Test that 'git2r_arg_check_branch' raise error

Signed-off-by: Stefan Widgren <stefan.widgren@gmail.com>

tests/branch.R

@@ -67,6 +67,31 @@ b <- branch_create(commit.2, name = "test", force = TRUE)
 stopifnot(identical(branch_target(branches(repo)[[1]]),
                     branch_target(branches(repo)[[2]])))
 
+## Test arguments
+res <- tools::assertError(.Call(git2r:::git2r_branch_delete, NULL))
+stopifnot(length(grep("'branch' must be a S4 class git_branch",
+                      res[[1]]$message)) > 0)
+res <- tools::assertError(.Call(git2r:::git2r_branch_delete, 3))
+stopifnot(length(grep("'branch' must be a S4 class git_branch",
+                      res[[1]]$message)) > 0)
+res <- tools::assertError(.Call(git2r:::git2r_branch_delete, repo))
+stopifnot(length(grep("'branch' must be a S4 class git_branch",
+                      res[[1]]$message)) > 0)
+b_tmp <- b
+b_tmp@name <- NA_character_
+res <- tools::assertError(.Call(git2r:::git2r_branch_delete, b_tmp))
+stopifnot(length(grep("'branch' must be a S4 class git_branch",
+                      res[[1]]$message)) > 0)
+b_tmp <- b
+b_tmp@type <- NA_integer_
+res <- tools::assertError(.Call(git2r:::git2r_branch_delete, b_tmp))
+stopifnot(length(grep("'branch' must be a S4 class git_branch",
+                      res[[1]]$message)) > 0)
+b_tmp@type <- 3L
+res <- tools::assertError(.Call(git2r:::git2r_branch_delete, b_tmp))
+stopifnot(length(grep("'branch' must be a S4 class git_branch",
+                      res[[1]]$message)) > 0)
+
 ## Delete branch
 branch_delete(b)
 stopifnot(identical(length(branches(repo)), 1L))