add new scoped vector invariants

src/util/scoped_vector.h

@@ -176,8 +176,46 @@ class scoped_vector {
     }
 
     bool invariant() const {
-        return 
-            m_size <= m_elems.size() &&
-            m_elems_start <= m_elems.size();
+
+
+        if (!(m_size <= m_elems.size() && m_elems_start <= m_elems.size()))
+            return false;
+
+        // Check that source and destination trails have the same length.
+        if (m_src.size() != m_dst.size())
+            return false;
+        // The size of m_src, m_dst, and m_src_lim should be consistent with the scope stack.
+        if (m_src_lim.size() != m_sizes.size() || m_src.size() != m_dst.size())
+            return false;
+
+        // m_elems_lim stores the past sizes of m_elems for each scope. Each element in m_elems_lim should be
+        // within bounds and in non-decreasing order.
+        for (unsigned i = 1; i < m_elems_lim.size(); ++i) {
+            if (m_elems_lim[i - 1] > m_elems_lim[i]) return false;
+        }
+
+
+        // m_sizes tracks the size of the vector at each scope level.
+        // Each element in m_sizes should be non-decreasing and within the size of m_elems.
+        for (unsigned i = 1; i < m_sizes.size(); ++i) {
+            if (m_sizes[i - 1] > m_sizes[i])
+                return false;
+        }
+
+        // The m_src and m_dst vectors should have the same size and should contain valid indices.
+        if (m_src.size() != m_dst.size()) return false;
+        for (unsigned i = 0; i < m_src.size(); ++i) {
+            if (m_src[i] >= m_index.size() || m_dst[i] >= m_elems.size()) return false;
+        }
+
+
+        // The size of m_src_lim should be less than or equal to the size of m_sizes and store valid indices.
+        if (m_src_lim.size() > m_sizes.size()) return false;
+        for (unsigned elem : m_src_lim) {
+            if (elem > m_src.size()) return false;
+        }
+
+        return true;
+
     }
 };