Print a @warn message if the user provides an unsupported kwarg

Author: DilumAluthge

src/slurmmanager.jl

@@ -122,8 +122,60 @@ function _new_environment_additions(params_env::Dict{String, String})
   return env2
 end
 
+function warn_if_unexpected_params(params::Dict)
+    params_that_we_support = [:dir, :exename, :exeflags]
+    upstreams_defaults = Distributed.default_addprocs_params()
+    for (k, v) in pairs(params)
+        if k == :env
+            # We special-case `:env`, because our support status depends on the Julia version
+            if v == []
+                # Either the user didn't provide the `:env` kwarg,
+                # or the user provided `env=[]`.
+                #
+                # Either way, in this case, we don't print a log message.
+                # @debug "k == :env and v == []" k v
+            else
+                # In this case, the user has provided the `:env` kwarg, and it is nonempty.
+                if Base.VERSION < v"1.6.0"
+                   @warn "The user provided the `env` kwarg, but SlurmClusterManager.jl's support for the `env` kwarg requires Julia 1.6 or later" Base.VERSION
+                else
+                   # Here, the Julia version is >= 1.6, so we do support `:env`,
+                   # and there is no problem.
+                end
+            end
+        elseif k in params_that_we_support
+            # We support this param, so no problem.
+        else
+            # We don't support this param.
+
+            # So let's see if this is something that Distributed.jl would provide by default.
+            if haskey(upstreams_defaults, k)
+                # This is a param that Distributed.jl would provide by default.
+                # So now the question is: is this the default value provided by Distributed.jl,
+                # or did the user override the value?
+                this_is_upstreams_default_value = v == upstreams_defaults[k]
+                if this_is_upstreams_default_value
+                    # So now the question is: is this the default value provided by Distributed.jl,
+                    # This IS the default value provided by Distributed.jl, so we won't print a log message.
+                    # @debug "" k v this_is_upstreams_default_value
+                else
+                   # This is NOT the default value provided by Distributed.jl.
+                   # So the user must have overriden the value.
+                   @warn "SlurmClusterManager.jl does not support this kwarg: $(k)" kwarg=k value=v
+                end
+            else
+                # This is not a param that Distributed.jl provides by default.
+                @warn "SlurmClusterManager.jl does not support this custom kwarg: $(k)" kwarg=k value=v
+            end
+        end
+    end
+    return nothing
+end
+
 function Distributed.launch(manager::SlurmManager, params::Dict, instances_arr::Array, c::Condition)
     try
+        warn_if_unexpected_params(params)
+
         exehome = params[:dir]
         exename = params[:exename]
         exeflags = params[:exeflags]