Adding a range checked at() to the iterator view

njoy · Oct 12, 2023 · 39d7d60 · 39d7d60
1 parent 0ab5a13
commit 39d7d60
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diff --git a/src/tools/view/IteratorView.hpp b/src/tools/view/IteratorView.hpp
@@ -3,6 +3,7 @@
 
 // system includes
 #include <iterator>
+#include <stdexcept>
 
 // other includes
 
@@ -109,6 +110,22 @@ class IteratorView {
     return *( std::next( this->begin(), i ) );
   }
 
+  /**
+   *  @brief Return an element at a given index with range checking
+   *
+   *  @param[in] i    the index
+   */
+  constexpr decltype(auto) at( size_type i ) const {
+
+    if ( i >= this->size() ) {
+
+      throw std::out_of_range( "Index out of range: " + std::to_string( i ) +
+                               " >= size (" + std::to_string( this->size() ) +
+                               ")" );
+    }
+    return this->operator[]( i );
+  }
+
   /**
    *  @brief Verify if the IteratorView is equal to another container
    *

diff --git a/src/tools/view/IteratorView/test/IteratorView.test.cpp b/src/tools/view/IteratorView/test/IteratorView.test.cpp
@@ -30,9 +30,24 @@ SCENARIO( "IteratorView" ) {
         CHECK(  1 == chunk[3] );
         CHECK(  2 == chunk[4] );
 
+        CHECK( -2 == chunk.at( 0 ) );
+        CHECK( -1 == chunk.at( 1 ) );
+        CHECK(  0 == chunk.at( 2 ) );
+        CHECK(  1 == chunk.at( 3 ) );
+        CHECK(  2 == chunk.at( 4 ) );
+
         CHECK( -2 == chunk.front() );
         CHECK(  2 == chunk.back() );
       } // THEN
+
+      THEN( "an exception is thrown when using an index that is too large or "
+            "too small" ) {
+
+        CHECK_NOTHROW( chunk.at( 0 ) );
+        CHECK_NOTHROW( chunk.at( 4 ) );
+        CHECK_THROWS( chunk.at( 5 ) );
+        CHECK_THROWS( chunk.at( 10 ) );
+      } // THEN
     } // WHEN
 
     WHEN( "when make functions are used" ) {
@@ -50,9 +65,24 @@ SCENARIO( "IteratorView" ) {
         CHECK(  1 == chunk[3] );
         CHECK(  2 == chunk[4] );
 
+        CHECK( -2 == chunk.at( 0 ) );
+        CHECK( -1 == chunk.at( 1 ) );
+        CHECK(  0 == chunk.at( 2 ) );
+        CHECK(  1 == chunk.at( 3 ) );
+        CHECK(  2 == chunk.at( 4 ) );
+
         CHECK( -2 == chunk.front() );
         CHECK(  2 == chunk.back() );
       } // THEN
+
+      THEN( "an exception is thrown when using an index that is too large or "
+            "too small" ) {
+
+        CHECK_NOTHROW( chunk.at( 0 ) );
+        CHECK_NOTHROW( chunk.at( 4 ) );
+        CHECK_THROWS( chunk.at( 5 ) );
+        CHECK_THROWS( chunk.at( 10 ) );
+      } // THEN
     } // WHEN
   } // GIVEN