DynamicState::update_equal() will return index of next value

opm/parser/eclipse/EclipseState/Schedule/DynamicState.hpp

@@ -21,10 +21,11 @@
 #ifndef DYNAMICSTATE_HPP_
 #define DYNAMICSTATE_HPP_
 
-#include <stdexcept>
-#include <vector>
 #include <algorithm>
+#include <optional>
+#include <stdexcept>
 #include <utility>
+#include <vector>
 
 #include <opm/parser/eclipse/EclipseState/Schedule/TimeMap.hpp>
 
@@ -155,25 +156,26 @@ class DynamicState {
       Schedule object, if e.g. a well is initially closed in the interval
       [T1,T2] and then opened at time T1 < Tx < T2 then the open should be
       applied for all times in the range [Tx,T2].
+
+      The return value is the index of the first element different from value,
+      or an empty optional if there is no such element.
     */
-    void update_equal(size_t index, const T& value) {
+    std::optional<std::size_t> update_equal(size_t index, const T& value) {
         if (this->m_data.size() <= index)
             throw std::out_of_range("Invalid index for update_equal()");
 
         const T prev_value = this->m_data[index];
-        if (prev_value == value)
-            return;
-
+        //if (prev_value == value)
+        //    return {};
         while (true) {
             if (this->m_data[index] != prev_value)
-                break;
+                return index;
 
             this->m_data[index] = value;
 
             index++;
             if (index == this->m_data.size())
-                break;
-
+                return {};
         }
     }
 

tests/parser/DynamicStateTests.cpp

@@ -265,15 +265,21 @@ BOOST_AUTO_TEST_CASE( update_equal ) {
     BOOST_CHECK_EQUAL(state[4], 50);
     BOOST_CHECK_EQUAL(state[5], 100);
 
-    state.update_equal(4,50);
-    BOOST_CHECK_EQUAL(state[4], 50);
-    BOOST_CHECK_EQUAL(state[5], 100);
+    {
+        auto next_index = state.update_equal(4,50);
+        BOOST_CHECK_EQUAL(state[4], 50);
+        BOOST_CHECK_EQUAL(state[5], 100);
+        BOOST_CHECK_EQUAL(next_index.value() , 5);
+    }
 
 
-    state.update_equal(9,200);
-    BOOST_CHECK_EQUAL(state[8] , 100);
-    BOOST_CHECK_EQUAL(state[9] , 200);
-    BOOST_CHECK_EQUAL(state[10], 200);
+    {
+        auto next_index = state.update_equal(9,200);
+        BOOST_CHECK_EQUAL(state[8] , 100);
+        BOOST_CHECK_EQUAL(state[9] , 200);
+        BOOST_CHECK_EQUAL(state[10], 200);
+        BOOST_CHECK(!next_index);
+    }
 }