Revert "[lit] Remove dead code not referenced in the LLVM SVN repo."

[modocache]

Summary

This reverts rL306623, which removed FileBasedTest, an abstract base class,
but did not also remove the usages of that class in the lit unit tests.
The revert fixes four test failures in the lit unit test suite.

Test plan:
As per the instructions in utils/lit/README.txt, run the lit unit
test suite:

utils/lit/lit.py \
    --path /path/to/your/llvm/build/bin \
    utils/lit/tests

Verify that the following tests fail before applying this patch, and
pass once the patch is applied:

lit :: test-data.py
lit :: test-output.py
lit :: xunit-output.py

In addition, run check-llvm to make sure the existing LLVM test suite
executes normally.

[mgorny]

LGTM. I've confirmed that it fixes lit test suite, and no additional tests from the LLVM test suite fails (except the one that failed before applying the patch). I haven't tested other LLVM projects though.

[modocache]

Great, thanks @mgorny!

[dlj]

So it looks like I didn't catch these because of https://reviews.llvm.org/rL257268.

It looks to me like lit is back into the list of tests after r309310, so this sort of error should be easy to catch in the future.

utils/lit/lit/formats/__init__.py

-from lit.formats.base import TestFormat  # noqa: F401
+from lit.formats.base import (  # noqa: F401
+    TestFormat,
+    FileBasedTest,
+    OneCommandPerFileTest
+)
+
 from lit.formats.googletest import GoogleTest  # noqa: F401
 from lit.formats.shtest import ShTest  # noqa: F401

utils/lit/lit/formats/base.py

-import abc
+from __future__ import absolute_import
+import os
+
+import lit.Test
+import lit.util
 
 class TestFormat(object):
-    """Base class for test formats.
+    pass
+
+###
+
+class FileBasedTest(TestFormat):
+    def getTestsInDirectory(self, testSuite, path_in_suite,
+                            litConfig, localConfig):
+        source_path = testSuite.getSourcePath(path_in_suite)
+        for filename in os.listdir(source_path):
+            # Ignore dot files and excluded tests.
+            if (filename.startswith('.') or
+                filename in localConfig.excludes):
+                continue
+
+            filepath = os.path.join(source_path, filename)
+            if not os.path.isdir(filepath):
+                base,ext = os.path.splitext(filename)
+                if ext in localConfig.suffixes:
+                    yield lit.Test.Test(testSuite, path_in_suite + (filename,),
+                                        localConfig)
+
+###
+
+import re
+import tempfile
+
+class OneCommandPerFileTest(TestFormat):
+    # FIXME: Refactor into generic test for running some command on a directory
+    # of inputs.
+
+    def __init__(self, command, dir, recursive=False,
+                 pattern=".*", useTempInput=False):
+        if isinstance(command, str):
+            self.command = [command]
+        else:
+            self.command = list(command)
+        if dir is not None:
+            dir = str(dir)
+        self.dir = dir
+        self.recursive = bool(recursive)
+        self.pattern = re.compile(pattern)
+        self.useTempInput = useTempInput
+
+    def getTestsInDirectory(self, testSuite, path_in_suite,
+                            litConfig, localConfig):
+        dir = self.dir
+        if dir is None:
+            dir = testSuite.getSourcePath(path_in_suite)
+
+        for dirname,subdirs,filenames in os.walk(dir):
+            if not self.recursive:
+                subdirs[:] = []
+
+            subdirs[:] = [d for d in subdirs
+                          if (d != '.svn' and
+                              d not in localConfig.excludes)]
+
+            for filename in filenames:
+                if (filename.startswith('.') or
+                    not self.pattern.match(filename) or
+                    filename in localConfig.excludes):
+                    continue
+
+                path = os.path.join(dirname,filename)
+                suffix = path[len(dir):]
+                if suffix.startswith(os.sep):
+                    suffix = suffix[1:]
+                test = lit.Test.Test(
+                    testSuite, path_in_suite + tuple(suffix.split(os.sep)),
+                    localConfig)
+                # FIXME: Hack?
+                test.source_path = path
+                yield test
 
-    A TestFormat encapsulates logic for finding and executing a certain type of
-    test. For example, a subclass FooTestFormat would contain the logic for
-    finding tests written in the 'Foo' format, and the logic for running a
-    single one.
-
-    TestFormat is an Abstract Base Class (ABC). It uses the Python abc.ABCMeta
-    type and associated @abc.abstractmethod decorator. Together, these provide
-    subclass behaviour which is notionally similar to C++ pure virtual classes:
-    only subclasses which implement all abstract methods can be instantiated
-    (the implementation may come from an intermediate base).
-
-    For details on ABCs, see: https://docs.python.org/2/library/abc.html. Note
-    that Python ABCs have extensive abilities beyond what is used here. For
-    TestFormat, we only care about enforcing that abstract methods are
-    implemented.
-    """
-
-    __metaclass__ = abc.ABCMeta
-
-    @abc.abstractmethod
-    def getTestsInDirectory(self, testSuite, path_in_suite, litConfig,
-                            localConfig):
-      """Finds tests of this format in the given directory.
-
-      Args:
-          testSuite: a Test.TestSuite object.
-          path_in_suite: the subpath under testSuite to look for tests.
-          litConfig: the LitConfig for the test suite.
-          localConfig: a LitConfig with local specializations.
-
-      Returns:
-          An iterable of Test.Test objects.
-      """
+    def createTempInput(self, tmp, test):
+        raise NotImplementedError('This is an abstract method.')
 
-    @abc.abstractmethod
     def execute(self, test, litConfig):
-      """Runs the given 'test', which is of this format.
+        if test.config.unsupported:
+            return (lit.Test.UNSUPPORTED, 'Test is unsupported')
+
+        cmd = list(self.command)
+
+        # If using temp input, create a temporary file and hand it to the
+        # subclass.
+        if self.useTempInput:
+            tmp = tempfile.NamedTemporaryFile(suffix='.cpp')
+            self.createTempInput(tmp, test)
+            tmp.flush()
+            cmd.append(tmp.name)
+        elif hasattr(test, 'source_path'):
+            cmd.append(test.source_path)
+        else:
+            cmd.append(test.getSourcePath())
+
+        out, err, exitCode = lit.util.executeCommand(cmd)
+
+        diags = out + err
+        if not exitCode and not diags.strip():
+            return lit.Test.PASS,''
+
+        # Try to include some useful information.
+        report = """Command: %s\n""" % ' '.join(["'%s'" % a
+                                                 for a in cmd])
+        if self.useTempInput:
+            report += """Temporary File: %s\n""" % tmp.name
+            report += "--\n%s--\n""" % open(tmp.name).read()
+        report += """Output:\n--\n%s--""" % diags
 
-      Args:
-          test: a Test.Test object describing the test to run.
-          litConfig: the LitConfig for the test suite.
-
-      Returns:
-          A tuple of (status:Test.ResultCode, message:str)
-      """
+        return lit.Test.FAIL, report

utils/lit/lit/formats/shtest.py

 from __future__ import absolute_import
 
-import os
-
-import lit.Test
 import lit.TestRunner
 import lit.util
-from .base import TestFormat
 
-class ShTest(TestFormat):
+from .base import FileBasedTest
+
+
+class ShTest(FileBasedTest):
     """ShTest is a format with one file per test.
 
     This is the primary format for regression tests as described in the LLVM
     testing guide:
 
         http://llvm.org/docs/TestingGuide.html
 
     The ShTest files contain some number of shell-like command pipelines, along
     with assertions about what should be in the output.
     """
-
-    def __init__(self, execute_external = False):
-        """Initializer.
-
-        The 'execute_external' argument controls whether lit uses its internal
-        logic for command pipelines, or passes the command to a shell
-        subprocess.
-
-        Args:
-            execute_external: (optional) If true, use shell subprocesses instead
-                of lit's internal pipeline logic.
-        """
+    def __init__(self, execute_external=False):
         self.execute_external = execute_external
 
-    def getTestsInDirectory(self, testSuite, path_in_suite,
-                            litConfig, localConfig):
-        """Yields test files matching 'suffixes' from the localConfig."""
-        file_matches = lit.util.listdir_files(
-            testSuite.getSourcePath(path_in_suite),
-            localConfig.suffixes, localConfig.excludes)
-        for filename in file_matches:
-            yield lit.Test.Test(testSuite, path_in_suite + (filename,),
-                                localConfig)
-
     def execute(self, test, litConfig):
-        """Interprets and runs the given test file, and returns the result."""
         return lit.TestRunner.executeShTest(test, litConfig,
                                             self.execute_external)