From df120af9539378b9805c9ef4c4b16c0b13d483ec Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop@gmail.com>
Date: Sun, 30 Jan 2022 15:00:59 -0500
Subject: [PATCH] Add env.expand() shortcut method to expand paths and
 construction variables - close #150

---
 doc/user_guide.md         |  2 +-
 lib/rscons/builder.rb     |  2 +-
 lib/rscons/environment.rb | 26 +++++++++++++++++++-------
 3 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/doc/user_guide.md b/doc/user_guide.md
index b83d270..3c72bad 100644
--- a/doc/user_guide.md
+++ b/doc/user_guide.md
@@ -224,7 +224,7 @@ task "build" do
 end
 
 task "flash", deps: "build" do
-  sh "nrfjprog", "-f", "NRF52", "--program", env.expand_path("^^/proj.elf")
+  sh "nrfjprog", "-f", "NRF52", "--program", env.expand("^^/proj.elf")
 end
 ```
 
diff --git a/lib/rscons/builder.rb b/lib/rscons/builder.rb
index abdbf22..fa844dd 100644
--- a/lib/rscons/builder.rb
+++ b/lib/rscons/builder.rb
@@ -103,7 +103,7 @@ module Rscons
     # @return [void]
     def produces(*side_effects)
       side_effects.each do |side_effect|
-        side_effect_expanded = @env.expand_path(@env.expand_varref(side_effect))
+        side_effect_expanded = @env.expand(side_effect)
         @env.register_side_effect(side_effect_expanded)
         @side_effects << side_effect_expanded
       end
diff --git a/lib/rscons/environment.rb b/lib/rscons/environment.rb
index aba5988..ab4bb46 100644
--- a/lib/rscons/environment.rb
+++ b/lib/rscons/environment.rb
@@ -337,10 +337,10 @@ module Rscons
         unless vars.is_a?(Hash) or vars.is_a?(VarSet)
           raise "Unexpected construction variable set: #{vars.inspect}"
         end
-        target = expand_path(expand_varref(target))
+        target = expand(target)
         sources = Array(sources).map do |source|
           source = source.target if source.is_a?(Builder)
-          expand_path(expand_varref(source))
+          expand(source)
         end.flatten
         builder = @builders[method.to_s].new(
           target: target,
@@ -369,12 +369,12 @@ module Rscons
       if target.is_a?(Builder)
         target = target.target
       end
-      target = expand_path(expand_varref(target.to_s))
+      target = expand(target.to_s)
       user_deps = user_deps.map do |ud|
         if ud.is_a?(Builder)
           ud = ud.target
         end
-        expand_path(expand_varref(ud))
+        expand(ud)
       end
       @user_deps[target] ||= []
       @user_deps[target] = (@user_deps[target] + user_deps).uniq
@@ -408,13 +408,13 @@ module Rscons
       targets = Array(targets)
       prerequisites = Array(prerequisites)
       targets.each do |target|
-        target = expand_path(expand_varref(target))
+        target = expand(target)
         @registered_build_dependencies[target] ||= Set.new
         prerequisites.each do |prerequisite|
           if prerequisite.is_a?(Builder)
             prerequisite = prerequisite.target
           end
-          prerequisite = expand_path(expand_varref(prerequisite))
+          prerequisite = expand(prerequisite)
           @registered_build_dependencies[target] << prerequisite
         end
       end
@@ -430,7 +430,7 @@ module Rscons
     #
     # @return [void]
     def produces(target, *side_effects)
-      target = expand_path(expand_varref(target))
+      target = expand(target)
       @builder_sets.reverse.each do |builder_set|
         if builders = builder_set[target]
           builders.last.produces(*side_effects)
@@ -514,6 +514,18 @@ module Rscons
       end
     end
 
+    # Expand construction variable references and paths.
+    #
+    # @param expr [String]
+    #   Expression to expand. Can contain construction variable references and
+    #   a path.
+    #
+    # @return [String, Array<String>]
+    #   Expanded value.
+    def expand(expr)
+      expand_path(expand_varref(expr))
+    end
+
     # Print the builder run message, depending on the Environment's echo mode.
     #
     # @param builder [Builder]