From 6315525dbef08bac66b6369f7d6952b67b5adcba Mon Sep 17 00:00:00 2001
From: Cody Peter Mello <melloc@writev.io>
Date: Sun, 23 Sep 2018 17:59:52 -0700
Subject: [PATCH] Rebuild fields when NF is assigned to itself

---
 bugs-fixed/README             | 2 ++
 bugs-fixed/nf-self-assign.awk | 6 ++++++
 bugs-fixed/nf-self-assign.bad | 1 +
 bugs-fixed/nf-self-assign.ok  | 1 +
 run.c                         | 4 ++--
 5 files changed, 12 insertions(+), 2 deletions(-)
 create mode 100644 bugs-fixed/nf-self-assign.awk
 create mode 100644 bugs-fixed/nf-self-assign.bad
 create mode 100644 bugs-fixed/nf-self-assign.ok

diff --git a/bugs-fixed/README b/bugs-fixed/README
index 222ef68..29c845f 100644
--- a/bugs-fixed/README
+++ b/bugs-fixed/README
@@ -23,3 +23,5 @@ and also if CONVFMT changed.
 
 7. unary-plus: Unary plus on a string constant returned the string.
 Instead, it should convert the value to numeric and give that value.
+
+X. nf-self-assign: "NF = NF" wouldn't force the record to be rebuilt.
diff --git a/bugs-fixed/nf-self-assign.awk b/bugs-fixed/nf-self-assign.awk
new file mode 100644
index 0000000..6ae29ee
--- /dev/null
+++ b/bugs-fixed/nf-self-assign.awk
@@ -0,0 +1,6 @@
+BEGIN {
+	$0="a b c";
+	OFS=",";
+	NF = NF;
+	print;
+}
diff --git a/bugs-fixed/nf-self-assign.bad b/bugs-fixed/nf-self-assign.bad
new file mode 100644
index 0000000..3774da6
--- /dev/null
+++ b/bugs-fixed/nf-self-assign.bad
@@ -0,0 +1 @@
+a b c
diff --git a/bugs-fixed/nf-self-assign.ok b/bugs-fixed/nf-self-assign.ok
new file mode 100644
index 0000000..b2ffb02
--- /dev/null
+++ b/bugs-fixed/nf-self-assign.ok
@@ -0,0 +1 @@
+a,b,c
diff --git a/run.c b/run.c
index 81b75da..14a0c74 100644
--- a/run.c
+++ b/run.c
@@ -1117,8 +1117,8 @@ Cell *assign(Node **a, int n)	/* a[0] = a[1], a[0] += a[1], etc. */
 	y = execute(a[1]);
 	x = execute(a[0]);
 	if (n == ASSIGN) {	/* ordinary assignment */
-		if (x == y && !(x->tval & (FLD|REC)))	/* self-assignment: */
-			;		/* leave alone unless it's a field */
+		if (x == y && !(x->tval & (FLD|REC)) && x != nfloc)
+			;	/* self-assignment: leave alone unless it's a field or NF */
 		else if ((y->tval & (STR|NUM)) == (STR|NUM)) {
 			setsval(x, getsval(y));
 			x->fval = getfval(y);