[lit] Add SKIPPED test result category

Track and print the number of skipped tests.  Skipped tests are tests
that should have been executed but weren't due to:
  * user interrupt [Ctrl+C]
  * --max-time (overall lit timeout)
  * --max-failures

This is part of a larger effort to ensure that all discovered tests are
properly accounted for.

Add test for overall lit timeout feature (`--max-time` option) to
observe skipped tests.  Extend test for `--max-failures` option.

Reviewed By: jdenny

Differential Revision: https://reviews.llvm.org/D77819

utils/lit/lit/Test.py

@@ -36,6 +36,7 @@ XPASS       = ResultCode('XPASS', True)
 UNRESOLVED  = ResultCode('UNRESOLVED', True)
 UNSUPPORTED = ResultCode('UNSUPPORTED', False)
 TIMEOUT     = ResultCode('TIMEOUT', True)
+SKIPPED     = ResultCode('SKIPPED', False)
 
 # Test metric values.
 

utils/lit/lit/main.py

@@ -89,12 +89,14 @@ def main(builtin_params={}):
     run_tests(filtered_tests, lit_config, opts, len(discovered_tests))
     elapsed = time.time() - start
 
-    executed_tests = [t for t in filtered_tests if t.result]
+    # TODO(yln): eventually, all functions below should act on discovered_tests
+    executed_tests = [
+        t for t in filtered_tests if t.result.code != lit.Test.SKIPPED]
 
     if opts.time_tests:
         print_histogram(executed_tests)
 
-    print_results(executed_tests, elapsed, opts)
+    print_results(filtered_tests, elapsed, opts)
 
     if opts.output_path:
         #TODO(yln): pass in discovered_tests
@@ -256,6 +258,7 @@ failure_codes = [
 ]
 
 all_codes = [
+    (lit.Test.SKIPPED,     'Skipped Tests',     'Skipped'),
     (lit.Test.UNSUPPORTED, 'Unsupported Tests', 'Unsupported'),
     (lit.Test.PASS,        'Expected Passes',   ''),
     (lit.Test.FLAKYPASS,   'Passes With Retry', ''),
@@ -277,11 +280,11 @@ def print_results(tests, elapsed, opts):
 def print_group(code, label, tests, opts):
     if not tests:
         return
-    if code == lit.Test.PASS:
+    # TODO(yln): FLAKYPASS? Make this more consistent!
+    if code in {lit.Test.SKIPPED, lit.Test.PASS}:
         return
     if (lit.Test.XFAIL == code and not opts.show_xfail) or \
-       (lit.Test.UNSUPPORTED == code and not opts.show_unsupported) or \
-       (lit.Test.UNRESOLVED == code and (opts.max_failures is not None)):
+       (lit.Test.UNSUPPORTED == code and not opts.show_unsupported):
         return
     print('*' * 20)
     print('%s Tests (%d):' % (label, len(tests)))

utils/lit/lit/run.py

@@ -42,7 +42,7 @@ class Run(object):
 
         Upon completion, each test in the run will have its result
         computed. Tests which were not actually executed (for any reason) will
-        be given an UNRESOLVED result.
+        be marked SKIPPED.
         """
         self.failures = 0
 
@@ -51,12 +51,13 @@ class Run(object):
         timeout = self.timeout or one_week
         deadline = time.time() + timeout
 
-        self._execute(deadline)
-
-        # Mark any tests that weren't run as UNRESOLVED.
-        for test in self.tests:
-            if test.result is None:
-                test.setResult(lit.Test.Result(lit.Test.UNRESOLVED, '', 0.0))
+        try:
+            self._execute(deadline)
+        finally:
+            skipped = lit.Test.Result(lit.Test.SKIPPED)
+            for test in self.tests:
+                if test.result is None:
+                    test.setResult(skipped)
 
     def _execute(self, deadline):
         self._increase_process_limit()

utils/lit/tests/Inputs/max-time/fast.txt

@@ -0,0 +1 @@
+RUN: true

utils/lit/tests/Inputs/max-time/lit.cfg

@@ -0,0 +1,6 @@
+import lit.formats
+config.name = 'lit-time'
+config.suffixes = ['.txt']
+config.test_format = lit.formats.ShTest()
+config.test_source_root = None
+config.test_exec_root = None

utils/lit/tests/Inputs/max-time/slow.txt

@@ -0,0 +1 @@
+RUN: sleep 60

utils/lit/tests/max-failures.py

@@ -1,14 +1,23 @@
 # Check the behavior of --max-failures option.
 #
-# RUN: not %{lit} -j 1 -v %{inputs}/max-failures > %t.out
-# RUN: not %{lit} --max-failures=1 -j 1 -v %{inputs}/max-failures >> %t.out
-# RUN: not %{lit} --max-failures=2 -j 1 -v %{inputs}/max-failures >> %t.out
-# RUN: not %{lit} --max-failures=0 -j 1 -v %{inputs}/max-failures 2>> %t.out
+# RUN: not %{lit}                  -j 1 %{inputs}/max-failures >  %t.out 2>&1
+# RUN: not %{lit} --max-failures=1 -j 1 %{inputs}/max-failures >> %t.out 2>&1
+# RUN: not %{lit} --max-failures=2 -j 1 %{inputs}/max-failures >> %t.out 2>&1
+# RUN: not %{lit} --max-failures=0 -j 1 %{inputs}/max-failures 2>> %t.out
 # RUN: FileCheck < %t.out %s
 #
 # END.
 
-# CHECK: Failing Tests (35)
-# CHECK: Failing Tests (1)
-# CHECK: Failing Tests (2)
+# CHECK-NOT: reached maximum number of test failures
+# CHECK-NOT: Skipped Tests
+# CHECK: Unexpected Failures: 35
+
+# CHECK: reached maximum number of test failures, skipping remaining tests
+# CHECK: Skipped Tests      : 41
+# CHECK: Unexpected Failures:  1
+
+# CHECK: reached maximum number of test failures, skipping remaining tests
+# CHECK: Skipped Tests      : 40
+# CHECK: Unexpected Failures:  2
+
 # CHECK: error: argument --max-failures: requires positive integer, but found '0'

utils/lit/tests/max-time.py

@@ -0,0 +1,7 @@
+# Test overall lit timeout (--max-time).
+#
+# RUN: %{lit} %{inputs}/max-time --max-time=1 2>&1  |  FileCheck %s
+
+# CHECK: reached timeout, skipping remaining tests
+# CHECK: Skipped Tests  : 1
+# CHECK: Expected Passes: 1