Fix two node-copying bugs in update

FacadeTest.cpp

@@ -1,4 +1,5 @@
 #include "Facade.h"
+#include "PrintMutation.h"
 #include "VersionedMap.h"
 #include <inttypes.h>
 
@@ -24,6 +25,8 @@ weaselab::VersionedMap::Mutation clear(weaselab::VersionedMap::Key begin,
   return {begin.p, end.p, begin.len, end.len, weaselab::VersionedMap::Clear};
 }
 
+void breakpoint_me() {}
+
 int main() {
   Facade f(0);
   int64_t version = 1;
@@ -42,13 +45,14 @@ int main() {
   }
   for (int64_t i = 0; i < version; ++i) {
     printf("--- version %" PRId64 " ---\n", i);
-    auto result = f.viewAt(i).rangeRead("a"_s, "d"_s, 10, false);
+    printf("merged:\n");
+    auto result = f.viewAt(i).rangeRead("a"_s, "z"_s, 100, false);
     for (const auto &[k, v] : result) {
       for (auto c : k) {
         if (isprint(c)) {
           printf("%c", c);
         } else {
-          printf("0x%02x", c);
+          printf("x%02x", c);
         }
       }
       printf(" -> ");
@@ -56,10 +60,35 @@ int main() {
         if (isprint(c)) {
           printf("%c", c);
         } else {
-          printf("0x%02x", c);
+          printf("x%02x", c);
         }
       }
       printf("\n");
     }
+    printf("unversioned:\n");
+    for (const auto &[k, v] : f.unversioned) {
+      for (auto c : k) {
+        if (isprint(c)) {
+          printf("%c", c);
+        } else {
+          printf("x%02x", c);
+        }
+      }
+      printf(" -> ");
+      for (auto c : v) {
+        if (isprint(c)) {
+          printf("%c", c);
+        } else {
+          printf("x%02x", c);
+        }
+      }
+      printf("\n");
+    }
+    breakpoint_me();
+    printf("versioned:\n");
+    for (auto iter = f.versioned.begin(i), end = f.versioned.end(i);
+         iter != end; ++iter) {
+      printMutation(*iter);
+    }
   }
 }