Restore autoconf_false test

build_tests/configure/autoconf_false.rb

@@ -0,0 +1,3 @@
+autoconf false
+Environment.new do |env|
+end

spec/build_tests_spec.rb

@@ -2365,6 +2365,13 @@ EOF
       expect(result.stdout).to match /gcc.*-o.*\.o.*-DHAVE_MATH_H\s.*-DHAVE_STDIO_H/
     end
 
+    it "exits with an error if the project is not configured and a build is requested and autoconf is false" do
+      test_dir "configure"
+      result = run_rscons(args: %w[-f autoconf_false.rb])
+      expect(result.stderr).to match /Project must be configured before creating an Environment/
+      expect(result.status).to_not eq 0
+    end
+
     it "exits with an error code and message if configuration fails during autoconf" do
       test_dir "configure"
       result = run_rscons(args: %w[-f autoconf_fail.rb])