Relax constraint on VALUE clause expansion

This lets it be used in non-INSERT scenarios as well. See the test for
such an example.

Author: cespare

named.go

@@ -224,7 +224,7 @@ func bindStruct(bindType int, query string, arg interface{}, m *reflectx.Mapper)
 	return bound, arglist, nil
 }
 
-var valuesReg = regexp.MustCompile(`\)\s*(?i)VALUES\s*\(`)
+var valuesReg = regexp.MustCompile(`(?i)\WVALUES\s*\(`)
 
 func findMatchingClosingBracketIndex(s string) int {
 	count := 0

named_test.go

@@ -422,6 +422,30 @@ func TestFixBounds(t *testing.T) {
 	)`,
 			loop: 2,
 		},
+		{
+			name: "use of VALUES not for insert",
+			query: `
+UPDATE t
+SET
+  foo = u.foo,
+  bar = u.bar
+FROM (
+  VALUES (:id, :foo, :bar)
+) AS u(id, foo, bar)
+WHERE t.id = u.id
+`,
+			expect: `
+UPDATE t
+SET
+  foo = u.foo,
+  bar = u.bar
+FROM (
+  VALUES (:id, :foo, :bar),(:id, :foo, :bar)
+) AS u(id, foo, bar)
+WHERE t.id = u.id
+`,
+			loop: 2,
+		},
 	}
 
 	for _, tc := range table {