By default, propagate Base.active_project(), Base.LOAD_PATH, and Base.DEPOT_PATH to the workers (but allow the user to override that behavior by specifying JULIA_{PROJECT,LOAD_PATH,DEPOT_PATH} in params[:env]

Co-authored-by: jbphyswx <jbenjami@caltech.edu>

Author: DilumAluthge

src/slurmmanager.jl

@@ -47,7 +47,7 @@ end
   # In Julia 1.9 and later, the no-argument method `Distributed.default_addprocs_params()`
   # includes :env, so we don't need to do anything.
   # See also: https://github.com/JuliaLang/julia/blob/v1.9.0/stdlib/Distributed/src/cluster.jl#L526-L541
-  
+
   Distributed.default_addprocs_params(::SlurmManager) = Distributed.default_addprocs_params()
 elseif v"1.6.0" <= Base.VERSION < v"1.9.0"
   # In Julia 1.6 through 1.8, the no-argument method `Distributed.default_addprocs_params()`
@@ -72,6 +72,73 @@ elseif Base.VERSION < v"1.6.0"
   # so we will just choose to not support `params[:env]` on Julia 1.5 and earlier.
 end
 
+function _new_environment_additions(params_env::Dict{String, String})
+  env2 = Dict{String, String}()
+  user_did_specify = Dict{String, Bool}
+  user_did_specify_JULIA_PROJECT = false
+  user_did_specify_JULIA_LOAD_PATH = false
+  user_did_specify_JULIA_DEPOT_PATH = false
+
+  for (name, value) in pairs(params_env)
+    # For each key-value mapping in `params[:env]`, we respect that mapping and we pass it
+    # to the workers.
+    env2[name] = value
+
+    # If the user did specify `JULIA_{PROJECT,LOAD_PATH,DEPOT_PATH}` in `params[:env]`, then
+    # we respect that value, and we pass it to the workers.
+    if name == "JULIA_PROJECT"
+      user_did_specify_JULIA_PROJECT = true
+      @debug "The user did specify a value for JULIA_PROJECT in the `env` kwarg to `addprocs()`; that value will be passed to the workers" env2[JULIA_PROJECT]
+    end
+    if name == "JULIA_LOAD_PATH"
+      user_did_specify_JULIA_LOAD_PATH = true
+      @debug "The user did specify a value for JULIA_LOAD_PATH in the `env` kwarg to `addprocs()`; that value will be passed to the workers" env2[JULIA_LOAD_PATH]
+    end
+    if name == "JULIA_DEPOT_PATH"
+      user_did_specify_JULIA_DEPOT_PATH = true
+      @debug "The user did specify a value for JULIA_DEPOT_PATH in the `env` kwarg to `addprocs()`; that value will be passed to the workers" env2[JULIA_DEPOT_PATH]
+    end
+  end
+
+  directory_separator = Sys.iswindows ? ';' : ':'
+
+  # If the user did not specify `JULIA_PROJECT` in `params[:env]`, then we pass
+  # JULIA_PROJECT=Base.active_project() to the workers.
+  #
+  # This use case is commonly hit when the user does NOT set the `JULIA_PROJECT` environment
+  # variable but DOES start Julia with either `julia --project` or `julia --project=something`.
+  #
+  # https://github.com/kleinhenz/SlurmClusterManager.jl/issues/16
+  if !user_did_specify_JULIA_PROJECT
+    # Important note: We use  Base.active_project() here.
+    # We do NOT use Base.ACTIVE_PROJECT[], because it is not part of Julia's public API.
+    env2["JULIA_PROJECT"] = Base.active_project()
+    @debug "Passing JULIA_PROJECT=Base.active_project() to the workers" env2["JULIA_PROJECT"]
+  end
+
+  # If the user did not specify `JULIA_LOAD_PATH` in `params[:env]`, then we pass
+  # JULIA_LOAD_PATH=Base.LOAD_PATH to the workers.
+  #
+  # This is a bit of an edge case, and I doubt that most users will need it.
+  # But upstream Distributed.jl does it, so we might as well do it too.
+  if !user_did_specify_JULIA_LOAD_PATH
+    env2["JULIA_LOAD_PATH"] = join(Base.LOAD_PATH, directory_separator)
+    @debug "Passing JULIA_LOAD_PATH=Base.LOAD_PATH to the workers" env2["JULIA_LOAD_PATH"]
+  end
+
+  # If the user did not specify `JULIA_DEPOT_PATH` in `params[:env]`, then we pass
+  # JULIA_DEPOT_PATH=Base.DEPOT_PATH to the workers.
+  #
+  # This is a bit of an edge case, and I doubt that most users will need it.
+  # But upstream Distributed.jl does it, so we might as well do it too.
+  if !user_did_specify_JULIA_DEPOT_PATH
+    env2["JULIA_DEPOT_PATH"] = join(Base.DEPOT_PATH, directory_separator)
+    @debug "Passing JULIA_DEPOT_PATH=Base.DEPOT_PATH to the workers" env2["JULIA_DEPOT_PATH"]
+  end
+
+  return env2
+end
+
 function launch(manager::SlurmManager, params::Dict, instances_arr::Array, c::Condition)
     try
         exehome = params[:dir]