move Rscons.absolute_path?() to Util

spec/rscons/util_spec.rb

@@ -1,6 +1,34 @@
 module Rscons
   describe Util do
 
+    describe ".absolute_path?" do
+      context "on Windows" do
+        it "returns whether a path is absolute" do
+          stub_const("RUBY_PLATFORM", "mingw")
+          expect(Util.absolute_path?("/foo")).to be_truthy
+          expect(Util.absolute_path?("\\Windows")).to be_truthy
+          expect(Util.absolute_path?("C:\\Windows")).to be_truthy
+          expect(Util.absolute_path?("f:\\stuff")).to be_truthy
+          expect(Util.absolute_path?("g:/projects")).to be_truthy
+          expect(Util.absolute_path?("x:foo")).to be_falsey
+          expect(Util.absolute_path?("file.txt")).to be_falsey
+        end
+      end
+
+      context "on non-Windows" do
+        it "returns whether a path is absolute" do
+          stub_const("RUBY_PLATFORM", "linux")
+          expect(Util.absolute_path?("/foo")).to be_truthy
+          expect(Util.absolute_path?("\\Windows")).to be_falsey
+          expect(Util.absolute_path?("C:\\Windows")).to be_falsey
+          expect(Util.absolute_path?("f:\\stuff")).to be_falsey
+          expect(Util.absolute_path?("g:/projects")).to be_falsey
+          expect(Util.absolute_path?("x:foo")).to be_falsey
+          expect(Util.absolute_path?("file.txt")).to be_falsey
+        end
+      end
+    end
+
     describe ".make_relative_path" do
       context "when passed a relative path" do
         it "returns the path itself" do
@@ -10,7 +38,7 @@ module Rscons
 
       context "when passed an absolute path" do
         before(:each) do
-          expect(Rscons).to receive(:absolute_path?).and_return(true)
+          expect(Util).to receive(:absolute_path?).and_return(true)
         end
 
         context "on Windows" do
@@ -19,7 +47,7 @@ module Rscons
           end
         end
 
-        context "on POSIX" do
+        context "on non-Windows" do
           it "returns a relative path corresponding to an absolute one" do
             expect(Util.make_relative_path("/foo/bar")).to eq "_/foo/bar"
           end