3, Y = 4), B = 2))
-})
diff --git a/tests/testthat/test-querystring.R b/tests/testthat/test-querystring.R
index 8c8268f5b..34bef06fd 100644
--- a/tests/testthat/test-querystring.R
+++ b/tests/testthat/test-querystring.R
@@ -70,3 +70,8 @@ test_that("different lengths of query string return same shape", {
 
   }
 })
+
+test_that("query keys with same name are combined", {
+  a <- list(A = 1, A = 2, B = 3, A = 4, B = 5)
+  expect_equal(combine_keys(a, "query"), list(A = c(1,2,4), B = c(3,5)))
+})