Phoityne VSCode

Phoityne is a Haskell GHCi debug adapter for Visual Studio Code.

Information

• [2018/08/01] phoityne-vscode released.
  • Marketplace phoityne-vscode-0.0.19
  • hackage phoityne-vscode-0.0.26.0
    Need update from hackage !!.
• Release Summary
  • [UPDATE] supported haskell-dap-0.0.7.0

(This sample project is available from here.)

Important

• LIMITATION: Source file extension must be ".hs"
• LIMITATION: Can not use STDIN handle while debugging.
• When you start debugging for the first time, .vscode/tasks.json will be created automatically. Then you can use F6, F7, F8 shortcut key.
  • F5 : start debug
  • F6 : show command menu (for stack watch)
  • Shift + F6 : stop stack watch
  • F7 : stack clean & build
  • F8 : stack test
  • F9 : put bp on current line
  • Shift + F9 : put bp on current column
• While debugging, you can use F5, F9, F10, F11 shortcut key.
  • F5 : jump to next bp
  • F9 : put bp on the line
  • Shift + F9 : put bp on the column
  • F10 : step next
  • F11 : step into

Features

Run to Cursor

Bindings & Watch

The variable added to watch will be forced.

Stack trace

Break condition

Hit count break condition

Supports these operators.

• ==
• /=
• <, >
• <=, >=
• mod, %
• just digit is same with '>='

Break on Exception

Repl & Completions

and more

Better inspection. This is an experimental enhancement.
There are limitations and additional installation.
Here are the details.

Capabilites

• supportsConfigurationDoneRequest : yes
• supportsFunctionBreakpoints : yes
• supportsConditionalBreakpoints : yes
• supportsHitConditionalBreakpoints : yes
• supportsEvaluateForHovers : yes
• exceptionBreakpointFilters : yes
• supportsStepBack : no
• supportsSetVariable : no
• supportsRestartFrame : no
• supportsGotoTargetsRequest : no
• supportsStepInTargetsRequest : no
• supportsCompletionsRequest : yes
• supportsModulesRequest : no
• additionalModuleColumns : no
• supportedChecksumAlgorithms : no
• supportsRestartRequest : no
• supportsExceptionOptions : no
• supportsValueFormattingOptions : no
• supportsExceptionInfoRequest : no
• supportTerminateDebuggee : no
• supportsDelayedStackTraceLoading : no
• supportsLogPoints : yes (by haskell-dap)

Install

Run stack install

% stack install phoityne-vscode
  . . . . .
%

Add 'phoityne-vscode.exe' to PATH environment.

Windows)

% where $path:phoityne-vscode.exe
C:\Users\[user name]\AppData\Roaming\local\bin\phoityne-vscode.exe

% phoityne-vscode --version
phoityne-vscode-x.x.x.x
%
% code

linux)

$ which phoityne-vscode
~/.local/bin/phoityne-vscode
$
$ phoityne-vscode --version
phoityne-vscode-x.x.x.x
$
$ code

Install vscode extensions

1. run VSCode and open stack project Folder from file menu.
2. open Extensions from side menu of VSCode.
3. search "haskell"
4. select "Haskell GHCi debug adapter Phoityne"

Configuration

.vscode/launch.json

changing ghci initial prompt

If you change ghci prompt in .ghci file, or ghci prompt is changed from "Prelude>" by applying NoImplicitPrelude extension, set the initial prompt variable to same prompt string.

% diff .vscode/launch.json.old .vscode/launch.json
19c19
<             "ghciInitialPrompt": "Prelude> "      // default value.
---
>             "ghciInitialPrompt": "> "             // e.g.
%

Make sure needs of the last space, and don't forget adding it.

setting the startup hs file

Set the startup variable to the path of .hs file in which main function is defined.

% diff .vscode/launch.json.old .vscode/launch.json
10c10
<             "startup": "${workspaceRoot}/test/Spec.hs",    // default value.
---
>             "startup": "${workspaceRoot}/app/run.hs",     // e.g.
%

setting the startup function

If you want to run the specific function instead of main function, set the startupFunc variable.
For example, when specifying the following startDebug function,

startDebug :: String -> IO ()
startDebug name = do
  putStrLn "hello"
  putStrLn name 

set the valiavles in the launch.json file.

% diff .vscode/launch.json.old .vscode/launch.json
11c12
<             "startupFunc": "",    // default value.
<             "startupArgs": "",    // default value.
---
>             "startupFunc": "startDebug",       // e.g.
>             "startupArgs": "\"phoityne\"",     // e.g.
%

changing log level

For debuging phoityen itself, change the log level to DEBUG.
Adding Issue with the debug log.

% diff .vscode/launch.json.old .vscode/launch.json
12c12
<             "logLevel": "WARNING",               // default value.
---
>             "logLevel": "DEBUG",                 // e.g.
%

.vscode/tasks.json