Update test to cover case using default initial_scale

tests/testthat/test-adaptation.R

@@ -48,7 +48,7 @@ for (target_accept_prob in c(0.2, 0.4, 0.6)) {
             kappa = kappa
           )
           check_adapter(adapter)
-          adapter$initialize(initial_state = chain_state(0))
+          adapter$initialize(initial_state = chain_state(rep(0, dimension)))
           adapter_state <- adapter$state()
           expect_named(adapter_state, "log_scale")
           expect_length(adapter_state$log_scale, 1)
@@ -89,11 +89,24 @@ for (target_accept_prob in c(0.2, 0.4, 0.6)) {
   }
 }
 
-test_that("Scale adapter with only proposal specified works", {
-  proposal <- dummy_proposal_with_scale_parameter()
-  adapter <- scale_adapter(proposal)
-  check_adapter(adapter)
-})
+for (dimension in c(1L, 2L, 5L)) {
+  test_that(
+    sprintf(
+      "Scale adapter with only proposal specified works in dimension %i",
+      dimension
+    ),
+    {
+      proposal <- dummy_proposal_with_scale_parameter()
+      adapter <- scale_adapter(proposal)
+      check_adapter(adapter)
+      adapter$initialize(initial_state = chain_state(rep(0, dimension)))
+      adapter_state <- adapter$state()
+      expect_named(adapter_state, "log_scale")
+      expect_length(adapter_state$log_scale, 1)
+      expect_equal(adapter_state$log_scale, -log(dimension) / 2)
+    }
+  )
+}
 
 for (dimension in c(1L, 2L, 5L)) {
   for (kappa in c(0.5, 0.6, 0.8)) {