Keep PostgreSQL casts attached to named parameters

named.go

@@ -336,10 +336,47 @@ func compileNamedQuery(qs []byte, bindType int) (query string, names []string, e
 	last := len(qs) - 1
 	currentVar := 1
 	name := make([]byte, 0, 10)
+	skipNext := false
+
+	appendNamedBind := func() {
+		names = append(names, string(name))
+		switch bindType {
+		// oracle only supports named type bind vars even for positional
+		case NAMED:
+			rebound = append(rebound, ':')
+			rebound = append(rebound, name...)
+		case QUESTION, UNKNOWN:
+			rebound = append(rebound, '?')
+		case DOLLAR:
+			rebound = append(rebound, '$')
+			for _, nb := range strconv.Itoa(currentVar) {
+				rebound = append(rebound, byte(nb))
+			}
+			currentVar++
+		case AT:
+			rebound = append(rebound, '@', 'p')
+			for _, nb := range strconv.Itoa(currentVar) {
+				rebound = append(rebound, byte(nb))
+			}
+			currentVar++
+		}
+	}
 
 	for i, b := range qs {
-		// a ':' while we're in a name is an error
+		if skipNext {
+			skipNext = false
+			continue
+		}
+		// a ':' while we're in a name is an error, except PostgreSQL casts
 		if b == ':' {
+			// :name::type is a named param followed by a PostgreSQL type cast
+			if inName && len(name) > 0 && i < last && qs[i+1] == ':' {
+				appendNamedBind()
+				rebound = append(rebound, ':', ':')
+				inName = false
+				skipNext = true
+				continue
+			}
 			// if this is the second ':' in a '::' escape sequence, append a ':'
 			if inName && i > 0 && qs[i-1] == ':' {
 				rebound = append(rebound, ':')
@@ -367,29 +404,7 @@ func compileNamedQuery(qs []byte, bindType int) (query string, names []string, e
 			if i == last && unicode.IsOneOf(allowedBindRunes, rune(b)) {
 				name = append(name, b)
 			}
-			// add the string representation to the names list
-			names = append(names, string(name))
-			// add a proper bindvar for the bindType
-			switch bindType {
-			// oracle only supports named type bind vars even for positional
-			case NAMED:
-				rebound = append(rebound, ':')
-				rebound = append(rebound, name...)
-			case QUESTION, UNKNOWN:
-				rebound = append(rebound, '?')
-			case DOLLAR:
-				rebound = append(rebound, '$')
-				for _, b := range strconv.Itoa(currentVar) {
-					rebound = append(rebound, byte(b))
-				}
-				currentVar++
-			case AT:
-				rebound = append(rebound, '@', 'p')
-				for _, b := range strconv.Itoa(currentVar) {
-					rebound = append(rebound, byte(b))
-				}
-				currentVar++
-			}
+			appendNamedBind()
 			// add this byte to string unless it was not part of the name
 			if i != last {
 				rebound = append(rebound, b)

named_test.go

@@ -53,6 +53,23 @@ func TestCompileQuery(t *testing.T) {
 			T: `SELECT @name := "name", @p1, @p2, @p3`,
 			V: []string{"age", "first", "last"},
 		},
+		// PostgreSQL type cast immediately after a named parameter (#983)
+		{
+			Q: `SELECT :boundary::jsonb AS boundary`,
+			R: `SELECT ?::jsonb AS boundary`,
+			D: `SELECT $1::jsonb AS boundary`,
+			T: `SELECT @p1::jsonb AS boundary`,
+			N: `SELECT :boundary::jsonb AS boundary`,
+			V: []string{"boundary"},
+		},
+		{
+			Q: `SELECT :a::uuid, :b::text`,
+			R: `SELECT ?::uuid, ?::text`,
+			D: `SELECT $1::uuid, $2::text`,
+			T: `SELECT @p1::uuid, @p2::text`,
+			N: `SELECT :a::uuid, :b::text`,
+			V: []string{"a", "b"},
+		},
 		/* This unicode awareness test sadly fails, because of our byte-wise worldview.
 		 * We could certainly iterate by Rune instead, though it's a great deal slower,
 		 * it's probably the RightWay(tm)
@@ -121,6 +138,36 @@ func (t Test) Errorf(err error, format string, args ...interface{}) {
 	}
 }
 
+func TestNamedPostgresTypeCast(t *testing.T) {
+	q, args, err := Named(
+		`SELECT :boundary::jsonb AS boundary, :id::int AS id`,
+		map[string]interface{}{
+			"boundary": `{"type":"Polygon"}`,
+			"id":       7,
+		},
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+	want := `SELECT ?::jsonb AS boundary, ?::int AS id`
+	if q != want {
+		t.Errorf("query:\n got: %s\nwant: %s", q, want)
+	}
+	if len(args) != 2 {
+		t.Fatalf("got %d args, want 2: %#v", len(args), args)
+	}
+	if args[0] != `{"type":"Polygon"}` || args[1] != 7 {
+		t.Errorf("args: %#v", args)
+	}
+}
+
+func TestNamedParamSingleColonStillErrors(t *testing.T) {
+	_, _, err := compileNamedQuery([]byte("SELECT :first:name"), QUESTION)
+	if err == nil {
+		t.Fatal("expected error for a single colon inside a named param")
+	}
+}
+
 func TestEscapedColons(t *testing.T) {
 	t.Skip("not sure it is possible to support this in general case without an SQL parser")
 	var qs = `SELECT * FROM testtable WHERE timeposted BETWEEN (now() AT TIME ZONE 'utc') AND