From 431015e9689021b316ec9ec26fba5a1b4b9a3f83 Mon Sep 17 00:00:00 2001
From: Noah Treuhaft <noah.treuhaft@gmail.com>
Date: Thu, 15 Oct 2026 13:37:03 -0400
Subject: [PATCH 1/2] sio/csvio: fix missing field output

The CSV writer emits "none" for a missing field like the one in
{a:none::(int64|none)}.  Emit an empty string instead.
---
 sio/csvio/writer.go        | 24 +++++++++++-------------
 sio/csvio/ztests/none.yaml |  9 +++++++++
 2 files changed, 20 insertions(+), 13 deletions(-)
 create mode 100644 sio/csvio/ztests/none.yaml

diff --git a/sio/csvio/writer.go b/sio/csvio/writer.go
index e19e32f221..617d38f74d 100644
--- a/sio/csvio/writer.go
+++ b/sio/csvio/writer.go
@@ -93,19 +93,17 @@ func (w *Writer) Write(rec super.Value) error {
 	for i, it := 0, rec.Bytes().Iter(); i < len(fields) && !it.Done(); i++ {
 		var s string
 		elem := it.Next()
-		if !super.IsNone(fields[i].Type, elem) {
-			val := super.NewValue(fields[i].Type, elem).Under()
-			switch id := val.Type().ID(); {
-			case id == super.IDBytes && len(val.Bytes()) == 0:
-				// We want "" instead of "0x" for a zero-length value.
-			case id == super.IDString:
-				s = string(val.Bytes())
-			case id == super.IDNull:
-			default:
-				s = formatValue(val.Type(), val.Bytes())
-				if super.IsFloat(id) && strings.HasSuffix(s, ".") {
-					s = strings.TrimSuffix(s, ".")
-				}
+		val := super.NewValue(fields[i].Type, elem).Under()
+		switch id := val.Type().ID(); {
+		case id == super.IDBytes && len(val.Bytes()) == 0:
+			// We want "" instead of "0x" for a zero-length value.
+		case id == super.IDString:
+			s = string(val.Bytes())
+		case id == super.IDNull || id == super.IDNone:
+		default:
+			s = formatValue(val.Type(), val.Bytes())
+			if super.IsFloat(id) && strings.HasSuffix(s, ".") {
+				s = strings.TrimSuffix(s, ".")
 			}
 		}
 		w.strings = append(w.strings, s)
diff --git a/sio/csvio/ztests/none.yaml b/sio/csvio/ztests/none.yaml
new file mode 100644
index 0000000000..94a912c46d
--- /dev/null
+++ b/sio/csvio/ztests/none.yaml
@@ -0,0 +1,9 @@
+spq: pass
+
+flags: -f csv
+
+input: |
+  {none:none::(int64|none)}
+
+output: "none\n\
+  \n"

From fe184523f7005903b8ffe7f67534265962a60970 Mon Sep 17 00:00:00 2001
From: Noah Treuhaft <noah.treuhaft@gmail.com>
Date: Thu, 15 Oct 2026 13:53:17 -0400
Subject: [PATCH 2/2] update sio/csvio/ztests/none.yaml

---
 sio/csvio/ztests/none.yaml | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sio/csvio/ztests/none.yaml b/sio/csvio/ztests/none.yaml
index 94a912c46d..f2569b60e6 100644
--- a/sio/csvio/ztests/none.yaml
+++ b/sio/csvio/ztests/none.yaml
@@ -3,7 +3,7 @@ spq: pass
 flags: -f csv
 
 input: |
-  {none:none::(int64|none)}
+  {a:none::(int64|none)}
 
-output: "none\n\
+output: "a\n\
   \n"