Go for VSCode

1. 相关文档文档

主文档
https://github.com/microsoft/vscode-go
扩展工具（extension tools）的介绍和下载方式
https://github.com/Microsoft/vscode-go/wiki/Go-tools-that-the-Go-extension-depends-on
gopls文档
https://github.com/golang/tools/blob/master/gopls/doc/user.md
在VSCode中使用Go的常见问题和解决方式
https://github.com/Microsoft/vscode-go/wiki/Go-with-VS-Code-FAQ-and-Troubleshooting

2 介绍

VSCode使用Go Extensions来为Go的开发提供了丰富的语言支持。

Go Extensions通过使用一组Go Tools来支持相应的语言特性。

由于Go Extensions使用了大量的Go Tools来提供语法特性，因此为了简化大量Go Tools依赖带来的麻烦，使用了单个语法服务来替换这些Go Tools,这个语法服务由 Language Server Protocol（简称LSP）来提供标准，具体实现有Google的gopls、bingo。

gopls是由Google开发的支持Go的语法特性的Language Server，且支持go Modules因此将使用gopls来作为VSCode的Language Server。

下文将根据下列目录来介绍在VSCode中使用Go：

• 使用VSCode开发go
• Go Tools
• gopls
• go Extensions和gopls 配置
• 要注意的地方

3 使用VSCode开发go

1. 在VSCode的Extensions中添加Go插件
   2.在File->Preferences->settings->Extensions->Go Configuration中打开setting.json,写入如下配置

{
    "go.useLanguageServer": true,//使用gopls
    "go.languageServerExperimentalFeatures": {
        "diagnostics": true // for diagnostics as you type
    },
    "[go]": {
        "editor.snippetSuggestions": "none",
        "editor.formatOnSave": true,
        "editor.codeActionsOnSave": {
            "source.organizeImports": true
        },
    },
    "gopls": {
        "usePlaceholders": true // add parameter placeholders when completing a function
    },
    //"go.languageServerFlags": ["-logfile", "D:/gopls.txt","-rpc.trace"],//gopls日志trace跟踪与文件记录
    "files.eol": "\n"
}

3. 建立工作空间（WorkSpace）
   将项目根目录作为工作空间添加到VSCode（Add workspace folder）。

4 Go Tools

4.1 提供的语法特性

智能感知

• 自动补全(gocode)
• 方法签名帮助(gogetdoc 或者godef+go doc)
• 光标置于代码上时，快速的代码信息提示(gogetdoc 或者 godef+go doc)

代码导航

• 跳转或查看符号定义 ( gogetdoc 或 godef+go doc)
• 查找接口实现的符号引用 ( guru)
• 跳转到符号所在文件位置，或者在当前文件中显示符号所在文件符号的大概信息 (go-outline)
• 在workspace中查找指定符号 (using go-symbols)
• 绑定Go程序文件和其对应的测试文件

代码编辑

• 快速编码的 代码片段
• Format code on file save as well as format manually (using goreturns or goimports which also remove unused imports or gofmt). To disable the format on save feature, add "[go]": {"editor.formatOnSave": false} to your settings.
• Symbol Rename (using gorename. Note: For Undo after rename to work in Windows you need to have diff tool in your path)
• Add Imports to current file (using gopkgs)
• Add/Remove Tags on struct fields (using gomodifytags)
• Generate method stubs for interfaces (using impl)
• Fill struct literals with default values (using fillstruct)

Diagnostics

• Build-on-save to compile code and show build errors. (using go build and go test)
• Vet-on-save to run go vet and show errors as warnings
• Lint-on-save to show linting errors as warnings (using golint, gometalinter, staticcheck, golangci-lint or revive)
• Semantic/Syntactic error reporting as you type (using gotype-live)

Testing

• Run Tests under the cursor, in current file, in current package, in the whole workspace using either commands or codelens
• Run Benchmarks under the cursor using either commands or codelens
• Show code coverage either on demand or after running tests in the package.
• Generate unit tests skeleton (using gotests)

Debugging

• Debug your code, binaries or tests (using delve)

Others

• Install/Update all dependent Go tools
• Upload to the Go Playground (using goplay)

5 gopls

6 go Extensions和gopls 配置

• 1 再VSCode中更新go Extensions和gopls

Command + Shift + P
Input go install
Select -> Go: Install/Update Tools
Select All -> OK 

7 要注意的地方

1. 如果想使用的扩展工具有单独的path，可以使用go.toolsGopath设置