CodeBlocks generator is deprecated

[christian-rauch]

The build step shows the warning:

CMake Deprecation Warning:
  Support for "Extra Generators" like

    CodeBlocks

  is deprecated and will be removed from a future version of CMake.  IDEs may
  use the cmake-file-api(7) to view CMake-generated project build trees.

And the CMake documentation for CodeBlocks mentions that this will be removed in future:

Deprecated since version 3.27: Support for Extra Generators is deprecated and will be removed from a future version of CMake. IDEs may use the cmake-file-api(7) to view CMake-generated project build trees.

The build tools set the CodeBlocks - Unix Makefiles generator explicitly in many places via --cmake-args -G \"CodeBlocks - Unix Makefiles\" and there is a dedicated function ROSUtils::parseCodeBlocksFile to parse them.

@Levi-Armstrong What is the reason for using one of the CodeBlocks generators? What information is extracted from the cbp? Is this only to create the content for ROSUtils::PackageBuildInfoMap? What is the reason that we cannot use the default generator here?

[Levi-Armstrong]

This is what the old cmake plugin used for building the code model so did the same for the roster plugin, but not sure how that is currently being done in the plugin now.

[christian-rauch]

I am trying to understand what ROSUtils::parseCodeBlocksFile does, as it seems that this is the only part that makes use of the generated .cbp files. As far as I can tell, it parses the .cbp files per package / CMake project and adds targets to ROSUtils::PackageBuildInfo / PackageTargetInfoList:

ros_qtc_plugin/src/project_manager/ros_utils.cpp

Line 740 in 614c46a

buildInfo.targets.append(targetInfo);

This in the end, seems to be used only in the ROSProject::buildCppCodeModel:

ros_qtc_plugin/src/project_manager/ros_project.cpp

Lines 495 to 532 in 614c46a

	for (const ROSUtils::PackageTargetInfoPtr& targetInfo : buildInfo.targets)
	{
	ProjectExplorer::RawProjectPart rpp;
	const QString defineArg
	= Utils::transform(targetInfo->defines, [](const QString &s) -> QString {
	QString result = QString::fromLatin1("#define ") + s;
	int assignIndex = result.indexOf('=');
	if (assignIndex != -1)
	result[assignIndex] = ' ';
	return result;
	}).join('\n');
	rpp.setProjectFileLocation(projectFilePath);
	rpp.setBuildSystemTarget(buildInfo.parent.name + '|' + targetInfo->name + '|' + projectFilePath.toString());
	rpp.setDisplayName(buildInfo.parent.name + '|' + targetInfo->name);
	rpp.setQtVersion(activeQtVersion);
	rpp.setMacros(ProjectExplorer::Macro::toMacros(defineArg.toUtf8()));
	QSet<QString> toolChainIncludes;
	const HeaderPaths header_paths = \
	cxxToolChain->createBuiltInHeaderPathsRunner(env)\
	(targetInfo->flags, sysRoot, QString());
	for (const HeaderPath &hp : header_paths) {
	toolChainIncludes.insert(hp.path);
	}
	for (const QString &i : targetInfo->includes) {
	if (!toolChainIncludes.contains(i) && !package_includes.contains(i)) {
	packageHeaderPaths.append(ProjectExplorer::HeaderPath(i, ProjectExplorer::HeaderPathType::System));
	package_includes.append(i);
	}
	}
	rpp.setFlagsForCxx({cxxToolChain, targetInfo->flags, sysRoot});
	rpp.setFiles(targetInfo->source_files);
	rpp.setHeaderPaths(packageHeaderPaths);
	rpps.append(rpp);
	}

to populate ProjectExplorer::RawProjectPart.

I initially assumed that this is for showing the source and header files in the "Projects View" of the workspace. But those are already shown before compiling and removing -G \"CodeBlocks - Unix Makefiles\" and ROSUtils::parseCodeBlocksFile also compile the workspace successfully.

@Levi-Armstrong For which feature in Qt Creator are these targets from the .cbp files used? Or in other words, if we would remove the generation and parsing of the .cbp files, what would break?

[Levi-Armstrong]

This builds the code model which is used for code completion, refactoring, code following, etc.

[Levi-Armstrong]

This is how the old cmake project code worked so you might be able to leverage what they do now.