From 9182031cb173f467d1d293c1e7853eb0e2681f5c Mon Sep 17 00:00:00 2001
From: Nathan Fox <fuchsnj@gmail.com>
Date: Tue, 4 Oct 2022 14:42:25 -0400
Subject: [PATCH] enhancement(vrl): use `undefined` when merging instead of
 `null` (#14670)

use undefined when merging instead of null
---
 lib/value/src/kind/collection.rs                       | 10 +++++-----
 lib/value/src/kind/merge.rs                            |  8 ++++----
 .../if_statement/conditional_assignment.vrl            |  4 ++--
 .../tests/expressions/if_statement/if_else_object.vrl  |  8 ++++----
 4 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/lib/value/src/kind/collection.rs b/lib/value/src/kind/collection.rs
index 03f2fae2f0f6b..0df97f50ef4f6 100644
--- a/lib/value/src/kind/collection.rs
+++ b/lib/value/src/kind/collection.rs
@@ -229,7 +229,7 @@ impl<T: Ord + Clone> Collection<T> {
                 }
             } else if !overwrite {
                 // other is missing this field, which returns null
-                self_kind.add_null();
+                self_kind.add_undefined();
             }
         }
 
@@ -246,7 +246,7 @@ impl<T: Ord + Clone> Collection<T> {
         } else {
             for (key, other_kind) in other.known {
                 // self is missing this field, which returns null
-                self.known.insert(key, other_kind.or_null());
+                self.known.insert(key, other_kind.or_undefined());
             }
         }
         self.unknown.merge(other.unknown, overwrite);
@@ -530,8 +530,8 @@ mod tests {
                     other: Collection::from(BTreeMap::from([("bar", Kind::bytes())])),
                     overwrite: false,
                     want: Collection::from(BTreeMap::from([
-                        ("foo", Kind::integer().or_null()),
-                        ("bar", Kind::bytes().or_null()),
+                        ("foo", Kind::integer().or_undefined()),
+                        ("bar", Kind::bytes().or_undefined()),
                     ])),
                 },
             ),
@@ -558,7 +558,7 @@ mod tests {
                     overwrite: false,
                     want: Collection::from(BTreeMap::from([
                         ("foo", Kind::integer().or_bytes()),
-                        ("bar", Kind::boolean().or_null()),
+                        ("bar", Kind::boolean().or_undefined()),
                     ])),
                 },
             ),
diff --git a/lib/value/src/kind/merge.rs b/lib/value/src/kind/merge.rs
index 99d41e4b0a5ec..63e40687946a8 100644
--- a/lib/value/src/kind/merge.rs
+++ b/lib/value/src/kind/merge.rs
@@ -257,12 +257,12 @@ mod tests {
                             Kind::object(BTreeMap::from([
                                 ("qux".into(), Kind::bytes().or_integer()),
                                 ("quux".into(), Kind::boolean().or_regex()),
-                                ("this".into(), Kind::timestamp().or_null()),
-                                ("that".into(), Kind::null()),
+                                ("this".into(), Kind::timestamp().or_undefined()),
+                                ("that".into(), Kind::null().or_undefined()),
                             ])),
                         ),
-                        ("bar".into(), Kind::integer().or_null()),
-                        ("baz".into(), Kind::boolean().or_null()),
+                        ("bar".into(), Kind::integer().or_undefined()),
+                        ("baz".into(), Kind::boolean().or_undefined()),
                     ])),
                 },
             ),
diff --git a/lib/vrl/tests/tests/expressions/if_statement/conditional_assignment.vrl b/lib/vrl/tests/tests/expressions/if_statement/conditional_assignment.vrl
index c72e3434ec4d6..78e2baf755e57 100644
--- a/lib/vrl/tests/tests/expressions/if_statement/conditional_assignment.vrl
+++ b/lib/vrl/tests/tests/expressions/if_statement/conditional_assignment.vrl
@@ -1,7 +1,7 @@
 # result: {
 #    "object": {
-#       "x": { "boolean": true, "null": true },
-#       "y": { "bytes": true, "null": true }
+#       "x": { "boolean": true, "undefined": true },
+#       "y": { "bytes": true, "undefined": true }
 #    }
 # }
 
diff --git a/lib/vrl/tests/tests/expressions/if_statement/if_else_object.vrl b/lib/vrl/tests/tests/expressions/if_statement/if_else_object.vrl
index 30b2921619765..cbc2663914a7e 100644
--- a/lib/vrl/tests/tests/expressions/if_statement/if_else_object.vrl
+++ b/lib/vrl/tests/tests/expressions/if_statement/if_else_object.vrl
@@ -1,12 +1,12 @@
 # result: {
 #   "x": {},
-#   "x_type": { "object": {"foo": {"boolean": true, "null": true }}},
+#   "x_type": { "object": {"foo": {"boolean": true, "undefined": true }}},
 #   "y": { "foo": true },
-#   "y_type": { "object": {"foo": {"boolean": true, "null": true }}},
+#   "y_type": { "object": {"foo": {"boolean": true, "undefined": true }}},
 #   "x2": {},
-#   "x2_type": { "object": {"foo": {"boolean": true, "null": true }}},
+#   "x2_type": { "object": {"foo": {"boolean": true, "undefined": true }}},
 #   "y2": { "foo": true },
-#   "y2_type": { "object": {"foo": {"boolean": true, "null": true }}}
+#   "y2_type": { "object": {"foo": {"boolean": true, "undefined": true }}}
 # }
 
 .x = if true {