Use relative path/dir msbuild variables to map $(InputDir) and $(InputPath)

test/rules-dirname/gyptest-dirname.py

Index: test/rules-dirname/gyptest-dirname.py
diff --git a/test/rules-dirname/gyptest-dirname.py b/test/rules-dirname/gyptest-dirname.py
index 46f3a1b5b2a474413f3d6d963f96bedb7eca5cbb..420b80f05c5f22457df8133f8ee3a3474c66453e 100755
--- a/test/rules-dirname/gyptest-dirname.py
+++ b/test/rules-dirname/gyptest-dirname.py
@@ -10,8 +10,9 @@ Verifies simple rules when using an explicit build target of 'all'.
 
 import TestGyp
 import os
+import sys
 
-test = TestGyp.TestGyp(formats=['make', 'ninja', 'android', 'xcode'])
+test = TestGyp.TestGyp(formats=['make', 'ninja', 'android', 'xcode', 'msvs'])
 
 test.run_gyp('actions.gyp', chdir='src')
 
@@ -29,9 +30,21 @@ if test.format == 'xcode':
 else:
   chdir = 'relocate/src'
 test.run_built_executable('gencc_int_output', chdir=chdir, stdout=expect)
+if test.format == 'msvs':
+  test.run_built_executable('gencc_int_output_external', chdir=chdir,
+                            stdout=expect)
 
-test.must_match('relocate/src/subdir/foo/bar/baz.printed',
+test.must_match('relocate/src/subdir/foo/bar/baz.dirname',
                 os.path.join('foo', 'bar'))
-test.must_match('relocate/src/subdir/a/b/c.printed', os.path.join('a', 'b'))
+test.must_match('relocate/src/subdir/a/b/c.dirname',
+                os.path.join('a', 'b'))
+
+# FIXME the xcode and make generators incorrectly convert RULE_INPUT_PATH
+# to an absolute path, making the tests below fail!
+if test.format != 'xcode' and test.format != 'make':
+  test.must_match('relocate/src/subdir/foo/bar/baz.path',
+                  os.path.join('foo', 'bar', 'baz.printvars'))
+  test.must_match('relocate/src/subdir/a/b/c.path',
+                  os.path.join('a', 'b', 'c.printvars'))
 
 test.pass_test()