From 273e37102f40c4ede8da9f41ab77ea846752b2fd Mon Sep 17 00:00:00 2001
From: johnabass <johnbass1017@yahoo.com>
Date: Fri, 16 Jun 2023 15:17:28 -0700
Subject: [PATCH] added a basic tag builder as a compiler-friendly alternative
 to specifying tags in annotations

---
 tagBuilder.go      | 73 ++++++++++++++++++++++++++++++++++++++++++++++
 tagBuilder_test.go | 57 ++++++++++++++++++++++++++++++++++++
 2 files changed, 130 insertions(+)
 create mode 100644 tagBuilder.go
 create mode 100644 tagBuilder_test.go

diff --git a/tagBuilder.go b/tagBuilder.go
new file mode 100644
index 0000000..514c846
--- /dev/null
+++ b/tagBuilder.go
@@ -0,0 +1,73 @@
+package arrange
+
+import (
+	"reflect"
+	"strings"
+
+	"go.uber.org/fx"
+)
+
+type TagBuilder struct {
+	tags []string
+}
+
+func (tb *TagBuilder) Skip() *TagBuilder {
+	tb.tags = append(tb.tags, "")
+	return tb
+}
+
+func (tb *TagBuilder) Optional() *TagBuilder {
+	tb.tags = append(tb.tags, `optional:"true"`)
+	return tb
+}
+
+func (tb *TagBuilder) Name(v string) *TagBuilder {
+	var o strings.Builder
+	o.WriteString(`name:"`)
+	o.WriteString(v)
+	o.WriteRune('"')
+	tb.tags = append(tb.tags, o.String())
+
+	return tb
+}
+
+func (tb *TagBuilder) OptionalName(v string) *TagBuilder {
+	var o strings.Builder
+	o.WriteString(`name:"`)
+	o.WriteString(v)
+	o.WriteString(`" optional:"true"`)
+	tb.tags = append(tb.tags, o.String())
+
+	return tb
+}
+
+func (tb *TagBuilder) Group(v string) *TagBuilder {
+	var o strings.Builder
+	o.WriteString(`group:"`)
+	o.WriteString(v)
+	o.WriteRune('"')
+	tb.tags = append(tb.tags, o.String())
+
+	return tb
+}
+
+func (tb *TagBuilder) StructTags() (tags []reflect.StructTag) {
+	tags = make([]reflect.StructTag, 0, len(tb.tags))
+	for _, v := range tb.tags {
+		tags = append(tags, reflect.StructTag(v))
+	}
+
+	return
+}
+
+func (tb *TagBuilder) ParamTags() fx.Annotation {
+	return fx.ParamTags(tb.tags...)
+}
+
+func (tb *TagBuilder) ResultTags() fx.Annotation {
+	return fx.ResultTags(tb.tags...)
+}
+
+func Tags() *TagBuilder {
+	return new(TagBuilder)
+}
diff --git a/tagBuilder_test.go b/tagBuilder_test.go
new file mode 100644
index 0000000..cf15575
--- /dev/null
+++ b/tagBuilder_test.go
@@ -0,0 +1,57 @@
+package arrange
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/stretchr/testify/suite"
+	"go.uber.org/fx"
+	"go.uber.org/fx/fxtest"
+)
+
+type TagBuilderSuite struct {
+	suite.Suite
+}
+
+func (suite *TagBuilderSuite) TestParamTags() {
+	type parameters struct {
+		fx.Out
+
+		Named  string   `name:"name"`
+		Values []string `group:"values"`
+	}
+
+	var buffer *bytes.Buffer
+	app := fxtest.New(
+		suite.T(),
+		fx.Provide(
+			func() parameters {
+				return parameters{} // doesn't matter what the values are
+			},
+			func() int { return 123 },
+			fx.Annotate(
+				func(
+					name string, optional string, values []string, optionalUnnamed string, skipped int,
+				) *bytes.Buffer {
+					return new(bytes.Buffer) // dummy component
+				},
+				Tags().
+					Name("name").
+					OptionalName("optional").
+					Group("values").
+					Optional().
+					Skip().
+					ParamTags(),
+			),
+		),
+		fx.Populate(&buffer), // force the constructor to run
+	)
+
+	app.RequireStart()
+	app.RequireStop()
+	suite.NotNil(buffer)
+}
+
+func TestTagBuilder(t *testing.T) {
+	suite.Run(t, new(TagBuilderSuite))
+}