Launching debugger in vscode for fpm projects

[bitli]

Hello,
I have successfully used vscode tasks and launcher to compile, launch and debug main programs from vscode and fpm. The difficulty was to find the location of the program to launch created in a generated directory as build/gfortran_2A42023B310FA28D/bin. The workaround was to create a work directory somewhere and use fpm install --prefix .../work instead of fpm build, so the binaries are at a predictable location. Then the launch.json can specify "program": "work/main" for the debugger and all works fine.
However when developing a library module I must test using programs in the test or example directories and I did not find a way to automatically copy the files to the work directory. May be a shell script could be called after the build task, but this is not very convenient especially in a multi-architecture project. I tried to use the command fpm test --runner gdb, but then the debug interface of vscode try to connect to fpm, not to the started gdb (or other strange things happens).
Any idea of what could be done ?
Ideally I would like to install the examples or test in a specific location, just like fpm install or build the project in a fixed directory or get the location of the build directory (this is less convenient).

[zoziha]

I am also using vscode (I think vscode and fpm work well together). When debugging, it is troublesome to find the correct executable program path. Maybe we can find a way.

I usually look up the executable program generation location patiently based on the running information of fpm (it seems that the location information contains a hash value), and then manually paste it into launch.json.

Digression (not important at this stage): I see that vscode has official plug-ins for languages such as julia and python. I wonder if the fortran community specifically wants to promote Fortran programming in vscode?

fpm test tester --runner ls

[bitli]

I used the same trick initially
But finally I use the workaround (works on Linux and for a specific executable):
I created a script as follow:

#!/bin/sh
# Find and isntall the example executables to ../release/bin
mkdir -p release/bin
rm -f release/bin/*
# Use the most recent output
GFORTRAN_DIR=`ls build -t | grep -m 1 gfortran_`
cp build/${GFORTRAN_DIR}/example/* release/bin
echo "Copied executables: " `ls release/bin`

in tasks.json, I use a new defautl build task that depends on the classic fpmbuild task:

       {
            "label": "prepare",
            "type": "shell",
            "command": "${workspaceFolder}/devenvs/vscode/install-examples.sh",
            "args": [
            ],
            "group": {
                "kind": "build",
                "isDefault": true
            },
            "dependsOn": ["fpmbuild"],

So the launch.json can have a fixed program to launch:

            ...
            "program": "${workspaceRoot}/release/bin/LoadWaveInfo",
            ...
            "preLaunchTask": "prepare",
            ...

This could be enhanced, for example to only copy the program named like the active windows if I have multiple examples and so on. But this is very environment, project and os specific, unfortunately.

[zoziha]

Hello, @bitli :

I am also a user of vs code. fpm runs in the built-in terminal of vs code and I write code using vs code. I think this experience is good, but as you said, configuring the launch.json file takes some time.
Based on interest, I quickly and simply wrote a small program vdb using Fortran to do this, and let it configure the launch.json file according to the arguments passed from fpm.
The effect is as follows:

The currently supported commands are:

fpm [options] <test_name> --runner vdb
fpm [options] <test_name> --runner vdb - ARGS
vdb clean # Remove and backup JSON::launch.json

Note: Because some file processing commands are used, such as mkdir and mv, I cannot guarantee that it will work under other systems, but it will work under windows 10 + msys2-gfortran + pwsh.

Link

• zoziha/vdb