Passing environment variable to "cmake" tasks

[TheophileBlard]

Brief Issue Summary

Is it possible to pass environment variable to cmake tasks ?

I'm currently using the pre-release version of the extension, and want to use cmake tasks to install the binaries to predefined directories using DESTDIR. For example, "shell" tasks provide the "env" keyword in "options", but for "cmake" tasks, only the "cwd" is available.

Thanks!

CMake Tools Diagnostics

No response

Debug Log

No response

Additional Information

CMakeTools version : 1.11.19
VSCode verson: 1.67.0
OS: Ubuntu 21.04 TLS

[elahehrashedi]

You can define an active configurePresets in CMakePresets.json, and set the CMAKE_INSTALL_PREFIX there.
Here is an example:

{
    "version": 2,
    "configurePresets": [
        {
            "name": "dev17-ninja-143",
            "displayName": "Ninja - v143,x64",
            "generator": "Ninja",
            "architecture": {
                "strategy": "external",
                "value": "x64"
            },
            "toolset": {
                "strategy": "external",
                "value": "host=x64,version=14.30"
            },
            "binaryDir": "${sourceDir}/out/build/${presetName}",
            "cacheVariables": {
                "CMAKE_BUILD_TYPE": "Debug",
                "CMAKE_INSTALL_PREFIX": "${sourceDir}/out/install/${presetName}"
            },
            "inherits": "base",
            "environment": {
                "PATH":  "$penv{PATH};D:\\ninja"
              }
        }
    ],

The Cmake Install Task will pick the settings from the active configurePresets and run the install. Will this approach solve your issue?
We can also look into adding more customizable features to cmake tasks in future.

[elahehrashedi]

One option that can be added to the configure or build task can be the name of the preset (instead of always picking the default). This feature is not available yet. We can look into adding it in future.
for example:

        {
            "type": "cmake",
            "label": "CMake: build",
            "command": "build",
            "targets": [
                "all"
            ],
            **"preset": "presetName",**
            "group": "build",
            "problemMatcher": [],
            "detail": "CMake template build task"
        }

[TheophileBlard]

Hi!

The DESTDIR variable is not interpreted at configure time but at install time, and it's not a CMake variable, but an environment variable that CMake uses to relocate the installation.
A typical use of this variable is:

DESTDIR=/package/stage cmake --install .

With the environment keyword of presets it seems that I can set DESTDIR to a custom directory. However, when I use the preset keyword in my tasks.json I get the following error: Property preset is not allowed.. Is this an unreleased feature ? I'm using v1.11.19 of CMake Tools.

Do you plan to add a way to set environment variables directly in CMake tasks ?

[elahehrashedi]

The DESTDIR variable is not interpreted at configure time but at install time, and it's not a CMake variable, but an environment variable that CMake uses to relocate the installation.

Thank you for your clarification.

However, when I use the preset keyword in my tasks.json I get the following error: Property preset is not allowed.
We can look into adding this feature in the future. Currently, the default preset will be picked.

Currently, as a workaround, you can add the environment variables in your default build preset.

I will use this issue to track adding environment variables to the cmake tasks.

[TheophileBlard]

Thank you !

[elahehrashedi]

There is an upcoming fix for this issue in PR #2636