provide Environment construction option to use stored configuration settings - close #78

build_tests/configure/check_cfg_use.rb

@@ -0,0 +1,15 @@
+configure do
+  check_cfg package: "mypackage", use: "myp"
+end
+
+build do
+  Environment.new(echo: :command) do |env|
+    env.Copy("myconfigtest1.c", "simple.c")
+    env.Program("myconfigtest1.exe", "myconfigtest1.c")
+  end
+
+  Environment.new(echo: :command, use: "myp") do |env|
+    env.Copy("myconfigtest2.c", "simple.c")
+    env.Program("myconfigtest2.exe", "myconfigtest2.c")
+  end
+end

build_tests/configure/check_lib_use.rb

@@ -0,0 +1,15 @@
+configure do
+  check_lib "m", use: :m
+end
+
+build do
+  Environment.new(echo: :command) do |env|
+    env.Copy("test1.c", "simple.c")
+    env.Program("test2.exe", "test1.c")
+  end
+
+  Environment.new(echo: :command, use: %w[m]) do |env|
+    env.Copy("test2.c", "simple.c")
+    env.Program("test2.exe", "test2.c")
+  end
+end

lib/rscons/basic_environment.rb

@@ -3,8 +3,14 @@ module Rscons
   class BasicEnvironment
 
     # Create a BasicEnvironment object.
-    def initialize
+    #
+    # @api private
+    #
+    # @param options [Hash]
+    #   Construction options.
+    def initialize(options = {})
       @varset = VarSet.new(Rscons.application.default_varset)
+      load_configuration_data!(options)
     end
 
     # Get a construction variable's value.
@@ -185,15 +191,24 @@ module Rscons
       end
     end
 
-    # Load construction variables saved from the configure operation.
-    def load_configuration_data!
+    # Load all construction variables saved from the configure operation.
+    def load_configuration_data!(options)
       if vars = Cache.instance.configuration_data["vars"]
         if default_vars = vars["_default_"]
           apply_configuration_data!(default_vars)
         end
+        if options[:use]
+          Array(options[:use]).each do |use|
+            if use_vars = vars[use]
+              apply_configuration_data!(use_vars)
+            end
+          end
+        end
       end
     end
 
+    # Load a specific set of construction variables saved from the configure
+    # operation.
     def apply_configuration_data!(vars)
       if merge_vars = vars["merge"]
         append(merge_vars)

lib/rscons/configure_op.rb

@@ -360,7 +360,12 @@ module Rscons
     # @return [Hash]
     #   Configuration Hash for storing vars.
     def store_common(options)
-      usename = options[:use] || "_default_"
+      usename =
+        if options[:use]
+          options[:use].to_s
+        else
+          "_default_"
+        end
       cache = Cache.instance
       cache.configuration_data["vars"] ||= {}
       cache.configuration_data["vars"][usename] ||= {}

lib/rscons/environment.rb

@@ -64,7 +64,7 @@ module Rscons
     # If a block is given, the Environment object is yielded to the block and
     # when the block returns, the {#process} method is automatically called.
     def initialize(options = {})
-      super()
+      super(options)
       @id = self.class.get_id
       self.class.register(self)
       @threaded_commands = Set.new
@@ -83,7 +83,6 @@ module Rscons
       end
       @echo = options[:echo] || :short
       @build_root = "#{Cache.instance.configuration_data["build_dir"]}/e.#{@id}"
-      load_configuration_data!
 
       if block_given?
         yield self

spec/build_tests_spec.rb

@@ -1782,6 +1782,16 @@ EOF
         expect(result.stdout).to match /Checking for library 'm'... found/
         expect(result.stdout).to match /gcc.*-lm/
       end
+
+      it "does not link against the checked library by default if :use is specified" do
+        test_dir "configure"
+        result = run_rscons(rsconscript: "check_lib_use.rb", op: "build")
+        expect(result.stderr).to eq ""
+        expect(result.status).to eq 0
+        expect(result.stdout).to match /Checking for library 'm'... found/
+        expect(result.stdout).to_not match /gcc.*test1.*-lm/
+        expect(result.stdout).to match /gcc.*test2.*-lm/
+      end
     end
 
     context "check_program" do
@@ -1832,6 +1842,20 @@ EOF
           expect(result.status).to_not eq 0
           expect(result.stdout).to match /Checking 'my-config'\.\.\. not found/
         end
+
+        it "does not use the flags found by default if :use is specified" do
+          test_dir "configure"
+          create_exe "pkg-config", "echo '-DMYPACKAGE'"
+          result = run_rscons(rsconscript: "check_cfg_use.rb", op: "configure")
+          expect(result.stderr).to eq ""
+          expect(result.status).to eq 0
+          expect(result.stdout).to match /Checking for package 'mypackage'\.\.\. found/
+          result = run_rscons(rsconscript: "check_cfg_use.rb", op: "build")
+          expect(result.stderr).to eq ""
+          expect(result.status).to eq 0
+          expect(result.stdout).to_not match /gcc.*-o.*myconfigtest1.*-DMYPACKAGE/
+          expect(result.stdout).to match /gcc.*-o.*myconfigtest2.*-DMYPACKAGE/
+        end
       end
 
       context "when passed a program" do