text: #!/usr/bin/python
  
  # Copyright 2003 Dave Abrahams
  # Copyright 2003, 2006 Vladimir Prus
  # Distributed under the Boost Software License, Version 1.0.
  # (See accompanying file LICENSE_1_0.txt or http://www.boost.org/LICENSE_1_0.txt)
  
  # Test main target alternatives.
  
  import BoostBuild
  import string
  
  t = BoostBuild.Tester(use_test_config=False)
  
  # Test that basic alternatives selection works.
  t.write("jamroot.jam", "")
  
  t.write("jamfile.jam", """
  exe a : a_empty.cpp ;
  exe a : a.cpp : <variant>release ;
  """)
  
  t.write("a_empty.cpp", "")
  
  t.write("a.cpp", "int main() {}\n")
  
  t.run_build_system(["release"])
  
  t.expect_addition("bin/$toolset/release/a.exe")
  
  # Test that alternative selection works for ordinary properties, in particular
  # user-defined.
  t.write("jamroot.jam", "")
  
  t.write("jamfile.jam", """
  import feature ;
  feature.feature X : off on : propagated ;
  exe a : b.cpp ;
  exe a : a.cpp : <X>on ;
  """)
  t.write("b.cpp", "int main() {}\n")
  
  t.rm("bin")
  
  t.run_build_system()
  t.expect_addition("bin/$toolset/debug/b.obj")
  
  t.run_build_system(["X=on"])
  t.expect_addition("bin/$toolset/debug/X-on/a.obj")
  
  t.rm("bin")
  
  # Test that everything works ok even with the default build.
  t.write("jamfile.jam", """\
  exe a : a_empty.cpp : <variant>release ;
  exe a : a.cpp : <variant>debug ;
  """)
  
  t.run_build_system()
  t.expect_addition("bin/$toolset/debug/a.exe")
  
  # Test that only properties which are in the build request matter for
  # alternative selection. IOW, alternative with <variant>release is better than
  # one with <variant>debug when building the release variant.
  t.write("jamfile.jam", """\
  exe a : a_empty.cpp : <variant>debug ;
  exe a : a.cpp : <variant>release ;
  """)
  
  t.run_build_system(["release"])
  t.expect_addition("bin/$toolset/release/a.exe")
  
  # Test that free properties do not matter. We really do not want <cxxflags>
  # property in build request to affect alternative selection.
  t.write("jamfile.jam", """
  exe a : a_empty.cpp : <variant>debug <define>FOO <include>BAR ;
  exe a : a.cpp : <variant>release ;
  """)
  
  t.rm("bin/$toolset/release/a.exe")
  t.run_build_system(["release", "define=FOO"])
  t.expect_addition("bin/$toolset/release/a.exe")
  
  # Test that ambiguity is reported correctly.
  t.write("jamfile.jam", """\
  exe a : a_empty.cpp ;
  exe a : a.cpp ;
  """)
  t.run_build_system(["--no-error-backtrace"], status=None)
  t.fail_test(string.find(t.stdout(), "No best alternative") == -1)
  
  # Another ambiguity test: two matches properties in one alternative are neither
  # better nor worse than a single one in another alternative.
  t.write("jamfile.jam", """\
  exe a : a_empty.cpp : <optimization>off <profiling>off ;
  exe a : a.cpp : <debug-symbols>on ;
  """)
  
  t.run_build_system(["--no-error-backtrace"], status=None)
  t.fail_test(string.find(t.stdout(), "No best alternative") == -1)
  
  # Test that we can have alternative without sources.
  t.write("jamfile.jam", """\
  alias specific-sources ;
  import feature ;
  feature.extend os : MAGIC ;
  alias specific-sources : b.cpp : <os>MAGIC ;
  exe a : a.cpp specific-sources ;
  """)
  t.rm("bin")
  t.run_build_system()
  
  t.cleanup()
  