Grand test fixup (#138)

* start fixing up tests

* fix up tests + automate with drone

* fiddle with linting

* messing about with drone.yml

* some more fiddling

* hmmm

* add cache

* add vendor directory

* verbose

* ci updates

* update some little things

* update sig

vendor/github.com/go-pg/pg/v10/internal/util.go

@@ -0,0 +1,71 @@
+package internal
+
+import (
+	"context"
+	"reflect"
+	"time"
+)
+
+func Sleep(ctx context.Context, dur time.Duration) error {
+	t := time.NewTimer(dur)
+	defer t.Stop()
+
+	select {
+	case <-t.C:
+		return nil
+	case <-ctx.Done():
+		return ctx.Err()
+	}
+}
+
+func MakeSliceNextElemFunc(v reflect.Value) func() reflect.Value {
+	if v.Kind() == reflect.Array {
+		var pos int
+		return func() reflect.Value {
+			v := v.Index(pos)
+			pos++
+			return v
+		}
+	}
+
+	elemType := v.Type().Elem()
+
+	if elemType.Kind() == reflect.Ptr {
+		elemType = elemType.Elem()
+		return func() reflect.Value {
+			if v.Len() < v.Cap() {
+				v.Set(v.Slice(0, v.Len()+1))
+				elem := v.Index(v.Len() - 1)
+				if elem.IsNil() {
+					elem.Set(reflect.New(elemType))
+				}
+				return elem.Elem()
+			}
+
+			elem := reflect.New(elemType)
+			v.Set(reflect.Append(v, elem))
+			return elem.Elem()
+		}
+	}
+
+	zero := reflect.Zero(elemType)
+	return func() reflect.Value {
+		if v.Len() < v.Cap() {
+			v.Set(v.Slice(0, v.Len()+1))
+			return v.Index(v.Len() - 1)
+		}
+
+		v.Set(reflect.Append(v, zero))
+		return v.Index(v.Len() - 1)
+	}
+}
+
+func Unwrap(err error) error {
+	u, ok := err.(interface {
+		Unwrap() error
+	})
+	if !ok {
+		return nil
+	}
+	return u.Unwrap()
+}