DAP Debugger Setup

DAP Debugger Setup

VimCode has built-in Debug Adapter Protocol (DAP) support with a VSCode-like debugging UI.

Quick start

1. Install a debug adapter for your language:

   :DapInstall rust       " or python, go, javascript, java, csharp

2. Set a breakpoint — press F9 on the line you want to break at

3. Start debugging — press F5 (or click the play button in the debug sidebar)

4. A launch.json file is generated automatically in .vimcode/launch.json on first run

Supported adapters

Language	Adapter	Registry name	Install command
Rust / C / C++	codelldb	codelldb	:DapInstall rust or :DapInstall cpp
Python	debugpy	debugpy	:DapInstall python
Go	delve	delve	:DapInstall go
JavaScript / TypeScript	js-debug	js-debug	:DapInstall javascript
Java	java-debug	java-debug	:DapInstall java
C#	netcoredbg	netcoredbg	:DapInstall csharp

Debug sidebar

Open the debug sidebar by clicking the bug icon in the activity bar. It has four interactive sections:

Variables

• Shows local/scope variables with their current values
• Enter expands/collapses nested children (recursive)
• Additional scope groups (Statics, Registers, etc.) appear as expandable headers
• C# private fields are automatically grouped under Non-Public Members

Watch

• User-defined watch expressions
• Add with :DapWatch <expr>
• x or d removes the selected expression

Call Stack

• Shows all stack frames
• Enter selects a frame and navigates to its source
• Active frame marked with ▶

Breakpoints

• Lists all set breakpoints with conditions
• Enter jumps to the breakpoint's location
• x or d removes the selected breakpoint

Navigation

Key	Action
j / k	Navigate items
Tab	Switch between sections
Enter	Expand/select/jump
x / d	Delete item (watch/breakpoint)
q / Escape	Unfocus sidebar
Mouse click	Select item or section header

Breakpoints

Basic breakpoints

• F9 — toggle a breakpoint on the current line
• Breakpoints are shown in the gutter: ● (normal), ◆ (conditional)

Conditional breakpoints

:DapCondition x > 10           " Stop only when expression is truthy
:DapCondition                  " Clear condition on current line's BP
:DapHitCondition >= 5          " Stop after N hits
:DapHitCondition               " Clear hit condition
:DapLogMessage Processing item " Print message instead of stopping (logpoint)
:DapLogMessage                 " Clear logpoint

Place cursor on a line with a breakpoint, then run the command.

Debugging keys

Key	Action
F5	Start debugging / continue
Shift+F5	Stop debugging
F6	Pause
F9	Toggle breakpoint on current line
F10	Step over
F11	Step into
Shift+F11	Step out

Debug commands

Command	Action
:DapInstall <lang>	Install debug adapter for language
:DapInfo	Show detected DAP adapters
:DapEval <expr>	Evaluate expression in current frame
:DapWatch <expr>	Add watch expression
:DapCondition [expr]	Set/clear condition on breakpoint at cursor
:DapHitCondition [count]	Set/clear hit-count condition
:DapLogMessage [msg]	Set/clear logpoint
:DapBottomPanel terminal|output	Switch bottom panel tab

launch.json

VimCode auto-generates a launch.json on first debug run:

.vimcode/launch.json

If you have an existing .vscode/launch.json, it is auto-migrated to .vimcode/ on first use.

Format

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Debug",
            "type": "codelldb",
            "request": "launch",
            "program": "${workspaceFolder}/target/debug/myapp",
            "args": [],
            "cwd": "${workspaceFolder}",
            "preLaunchTask": "build"
        }
    ]
}

Variable substitution

Variable	Value
${workspaceFolder}	Project root directory
${workspaceFolderBasename}	Project root directory name

Multiple configurations

Add multiple entries to the configurations array. When starting debugging, VimCode uses the selected configuration from the debug sidebar dropdown.

tasks.json + preLaunchTask

If a launch configuration has "preLaunchTask": "build", VimCode loads .vimcode/tasks.json (auto-migrated from .vscode/tasks.json) and runs the matching task before starting the debug adapter.

{
    "version": "2.0.0",
    "tasks": [
        {
            "label": "build",
            "type": "shell",
            "command": "cargo build"
        }
    ]
}

Task output appears in the Debug Output panel. If the task fails, the debug session is aborted.

Gutter indicators

Symbol	Meaning
●	Breakpoint set
◆	Conditional breakpoint
▶	Current execution line (stopped)
◉	Breakpoint + current line

Bottom panel

When debugging, the bottom panel has two tabs:

• Terminal — integrated terminal
• Debug Output — adapter diagnostics and program output (scrollable, newest at bottom)

Language-specific notes

Rust

For Rust projects, VimCode auto-detects the debug binary using cargo metadata. The generated launch.json will point to the binary in target/debug/.

Make sure to build with debug info:

cargo build   # debug profile includes debug info by default

Python

debugpy requires Python 3.7+. Install:

pip install debugpy

Go

delve requires Go 1.16+. Install:

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

C#

netcoredbg requires .NET SDK. Install via your package manager or from the Samsung/netcoredbg releases.