Check for adjoint order before test

R/generate_dust.R

@@ -380,8 +380,16 @@ generate_dust_core_info <- function(dat, rewrite) {
   len <- generate_dust_core_info_len(nms_variable, nms_output, dat, rewrite)
   body$add(sprintf("size_t len = %s;", len))
 
+  if (dat$features$has_derivative) {
+    body$add(sprintf("cpp11::writable::strings adjoint({%s});",
+                     paste(dquote(dat$derivative$parameters), collapse = ", ")))
+  }
+
   body$add("using namespace cpp11::literals;")
   body$add("return cpp11::writable::list({")
+  if (dat$features$has_derivative) {
+    body$add('         "adjoint"_nm = adjoint,')
+  }
   body$add('         "dim"_nm = dim,')
   body$add('         "len"_nm = len,')
   body$add('         "index"_nm = index});')

tests/testthat/test-differentiate.R

@@ -9,10 +9,18 @@ test_that("sir adjoint model works", {
   pars <- list(beta = 0.25, gamma = 0.1, I0 = 1)
   mod <- gen$new(pars, 0, 1, deterministic = TRUE)
   mod$set_data(d)
+
+  ## This is the current temporary arrangement with dust and may change:
+  info <- mod$info()
+  expect_setequal(info$adjoint, c("beta", "gamma", "I0"))
+
   res <- mod$run_adjoint()
 
   expect_equal(res$log_likelihood, -44.0256051296862, tolerance = 1e-14)
+  expect_equal(names(res$gradient), info$adjoint)
   expect_equal(res$gradient,
-               c(244.877646917118, -140.566517375877, 25.2152128116894),
+               c(beta = 244.877646917118,
+                 gamma = -140.566517375877,
+                 I0 = 25.2152128116894)[info$adjoint],
                tolerance = 1e-14)
 })