前提
- 安装dlv
go install github.com/go-delve/delve/cmd/dlv@latest
命令行debug的方式
- 切换至对应目录
root@helious:/usr/lib/go-1.18/src/io# go test -c -gcflags='all=-N -l' -o ./__debug_bin - dlv debug
dlv exec ./__debug_bin b funcName - 直接使用dlv
dlv test path_to_file -- test.v --test.run TestFuncName dlv test io/pipe_test.go -- -test.v --test.run ^TestPipeWriteClose$
使用VScode进行debug
前提：
- 安装vscode go extension
-
设置
launch.json定义debug行为的启动方式{ // Use IntelliSense to learn about possible attributes. // Hover to view descriptions of existing attributes. // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387 "version": "0.2.0", "configurations": [ { "name": "Launch golang debug function", "type": "go", "request": "launch", "mode": "auto", "program": "{workspaceFolder}/{relativeFileDirname}", "console": "internalConsole", "args": [ "--", "-test.v", "-test.run", "^FunctionName$", ] } ] }
注意，如果你和我一样在调试时发现无论如何设置断点，vscode总是断点失败，像是未生效一般。
首先，你需要确保你的程序没有bug，即按照命令行debug的方式是可以正常运行的，那么这是你需要打开vscode的debug输出
修改launch.json，增加如下内容
"configurations": [
{
....
"console": "internalConsole",
"logOutput": "dap",
"showLog": true,
"trace": "verbose",
}
]
这里我想debug的文件是/usr/lib/go-1.18/src/io/pipe_test.go
vscode输出如下
2023-05-28T12:14:25+08:00 debug layer=dap [-> to client]
{"seq":0,"type":"response","request_seq":4,"success":true,"command":"setBreakpoints","body":{"breakpoints":
[{"verified":false,"message":"could not find file /usr/lib/go-1.18/src/io/pipe_test.go","source":{}},
{"verified":false,"message":"could not find file /usr/lib/go-1.18/src/io/pipe_test.go","source":{}},
{"verified":false,"message":"could not find file /usr/lib/go-1.18/src/io/pipe_test.go","source":{}},
{"verified":false,"message":"could not find file /usr/lib/go-1.18/src/io/pipe_test.go","source":{}},
{"verified":false,"message":"could not find file /usr/lib/go-1.18/src/io/pipe_test.go","source":{}},
{"verified":false,"message":"could not find file /usr/lib/go-1.18/src/io/pipe_test.go","source":{}},
{"verified":false,"message":"could not find file /usr/lib/go-1.18/src/io/pipe_test.go","source":{}}]}}
有些奇怪，看起来像是vscode找不到需要debug的文件，所以导致无法断点。一番搜索后，找到了这个VSCode Breakpoint not hitting/stopping when run in debugger mode – Golang · Issue #2417
这里提到导致问题的原因可能是/usr/lib/go-1.18/src/io/pipe_test.go 是一个软连接目录，所以导致vscode无法找到对应的文件，也就无法下断点。
那我们确认下
root@helious:/usr/lib/go-1.18# pwd
/usr/lib/go-1.18
root@helious:/usr/lib/go-1.18# ls -l
total 12
-rw-r--r-- 1 root root 8 Jul 30 2022 VERSION
lrwxrwxrwx 1 root root 23 Apr 13 2022 api -> ../../share/go-1.18/api
drwxr-xr-x 2 root root 4096 Nov 13 2022 bin
lrwxrwxrwx 1 root root 24 Apr 13 2022 misc -> ../../share/go-1.18/misc
drwxr-xr-x 4 root root 4096 May 4 2022 pkg
lrwxrwxrwx 1 root root 23 Apr 13 2022 src -> ../../share/go-1.18/src
lrwxrwxrwx 1 root root 24 Apr 13 2022 test -> ../../share/go-1.18/test
root@helious:/usr/lib/go-1.18# realpath ./src
/usr/share/go-1.18/src
root@helious:/usr/lib/go-1.18#
这里我们可以看到，golang的默认安装源码路径实际是在/usr/share/go-1.18/src路径下
那对应的解决办法是在launch.json中添加
"substitutePath": [
{
"from": "/usr/lib/go-1.18/src",
"to": "/usr/share/go-1.18/src"
}
]
结论
- 如果你发现无论通过Visual Code 界面怎样断点都不生效，但是通过命令行方式可以正常Debug，那么可能是因为你当前的源码目录是一个相对路径，改为绝对路径即可
- 有任何问题打开Debug日志可以帮助分析