lit: allow glob patterns as path arguments

[arichardson]

Summary

This means ./bin/llvm-lit tools/clang/test/CodeGen/*attr* will now
run all the tests inside clang/test/CodeGen that contain attr in the name
instead of lit returning with an error

[chapuni]

It looks good, but I wonder if you weren't satisfied with "bin/llvm-lit path/to/src/clang/test/*attr* ... (I usually use it)

[arichardson]

The last time I tried using a glob on the source directory it did not work for me for some reason. It works now so maybe I was using llvm-lit from the wrong build directory.
However, I still think this patch is useful because it means I don't have to type the full path to the source directory.

[• ddunbar]

What is the motivation for using this, over using the --filter option? I have found --filter to be substantially more general and it is easier for us to support, so my preference would be to move it to be the standard way of solving this problem.

[arichardson]

Not particularly useful.

utils/lit/lit/discovery.py

 """
 Test discovery functions.
 """
 
 import copy
+import glob
 import os
 import sys
 
 import lit.run
 from lit.TestingConfig import TestingConfig
 from lit import LitConfig, Test
 
 def dirContainsTestSuite(path, lit_config):
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):
+        # check if the path is a glob
+        if any(c in source_path for c in ('*', '[', ']', '?')):
+            if litConfig.debug:
+                litConfig.note('Interpreting source path %r as a glob pattern' % source_path)
+            for path in glob.iglob(source_path):
+                ts, path_in_suite = getTestSuite(path, litConfig, testSuiteCache)
+                lc = getLocalConfig(ts, path_in_suite[:-1], litConfig, localConfigCache)
+                yield Test.Test(ts, path_in_suite, lc)
         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