Fix merge conflicts

Author: rbranson

.gitignore

@@ -2,3 +2,13 @@
 *.exe
 *.dll
 *.o
+
+# VSCode
+.vscode
+
+# Exclude from upgrade
+upgrade/*.c
+upgrade/*.h
+
+# Exclude upgrade binary
+upgrade/upgrade

.travis.yml

@@ -1,19 +1,41 @@
 language: go
-sudo: required
-dist: trusty
+
+os:
+  - linux
+  - osx
+
+addons:
+  apt:
+    update: true
+
 env:
-  - GOTAGS=
-  - GOTAGS=libsqlite3
-  - GOTAGS=trace
-  - GOTAGS=vtable
+  matrix:
+    - GOTAGS=
+    - GOTAGS=libsqlite3
+    - GOTAGS="sqlite_allow_uri_authority sqlite_app_armor sqlite_foreign_keys sqlite_fts5 sqlite_icu sqlite_introspect sqlite_json sqlite_secure_delete sqlite_see sqlite_stat4 sqlite_trace sqlite_userauth sqlite_vacuum_incr sqlite_vtable"
+    - GOTAGS=sqlite_vacuum_full
+
 go:
-  - 1.7.x
-  - 1.8.x
   - 1.9.x
-  - master
+  - 1.10.x
+
 before_install:
-  - go get github.com/mattn/goveralls
-  - go get golang.org/x/tools/cmd/cover
+  - |
+    if [[ "$TRAVIS_OS_NAME" == "osx" ]]; then 
+      brew update
+      brew upgrade icu4c
+    fi
+  - |
+    go get github.com/smartystreets/goconvey
+    if [[ "${GOOS}" != "windows" ]]; then
+      go get github.com/mattn/goveralls
+      go get golang.org/x/tools/cmd/cover
+    fi
+
 script:
-  - $HOME/gopath/bin/goveralls -repotoken 3qJVUE0iQwqnCbmNcDsjYu1nh4J4KIFXx
-  - go test -race -v . -tags "$GOTAGS"
+  - GOOS=$(go env GOOS) GOARCH=$(go env GOARCH) go build -v -tags "${GOTAGS}" .
+  - |
+    if [[ "${GOOS}" != "windows" ]]; then
+      $HOME/gopath/bin/goveralls -repotoken 3qJVUE0iQwqnCbmNcDsjYu1nh4J4KIFXx
+      go test -race -v . -tags "${GOTAGS}"
+    fi

README.md

@@ -350,8 +350,18 @@ func callbackRetText(ctx *C.sqlite3_context, v reflect.Value) error {
 	return nil
 }
 
+func callbackRetNil(ctx *C.sqlite3_context, v reflect.Value) error {
+	return nil
+}
+
 func callbackRet(typ reflect.Type) (callbackRetConverter, error) {
 	switch typ.Kind() {
+	case reflect.Interface:
+		errorInterface := reflect.TypeOf((*error)(nil)).Elem()
+		if typ.Implements(errorInterface) {
+			return callbackRetNil, nil
+		}
+		fallthrough
 	case reflect.Slice:
 		if typ.Elem().Kind() != reflect.Uint8 {
 			return nil, errors.New("the only supported slice type is []byte")