🎈 update: add some useful function

.gitignore

@@ -1 +1,2 @@
-bin
+bin
+.vscode

README.md

@@ -6,29 +6,37 @@ Using json file and go template to generate go code.
 
 ## Installation
 
-```
+```bash
 go get github.com/OhYee/gcg
 go install github.com/OhYee/gcg
 ```
 
 ## Usage
 
-```
+```bash
 gcg data.json compare.go
 ```
 
-## document
+## Document
 
 The json file must have these field:
 
 |name|type||
-|:---:|:---:|:---:|
+|:---|:---|:---|
 |package|string|package name|
 |import|`[]string` or `[][]string`|import part of the file|
 |body|`[]strut{template string, args interface{}}` or `[]struct{template []string, args interface{}}`|the go file body|
 
 The `template` and `args` in `body` will be the arguments of go `text/template`
 
+### Function
+
+|name|args||
+|:---|:---|:---|
+|lower|`string`|make all letters to their lower case|
+|upper|`string`|make all letters to their upper case|
+|upperFirstChar|`string`|make the first letter to its upper case, keep others|
+
 ## Example
 
 See [number compare package](https://github.com/OhYee/gcg/tree/master/example/compare), you can delete `compare.go` and using `gcg data.json compare.go` or `go generate g.go` to re-generate it.

README_CN.md

@@ -22,13 +22,21 @@ gcg data.json compare.go
 JSON文件字段要求
 
 |名称|类型||
-|:---:|:---:|:---:|
+|:---|:---|:---|
 |package|string|生成文件的包名|
 |import|`[]string` or `[][]string`|Go文件的引入包部分|
 |body|`[]strut{template string, args interface{}}` or `[]struct{template []string, args interface{}}`|Go文件主体|
 
 `body`的`template` 和 `args` 将用于 Go `text/template` 的参数
 
+### 函数
+
+|名称|参数||
+|:---|:---|:---|
+|lower|`string`|使所有字母小写|
+|upper|`string`|使所有字母大写|
+|upperFirstChar|`string`|使首字母大写|
+
 ## 样例
 
 详情见 [大小比较包](https://github.com/OhYee/gcg/tree/master/example/compare), 你可以先删除 `compare.go` 然后使用 `gcg data.json compare.go` 或者 `go generate g.go` 来重新生成它.

example/compare/data.json

@@ -10,7 +10,7 @@
     ],
     "body": [
         {
-            "template": "const.tpl",
+            "template": "/home/ohyee/projects/gcg/example/compare/const.tpl",
             "args": ["-"]
         },
         {

gcg.go

@@ -5,14 +5,15 @@ import (
 	"encoding/json"
 	"fmt"
 	"go/format"
+	"io"
 	"io/ioutil"
 	"os"
 	"strings"
 	"text/template"
 )
 
 const (
-	version  = "0.0.2"
+	version  = "0.0.3"
 	helpText = "Using `gcg <json file> [<output file>]` to generate go file\nSuch as `gcg data.json` or `gcg data.json ../add.go`"
 )
 
@@ -35,6 +36,18 @@ type bodyArea struct {
 }
 type jsonMap = map[string]interface{}
 
+var funcMap = template.FuncMap{
+	"upperFirstChar": func(text string) string {
+		return fmt.Sprintf("%s%s", strings.ToUpper(text[0:1]), text[1:len(text)])
+	},
+	"upper": func(text string) string {
+		return strings.ToUpper(text)
+	},
+	"lower": func(text string) string {
+		return strings.ToLower(text)
+	},
+}
+
 // exitWhenError exit the program when error is not null
 func exitWhenError(err error) {
 	if err != nil {
@@ -88,28 +101,28 @@ func importPackage(x interface{}) (s string) {
 	return
 }
 
-func main() {
-	var inputFile string
-	var outputFile *os.File
-	switch len(os.Args) {
-	case 1:
-		exitWhenFalse(false, helpText)
-	case 2:
-		if os.Args[1] == "-h" || os.Args[1] == "--help" {
-			exitWhenFalse(false, helpText)
-		} else if os.Args[1] == "-v" || os.Args[1] == "--version" {
-			exitWhenFalse(false, fmt.Sprintf("Go Code Generator version: %s\n", version))
-		}
-		inputFile = os.Args[1]
-		outputFile = os.Stdout
-	default:
-		var err error
-		inputFile = os.Args[1]
-		outputFile, err = os.Create(os.Args[2])
-		exitWhenError(err)
+// getFilename from a path (go template name can not be a path)
+func getFileName(path string) (filename string) {
+	pathList := strings.Split(path, "/")
+	filename = pathList[len(pathList)-1]
+	return
+}
+
+// renderTemplate render the block template
+func renderTemplate(buf io.Writer, templates []string, args []interface{}) {
+	templateName := getFileName(templates[0])
+	tpl, err := template.New(templateName).Funcs(funcMap).ParseFiles(templates...)
+	exitWhenError(err)
+	for _, arg := range args {
+		// tpl.Execute(buf, arg)
+		tpl.ExecuteTemplate(buf, templateName, arg)
+		buf.Write([]byte{'\n'})
 	}
-	args := readData(inputFile)
+}
 
+// renderContent render generated file content
+func renderContent(args arguments) []byte {
+	// header
 	buf := bytes.NewBufferString("// generated by Go Code Generator(https://github.com/OhYee/gcg); DO NOT EDIT\n\n")
 	buf.WriteString(fmt.Sprintf("package %s\n\n", args.PackageName))
 	buf.WriteString(fmt.Sprintf("import (\n%s\n)\n\n",
@@ -127,6 +140,7 @@ func main() {
 		}(args.ImportedPackage),
 	))
 
+	// body
 	for _, block := range args.Body {
 		var templates []string
 		switch block.Template.(type) {
@@ -144,31 +158,39 @@ func main() {
 		default:
 			exitWhenFalse(false, "template must be string or []string")
 		}
-
-		tpl, err := template.New(templates[0]).Funcs(
-			template.FuncMap{
-				"upperFirstChar": func(text string) string {
-					return strings.ToTitle(text)
-				},
-				"upper": func(text string) string {
-					return strings.ToUpper(text)
-				},
-				"lower": func(text string) string {
-					return strings.ToLower(text)
-				},
-			},
-		).ParseFiles(templates...)
-		exitWhenError(err)
-		for _, arg := range block.Args {
-			tpl.Execute(buf, arg)
-			buf.WriteString("\n\n")
-		}
+		renderTemplate(buf, templates, block.Args)
 	}
 
+	// code format
 	b, err := format.Source(buf.Bytes())
 	if err != nil {
 		fmt.Printf("goformat error\n%s\n", err)
 		b = buf.Bytes()
 	}
+	return b
+}
+
+func main() {
+	var inputFile string
+	var outputFile *os.File
+	switch len(os.Args) {
+	case 1:
+		exitWhenFalse(false, helpText)
+	case 2:
+		if os.Args[1] == "-h" || os.Args[1] == "--help" {
+			exitWhenFalse(false, helpText)
+		} else if os.Args[1] == "-v" || os.Args[1] == "--version" {
+			exitWhenFalse(false, fmt.Sprintf("Go Code Generator version: %s\n", version))
+		}
+		inputFile = os.Args[1]
+		outputFile = os.Stdout
+	default:
+		var err error
+		inputFile = os.Args[1]
+		outputFile, err = os.Create(os.Args[2])
+		exitWhenError(err)
+	}
+	args := readData(inputFile)
+	b := renderContent(args)
 	outputFile.Write(b)
 }

gcg_test.go

@@ -0,0 +1,84 @@
+package main
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"testing"
+)
+
+func writeToTempFile(t *testing.T, content string) string {
+	file, err := ioutil.TempFile("", "test")
+	if err != nil {
+		t.Errorf("Create temp file error: %v", err)
+	}
+	_, err = file.WriteString(content)
+	if err != nil {
+		t.Errorf("Write to temp file error: %v", err)
+	}
+	file.Close()
+	return file.Name()
+}
+
+func Test_renderTemplate(t *testing.T) {
+	tests := []struct {
+		name     string
+		template string
+		args     []interface{}
+		result   string
+	}{
+		{
+			name:     "test upper",
+			template: "{{upper .text}}",
+			args: []interface{}{
+				map[string]interface{}{
+					"text": "ABcdefg1234567",
+				},
+			},
+			result: "ABCDEFG1234567\n",
+		},
+		{
+			name:     "test lower",
+			template: "{{lower .text}}",
+			args: []interface{}{
+				map[string]interface{}{
+					"text": "ABcdefg1234567",
+				},
+			},
+			result: "abcdefg1234567\n",
+		},
+		{
+			name:     "test upperFirstChar",
+			template: "{{upperFirstChar .text}}",
+			args: []interface{}{
+				map[string]interface{}{
+					"text": "ABcdefg1234567",
+				},
+			},
+			result: "ABcdefg1234567\n",
+		},
+		{
+			name:     "test upperFirstChar 2",
+			template: "{{upperFirstChar .text}}",
+			args: []interface{}{
+				map[string]interface{}{
+					"text": "abc",
+				},
+			},
+			result: "Abc\n",
+		},
+	}
+
+	buf := bytes.NewBuffer([]byte{})
+	for _, tt := range tests {
+		buf.Reset()
+		filename := writeToTempFile(t, tt.template)
+		t.Run(tt.name, func(t *testing.T) {
+			renderTemplate(buf, []string{filename}, tt.args)
+			if buf.String() != tt.result {
+				t.Errorf("want %v, but got %v", tt.result, buf.String())
+			}
+		})
+		os.Remove(filename)
+	}
+}