Feature Request: Add Base.active_manifest

[oscardssmith]

This is analogous to Base.active_project and returns the path of the active manifest file. This function likely doesn't exist yet because people assume it can be spelled joinpath(Base.active_project(), "Manifest.toml") which will work ~90% of the time, but the manifest can be called JuliaManifest.toml or [email protected] or if the Project.toml is using the [workspace] section, can live in a completely separate directory and be named anything.

Pkg has this information at Pkg.Types.EnvCache().manifest_file but that is pretty deep internals to Pkg and thus probably shouldn't be relied on.

[KristofferC]

julia/base/loading.jl

Lines 821 to 857 in a046da5

	# find project file's corresponding manifest file
	function project_file_manifest_path(project_file::String)::Union{Nothing,String}
	@lock require_lock begin
	cache = LOADING_CACHE[]
	if cache !== nothing
	manifest_path = get(cache.project_file_manifest_path, project_file, missing)
	manifest_path === missing || return manifest_path
	end
	dir = abspath(dirname(project_file))
	d = parsed_toml(project_file)
	base_manifest = workspace_manifest(project_file)
	if base_manifest !== nothing
	return base_manifest
	end
	explicit_manifest = get(d, "manifest", nothing)::Union{String, Nothing}
	manifest_path = nothing
	if explicit_manifest !== nothing
	manifest_file = normpath(joinpath(dir, explicit_manifest))
	if isfile_casesensitive(manifest_file)
	manifest_path = manifest_file
	end
	end
	if manifest_path === nothing
	for mfst in manifest_names
	manifest_file = joinpath(dir, mfst)
	if isfile_casesensitive(manifest_file)
	manifest_path = manifest_file
	break
	end
	end
	end
	if cache !== nothing
	cache.project_file_manifest_path[project_file] = manifest_path
	end
	return manifest_path
	end
	end