Merge pull request #134 from mrc-ide/mrc-6118

Fix error while generating odin model

DESCRIPTION

@@ -1,6 +1,6 @@
 Package: odin2
 Title: Next generation odin
-Version: 0.3.14
+Version: 0.3.15
 Authors@R: c(person("Rich", "FitzJohn", role = c("aut", "cre"),
                     email = "[email protected]"),
              person("Wes", "Hinsley", role = "aut"),

R/dependencies.R

@@ -3,9 +3,12 @@ find_dependencies <- function(expr) {
   variables <- collector()
   descend <- function(e) {
     if (is.recursive(e)) {
-      nm <- deparse(e[[1L]])
-      functions$add(nm)
-      if (nm %in% c("length", "dim") && length(e) == 2 && is.symbol(e[[2]])) {
+      if (rlang::is_call(e) && is.symbol(e[[1]])) {
+        functions$add(deparse(e[[1L]]))
+      }
+      is_dim_read <- rlang::is_call(e, c("length", "dim")) &&
+        length(e) == 2 && is.symbol(e[[2]])
+      if (is_dim_read) {
         variables$add(odin_dim_name(deparse(e[[2]])))
       } else {
         for (el in as.list(e[-1])) {

tests/testthat/test-dependencies.R

@@ -41,3 +41,17 @@ test_that("can join dependencies", {
     list(functions = c("a", "f", "g", "h", "i"),
          variables = c("a", "b", "c", "d", "e")))
 })
+
+
+test_that("cope with poorly deparsing epxressions", {
+  expr <- quote(
+    OdinStochasticCall(
+      sample = "binomial",
+      mean = S_leave[i, j, k] * (S_rates[i, j, k, 1] / S_leave_rate[i, j, k])
+    )(S_leave[i, j, k], S_rates[i, j, k, 1]/S_leave_rate[i, j, k]))
+  res <- find_dependencies(expr)
+  expect_setequal(res$functions, c("[", "/"))
+  expect_setequal(
+    res$variables,
+    c("S_leave", "i", "j", "k", "S_rates", "S_leave_rate"))
+})