[libc++] Remove the ability to run using the internal Lit shell

The new format requires using an external shell, and as we transition
and we can simplify config.py as we transition to the new format. Also,
frankly, I'd be quite surprised if that setting was still working anyway
because we have several .sh.cpp tests that likely don't work in Lit's
internal shell.

libcxx/utils/libcxx/test/config.py

@@ -76,7 +76,6 @@ class Configuration(object):
         self.use_system_cxx_lib = False
         self.use_clang_verify = False
         self.long_tests = None
-        self.execute_external = False
 
     def get_lit_conf(self, name, default=None):
         val = self.lit_config.params.get(name, None)
@@ -133,7 +132,6 @@ class Configuration(object):
         self.configure_cxx_library_root()
         self.configure_use_clang_verify()
         self.configure_use_thread_safety()
-        self.configure_execute_external()
         self.configure_ccache()
         self.configure_compile_flags()
         self.configure_link_flags()
@@ -177,7 +175,6 @@ class Configuration(object):
         return LibcxxTestFormat(
             self.cxx,
             self.use_clang_verify,
-            self.execute_external,
             self.executor,
             exec_env=self.exec_env)
 
@@ -346,21 +343,6 @@ class Configuration(object):
             self.config.available_features.add('thread-safety')
             self.lit_config.note("enabling thread-safety annotations")
 
-    def configure_execute_external(self):
-        # Choose between lit's internal shell pipeline runner and a real shell.
-        # If LIT_USE_INTERNAL_SHELL is in the environment, we use that as the
-        # default value. Otherwise we ask the target_info.
-        use_lit_shell_default = os.environ.get('LIT_USE_INTERNAL_SHELL')
-        if use_lit_shell_default is not None:
-            use_lit_shell_default = use_lit_shell_default != '0'
-        else:
-            use_lit_shell_default = self.target_info.use_lit_shell_default()
-        # Check for the command line parameter using the default value if it is
-        # not present.
-        use_lit_shell = self.get_lit_bool('use_lit_shell',
-                                          use_lit_shell_default)
-        self.execute_external = not use_lit_shell
-
     def configure_ccache(self):
         use_ccache_default = os.environ.get('LIBCXX_USE_CCACHE') is not None
         use_ccache = self.get_lit_bool('use_ccache', use_ccache_default)

libcxx/utils/libcxx/test/format.py

@@ -35,11 +35,10 @@ class LibcxxTestFormat(object):
       FOO.sh.cpp   - A test that uses LIT's ShTest format.
     """
 
-    def __init__(self, cxx, use_verify_for_fail, execute_external,
+    def __init__(self, cxx, use_verify_for_fail,
                  executor, exec_env):
         self.cxx = copy.deepcopy(cxx)
         self.use_verify_for_fail = use_verify_for_fail
-        self.execute_external = execute_external
         self.executor = executor
         self.exec_env = dict(exec_env)
 
@@ -126,7 +125,7 @@ class LibcxxTestFormat(object):
 
         tmpDir, tmpBase = lit.TestRunner.getTempPaths(test)
         substitutions = lit.TestRunner.getDefaultSubstitutions(
-            test, tmpDir, tmpBase, normalize_slashes=self.execute_external)
+            test, tmpDir, tmpBase, normalize_slashes=True)
 
         # Apply substitutions in FILE_DEPENDENCIES markup
         data_files = lit.TestRunner.applySubstitutions(test.file_dependencies, substitutions,
@@ -172,7 +171,7 @@ class LibcxxTestFormat(object):
                 return lit.Test.UNSUPPORTED, 'ShTest format not yet supported'
             test.config.environment = self.executor.merge_environments(os.environ, self.exec_env)
             return lit.TestRunner._runShTest(test, lit_config,
-                                             self.execute_external, script,
+                                             True, script,
                                              tmpBase)
         elif is_fail_test:
             return self._evaluate_fail_test(test, test_cxx, parsers)