From 6da5cffd87bf44fcc33045121f4c8fb8565edbf3 Mon Sep 17 00:00:00 2001
From: Bill Denney <wdenney@humanpredictions.com>
Date: Tue, 18 Oct 2022 21:40:08 -0400
Subject: [PATCH] Allow duplicated PPSTRESU

---
 R/unit-support.R                   |  3 ++-
 tests/testthat/test-unit-support.R | 12 ++++++++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/R/unit-support.R b/R/unit-support.R
index 67d8d48a..86cbabe4 100644
--- a/R/unit-support.R
+++ b/R/unit-support.R
@@ -67,7 +67,8 @@ pknca_units_table <- function(concu, doseu, amountu, timeu, conversions=data.fra
   }
   if (nrow(conversions) > 0) {
     stopifnot(!duplicated(conversions$PPORRESU))
-    stopifnot(!duplicated(conversions$PPSTRESU))
+    # PPSTRESU may be duplicated because some differing original units may
+    # converge (e.g. cmax.dn and vss)
     stopifnot(length(setdiff(names(conversions), c("PPORRESU", "PPSTRESU", "conversion_factor"))) == 0)
     if (!("conversion_factor" %in% names(conversions))) {
       if (!requireNamespace("units", quietly=TRUE)) {
diff --git a/tests/testthat/test-unit-support.R b/tests/testthat/test-unit-support.R
index 46e4ebeb..9eb6a90f 100644
--- a/tests/testthat/test-unit-support.R
+++ b/tests/testthat/test-unit-support.R
@@ -155,3 +155,15 @@ test_that("pknca_units_table treats missing, NULL, and NA the same", {
       dplyr::pull("PPORRESU")
   )))
 })
+
+test_that("allow duplicate PPSTRESU units", {
+  d_conversion <-
+    data.frame(
+      PPORRESU = c("ng/mL", "(ng/mL)/(mg/kg)", "(mg/kg)/(hr*ng/mL)", "(mg/kg)/(ng/mL)"),
+      PPSTRESU = c("mg/mL", "mL/kg", "mL/(h*kg)", "mL/kg")
+    )
+  # No error for consistent volume conversion
+  expect_silent(
+    pknca_units_table(concu = "ng/mL", doseu = "mg/kg", timeu = "hr", conversions = d_conversion)
+  )
+})