From 6f3d3f62de96ef32efd1d606797a3e92a4a67afb Mon Sep 17 00:00:00 2001
From: Romain Goyet <romain.goyet@numworks.com>
Date: Wed, 11 Mar 2020 10:36:38 -0400
Subject: [PATCH] [python/matplotlib] Validate the plot parameters

---
 python/port/mod/matplotlib/modpyplot.cpp  | 16 +++++++++++++---
 python/port/mod/matplotlib/plot_store.cpp |  3 ---
 python/port/mod/matplotlib/plot_store.h   |  2 +-
 3 files changed, 14 insertions(+), 7 deletions(-)

diff --git a/python/port/mod/matplotlib/modpyplot.cpp b/python/port/mod/matplotlib/modpyplot.cpp
index 482afe24d..2f9e91430 100644
--- a/python/port/mod/matplotlib/modpyplot.cpp
+++ b/python/port/mod/matplotlib/modpyplot.cpp
@@ -35,7 +35,8 @@ void modpyplot_gc_collect() {
  * Returns : xmin, xmax, ymin, ymax : float */
 
 mp_obj_t modpyplot_axis(mp_obj_t arg) {
-  mp_obj_is_type(arg, &mp_type_enumerate);
+  assert(sPlotStore != nullptr);
+
 #warning Use mp_obj_is_bool when upgrading uPy
   if (mp_obj_is_type(arg, &mp_type_bool)) {
     sPlotStore->setGrid(mp_obj_is_true(arg));
@@ -59,9 +60,18 @@ mp_obj_t modpyplot_axis(mp_obj_t arg) {
 
 mp_obj_t modpyplot_plot(mp_obj_t x, mp_obj_t y) {
   assert(sPlotStore != nullptr);
+
+  // Input parameter validation
+  size_t xLength, yLength;
+  mp_obj_t * xItems, yItems;
+  mp_obj_get_array(x, &xLength, &xItems);
+  mp_obj_get_array(y, &yLength, &yItems);
+  if (xLength != yLength) {
+    mp_raise_msg_varg(&mp_type_ValueError, "x and y must have same dimension");
+  }
+
   sPlotStore->addDots(x, y);
-  // Ensure x and y are arrays
-  // "Push" x and y on bigger arrays
+
   return mp_const_none;
 }
 
diff --git a/python/port/mod/matplotlib/plot_store.cpp b/python/port/mod/matplotlib/plot_store.cpp
index 681077f44..075174d20 100644
--- a/python/port/mod/matplotlib/plot_store.cpp
+++ b/python/port/mod/matplotlib/plot_store.cpp
@@ -16,9 +16,6 @@ void PlotStore::addDots(mp_obj_t x, mp_obj_t y) {
   mp_obj_t items[2] = {x, y};
   mp_obj_t tuple = mp_obj_new_tuple(2, items);
   mp_obj_list_append(m_dots, tuple);
-
-  //mp_obj_tuple_t * t = static_cast<mp_obj_tuple_t *>(MP_OBJ_TO_PTR(mp_obj_new_tuple(3, NULL)));
-  //t->items[0] = MP_OBJ_NEW_SMALL_INT(r);
 }
 
 PlotStore::Dot PlotStore::dotAtIndex(int i) {
diff --git a/python/port/mod/matplotlib/plot_store.h b/python/port/mod/matplotlib/plot_store.h
index 1cca7b3b9..5b76c53a4 100644
--- a/python/port/mod/matplotlib/plot_store.h
+++ b/python/port/mod/matplotlib/plot_store.h
@@ -35,7 +35,7 @@ public:
   void setGrid(bool grid) { m_grid = grid; }
   bool grid() { return m_grid; }
 private:
-  mp_obj_t m_dots;
+  mp_obj_t m_dots; // A list of (x,y), where x and y are lists of numbers
   bool m_grid;
 
   /*