Merge pull request #190 from programble/fix/empty-array

Fix empty array conversion

Author: sfackler

src/types/mod.rs

@@ -358,9 +358,11 @@ impl<T: FromSql> FromSql for Vec<T> {
             _ => panic!("expected array type"),
         };
 
-        if try!(raw.read_i32::<BigEndian>()) != 1 {
-            return Err(Error::Conversion("array contains too many dimensions".into()));
-        }
+        match try!(raw.read_i32::<BigEndian>()) {
+            0 => return Ok(Vec::new()),
+            1 => (),
+            _ => return Err(Error::Conversion("array contains too many dimensions".into())),
+        };
 
         let _has_nulls = try!(raw.read_i32::<BigEndian>());
         let _member_oid = try!(raw.read_u32::<BigEndian>());

tests/types/mod.rs

@@ -171,6 +171,14 @@ fn test_hstore_params() {
                 (None, "NULL")]);
 }
 
+#[test]
+fn test_array_params() {
+    test_type("integer[]", &[(Some(vec!(1i32, 2i32)), "ARRAY[1,2]"),
+                             (Some(vec!(1i32)), "ARRAY[1]"),
+                             (Some(vec!()), "ARRAY[]"),
+                             (None, "NULL")]);
+}
+
 fn test_nan_param<T: PartialEq+ToSql+FromSql>(sql_type: &str) {
     let conn = or_panic!(Connection::connect("postgres://postgres@localhost", SslMode::None));
     let stmt = or_panic!(conn.prepare(&*format!("SELECT 'NaN'::{}", sql_type)));