Golang delve

delve is a go debugger.
It is more knowledgeable about the go runtime than golang gdb .
There are also editor integrations.

Documentation

github	https://github.com/go-delve/delve
command docs	https://github.com/go-delve/delve/blob/master/Documentation/cli/README.md
editor plugins	https://github.com/go-delve/delve/blob/master/Documentation/EditorIntegration.md

Locations

~/.config/dlv/config.yml

config options

Install

go install github.com/go-delve/delve/cmd/dlv@latest

Configuration

Persistent

# ~/.config/dlv/config.yml

max-string-len: 1000
max-array-values: 1000

Dynamic

Within a delve session, you can modify debugger config values.

config max-string-len 1000

Usage

Delve builds your executable automatically with flags required for it to debug your program.

Start Delve

# start debugger
dlv debug [example.com/x/foo/package] [-- [--your-params]]          # run program

dlv test                                  # run tests in PWD
dlv test ./internal/foo                   # run local tests in dir
dlv test example.com/x/foo/package        # run package on GOPATH
dlv test -- -test.run ^TestSanitizePath$  # run matching tests in PWD

# useful test params:
 -test.run  # regex test to match
 -test.v    # verbose (print tests as run)

Breakpoint

You can add breakpoints in src, or interactively

runtime.Breakpoint() // delve breakpoint

b main.main   # add breakpoint to 'main.go's 'main' method
b main.go:10  # add breakpoint to 'main.go's line 10

Session

Add your breakpoints, then continue to execute your program

c             # continue (start executing)

Inspect your program, learn

p yourVar  # print var
l          # print location
n          # next line (enters loop, not skip to end)
s          # step into line
<enter>    # repeat last command