call.rb in bolt-0.21.8

- old
+ new

@@ -4,10 +4,14 @@
 #
 # 1. A string corresponding to a function name.
 # 2. Any number of arguments to be passed to the called function.
 # 3. An optional lambda, if the function being called supports it.
 #
+# This function can also be used to resolve a `Deferred` given as
+# the only argument to the function (does not accept arguments nor
+# a block).
+#
 # @example Using the `call` function
 #
 # ```puppet
 # $a = 'notice'
 # call($a, 'message')
@@ -24,19 +28,52 @@
 # ```
 #
 # The `call` function can be used to call either Ruby functions or Puppet language
 # functions.
 #
+# When used with `Deferred` values, the deferred value can either describe
+# a function call, or a dig into a variable.
+#
+# @example Resolving a deferred function call
+#
+# ```puppet
+# $d = Deferred('join', [[1,2,3], ':']) # A future call to join that joins the arguments 1,2,3 with ':'
+# notice($d.call())
+# ```
+#
+# Would notice the string "1:2:3".
+#
+# @example Resolving a deferred variable value with optional dig into its structure
+#
+# ```puppet
+# $d = Deferred('$facts', ['processors', 'count'])
+# notice($d.call())
+# ```
+#
+# Would notice the value of `$facts['processors']['count']` at the time when the `call` is made.
+#
+# * Deferred values supported since Puppet 5.6.0
+#
 # @since 5.0.0
 #
 Puppet::Functions.create_function(:call, Puppet::Functions::InternalFunction) do
   dispatch :call_impl_block do
     scope_param
     param 'String', :function_name
     repeated_param 'Any', :arguments
     optional_block_param
   end
 
+  dispatch :call_deferred do
+    scope_param
+    param 'Deferred', :deferred
+  end
+
   def call_impl_block(scope, function_name, *args, &block)
     call_function_with_scope(scope, function_name, *args, &block)
   end
+
+  def call_deferred(scope, deferred)
+    Puppet::Pops::Evaluator::DeferredResolver.resolve(deferred, scope.compiler)
+  end
+
 end