[fusl] Add llvm's lit tool to third_party

third_party/lit/lit/discovery.py

Index: third_party/lit/lit/discovery.py
diff --git a/third_party/lit/lit/discovery.py b/third_party/lit/lit/discovery.py
new file mode 100644
index 0000000000000000000000000000000000000000..4befe582d454c37dfb33c1f302793695bafa0fe0
--- /dev/null
+++ b/third_party/lit/lit/discovery.py
@@ -0,0 +1,255 @@
+"""
+Test discovery functions.
+"""
+
+import copy
+import os
+import sys
+
+import lit.run
+from lit.TestingConfig import TestingConfig
+from lit import LitConfig, Test
+
+def dirContainsTestSuite(path, lit_config):
+    cfgpath = os.path.join(path, lit_config.site_config_name)
+    if os.path.exists(cfgpath):
+        return cfgpath
+    cfgpath = os.path.join(path, lit_config.config_name)
+    if os.path.exists(cfgpath):
+        return cfgpath
+
+def getTestSuite(item, litConfig, cache):
+    """getTestSuite(item, litConfig, cache) -> (suite, relative_path)
+
+    Find the test suite containing @arg item.
+
+    @retval (None, ...) - Indicates no test suite contains @arg item.
+    @retval (suite, relative_path) - The suite that @arg item is in, and its
+    relative path inside that suite.
+    """
+    def search1(path):
+        # Check for a site config or a lit config.
+        cfgpath = dirContainsTestSuite(path, litConfig)
+
+        # If we didn't find a config file, keep looking.
+        if not cfgpath:
+            parent,base = os.path.split(path)
+            if parent == path:
+                return (None, ())
+
+            ts, relative = search(parent)
+            return (ts, relative + (base,))
+
+        # We found a test suite, create a new config for it and load it.
+        if litConfig.debug:
+            litConfig.note('loading suite config %r' % cfgpath)
+
+        cfg = TestingConfig.fromdefaults(litConfig)
+        cfg.load_from_path(cfgpath, litConfig)
+        source_root = os.path.realpath(cfg.test_source_root or path)
+        exec_root = os.path.realpath(cfg.test_exec_root or path)
+        return Test.TestSuite(cfg.name, source_root, exec_root, cfg), ()
+
+    def search(path):
+        # Check for an already instantiated test suite.
+        res = cache.get(path)
+        if res is None:
+            cache[path] = res = search1(path)
+        return res
+
+    # Canonicalize the path.
+    item = os.path.realpath(item)
+
+    # Skip files and virtual components.
+    components = []
+    while not os.path.isdir(item):
+        parent,base = os.path.split(item)
+        if parent == item:
+            return (None, ())
+        components.append(base)
+        item = parent
+    components.reverse()
+
+    ts, relative = search(item)
+    return ts, tuple(relative + tuple(components))
+
+def getLocalConfig(ts, path_in_suite, litConfig, cache):
+    def search1(path_in_suite):
+        # Get the parent config.
+        if not path_in_suite:
+            parent = ts.config
+        else:
+            parent = search(path_in_suite[:-1])
+
+        # Check if there is a local configuration file.
+        source_path = ts.getSourcePath(path_in_suite)
+        cfgpath = os.path.join(source_path, litConfig.local_config_name)
+
+        # If not, just reuse the parent config.
+        if not os.path.exists(cfgpath):
+            return parent
+
+        # Otherwise, copy the current config and load the local configuration
+        # file into it.
+        config = copy.deepcopy(parent)
+        if litConfig.debug:
+            litConfig.note('loading local config %r' % cfgpath)
+        config.load_from_path(cfgpath, litConfig)
+        return config
+
+    def search(path_in_suite):
+        key = (ts, path_in_suite)
+        res = cache.get(key)
+        if res is None:
+            cache[key] = res = search1(path_in_suite)
+        return res
+
+    return search(path_in_suite)
+
+def getTests(path, litConfig, testSuiteCache, localConfigCache):
+    # Find the test suite for this input and its relative path.
+    ts,path_in_suite = getTestSuite(path, litConfig, testSuiteCache)
+    if ts is None:
+        litConfig.warning('unable to find test suite for %r' % path)
+        return (),()
+
+    if litConfig.debug:
+        litConfig.note('resolved input %r to %r::%r' % (path, ts.name,
+                                                        path_in_suite))
+
+    return ts, getTestsInSuite(ts, path_in_suite, litConfig,
+                               testSuiteCache, localConfigCache)
+
+def getTestsInSuite(ts, path_in_suite, litConfig,
+                    testSuiteCache, localConfigCache):
+    # Check that the source path exists (errors here are reported by the
+    # caller).
+    source_path = ts.getSourcePath(path_in_suite)
+    if not os.path.exists(source_path):
+        return
+
+    # Check if the user named a test directly.
+    if not os.path.isdir(source_path):
+        lc = getLocalConfig(ts, path_in_suite[:-1], litConfig, localConfigCache)
+        yield Test.Test(ts, path_in_suite, lc)
+        return
+
+    # Otherwise we have a directory to search for tests, start by getting the
+    # local configuration.
+    lc = getLocalConfig(ts, path_in_suite, litConfig, localConfigCache)
+
+    # Search for tests.
+    if lc.test_format is not None:
+        for res in lc.test_format.getTestsInDirectory(ts, path_in_suite,
+                                                      litConfig, lc):
+            yield res
+
+    # Search subdirectories.
+    for filename in os.listdir(source_path):
+        # FIXME: This doesn't belong here?
+        if filename in ('Output', '.svn', '.git') or filename in lc.excludes:
+            continue
+
+        # Ignore non-directories.
+        file_sourcepath = os.path.join(source_path, filename)
+        if not os.path.isdir(file_sourcepath):
+            continue
+
+        # Check for nested test suites, first in the execpath in case there is a
+        # site configuration and then in the source path.
+        subpath = path_in_suite + (filename,)
+        file_execpath = ts.getExecPath(subpath)
+        if dirContainsTestSuite(file_execpath, litConfig):
+            sub_ts, subpath_in_suite = getTestSuite(file_execpath, litConfig,
+                                                    testSuiteCache)
+        elif dirContainsTestSuite(file_sourcepath, litConfig):
+            sub_ts, subpath_in_suite = getTestSuite(file_sourcepath, litConfig,
+                                                    testSuiteCache)
+        else:
+            sub_ts = None
+
+        # If the this directory recursively maps back to the current test suite,
+        # disregard it (this can happen if the exec root is located inside the
+        # current test suite, for example).
+        if sub_ts is ts:
+            continue
+
+        # Otherwise, load from the nested test suite, if present.
+        if sub_ts is not None:
+            subiter = getTestsInSuite(sub_ts, subpath_in_suite, litConfig,
+                                      testSuiteCache, localConfigCache)
+        else:
+            subiter = getTestsInSuite(ts, subpath, litConfig, testSuiteCache,
+                                      localConfigCache)
+
+        N = 0
+        for res in subiter:
+            N += 1
+            yield res
+        if sub_ts and not N:
+            litConfig.warning('test suite %r contained no tests' % sub_ts.name)
+
+def find_tests_for_inputs(lit_config, inputs):
+    """
+    find_tests_for_inputs(lit_config, inputs) -> [Test]
+
+    Given a configuration object and a list of input specifiers, find all the
+    tests to execute.
+    """
+
+    # Expand '@...' form in inputs.
+    actual_inputs = []
+    for input in inputs:
+        if input.startswith('@'):
+            f = open(input[1:])
+            try:
+                for ln in f:
+                    ln = ln.strip()
+                    if ln:
+                        actual_inputs.append(ln)
+            finally:
+                f.close()
+        else:
+            actual_inputs.append(input)
+                    
+    # Load the tests from the inputs.
+    tests = []
+    test_suite_cache = {}
+    local_config_cache = {}
+    for input in actual_inputs:
+        prev = len(tests)
+        tests.extend(getTests(input, lit_config,
+                              test_suite_cache, local_config_cache)[1])
+        if prev == len(tests):
+            lit_config.warning('input %r contained no tests' % input)
+
+    # If there were any errors during test discovery, exit now.
+    if lit_config.numErrors:
+        sys.stderr.write('%d errors, exiting.\n' % lit_config.numErrors)
+        sys.exit(2)
+
+    return tests
+
+def load_test_suite(inputs):
+    import platform
+    import unittest
+    from lit.LitTestCase import LitTestCase
+
+    # Create the global config object.
+    litConfig = LitConfig.LitConfig(progname = 'lit',
+                                    path = [],
+                                    quiet = False,
+                                    useValgrind = False,
+                                    valgrindLeakCheck = False,
+                                    valgrindArgs = [],
+                                    noExecute = False,
+                                    debug = False,
+                                    isWindows = (platform.system()=='Windows'),
+                                    params = {})
+
+    # Perform test discovery.
+    run = lit.run.Run(litConfig, find_tests_for_inputs(litConfig, inputs))
+
+    # Return a unittest test suite which just runs the tests in order.
+    return unittest.TestSuite([LitTestCase(test, run)
+                               for test in run.tests])