[lit] Move the recursiveExpansionLimit setting to TestingConfig

The LitConfig is shared across the whole test suite. However, since
enabling recursive expansion can be a breaking change for some test
suites, it's important to confine the setting to test suites that
enable it explicitly.

Note that other issues were raised with the way recursiveExpansionLimit
operates. However, this commit simply moves the setting to the right
place -- the mechanism by which it works can be improved independently.

Differential Revision: https://reviews.llvm.org/D77415

libcxx/test/lit.cfg

@@ -20,6 +20,9 @@ config.suffixes = ['.pass.cpp', '.fail.cpp', '.sh.cpp', '.pass.mm']
 # test_source_root: The root path where tests are located.
 config.test_source_root = os.path.dirname(__file__)
 
+# Allow expanding substitutions that are based on other substitutions
+config.recursiveExpansionLimit = 10
+
 loaded_site_cfg = getattr(config, 'loaded_site_config', False)
 if not loaded_site_cfg:
     import libcxx.test.config

libcxx/utils/libcxx/test/format.py

@@ -132,13 +132,13 @@ class LibcxxTestFormat(object):
 
         # Apply substitutions in FILE_DEPENDENCIES markup
         data_files = lit.TestRunner.applySubstitutions(test.file_dependencies, substitutions,
-                                                       recursion_limit=10)
+                                                       recursion_limit=test.config.recursiveExpansionLimit)
         local_cwd = os.path.dirname(test.getSourcePath())
         data_files = [f if os.path.isabs(f) else os.path.join(local_cwd, f) for f in data_files]
         substitutions.append(('%{file_dependencies}', ' '.join(data_files)))
 
         script = lit.TestRunner.applySubstitutions(script, substitutions,
-                                                   recursion_limit=10)
+                                                   recursion_limit=test.config.recursiveExpansionLimit)
 
         test_cxx = copy.deepcopy(self.cxx)
         if is_fail_test:

libcxx/utils/libcxx/test/newformat.py

@@ -191,7 +191,6 @@ class CxxStandardLibraryTest(lit.formats.TestFormat):
 
     # Modified version of lit.TestRunner.executeShTest to handle custom parsers correctly.
     def _executeShTest(self, test, litConfig, steps, fileDependencies=None):
-        recursiveExpansionLimit = 10 # TODO: Use the value in litConfig once we set it.
         if test.config.unsupported:
             return lit.Test.Result(lit.Test.UNSUPPORTED, 'Test is unsupported')
 
@@ -229,7 +228,7 @@ class CxxStandardLibraryTest(lit.formats.TestFormat):
         # need to resolve %{file_dependencies} now, because otherwise we won't be able to
         # make all paths absolute below.
         fileDependencies = lit.TestRunner.applySubstitutions(fileDependencies, substitutions,
-                                                             recursion_limit=recursiveExpansionLimit)
+                                                             recursion_limit=test.config.recursiveExpansionLimit)
 
         # Add the %{file_dependencies} substitution before we perform substitutions
         # inside the script.
@@ -239,6 +238,6 @@ class CxxStandardLibraryTest(lit.formats.TestFormat):
 
         # Perform substitution in the script itself.
         script = lit.TestRunner.applySubstitutions(script, substitutions,
-                                                   recursion_limit=recursiveExpansionLimit)
+                                                   recursion_limit=test.config.recursiveExpansionLimit)
 
         return lit.TestRunner._runShTest(test, litConfig, useExternalSh, script, tmpBase)

libcxxabi/test/lit.cfg

@@ -20,9 +20,15 @@ config.name = 'libc++abi'
 # suffixes: A list of file extensions to treat as test files.
 config.suffixes = ['.cpp', '.s']
 
+# Allow expanding substitutions that are based on other substitutions
+config.recursiveExpansionLimit = 10
+
 # test_source_root: The root path where tests are located.
 config.test_source_root = os.path.dirname(__file__)
 
+# Allow expanding substitutions that are based on other substitutions
+config.recursiveExpansionLimit = 10
+
 # Infer the libcxx_test_source_root for configuration import.
 # If libcxx_source_root isn't specified in the config, assume that the libcxx
 # and libcxxabi source directories are sibling directories.

llvm/docs/CommandGuide/lit.rst

@@ -457,10 +457,10 @@ modules :ref:`local-configuration-files`.
 By default, substitutions are expanded exactly once, so that if e.g. a
 substitution ``%build`` is defined in top of another substitution ``%cxx``,
 ``%build`` will expand to ``%cxx`` textually, not to what ``%cxx`` expands to.
-However, if the ``recursiveExpansionLimit`` property of the ``LitConfig`` is
-set to a non-negative integer, substitutions will be expanded recursively until
-that limit is reached. It is an error if the limit is reached and expanding
-substitutions again would yield a different result.
+However, if the ``recursiveExpansionLimit`` property of the ``TestingConfig``
+is set to a non-negative integer, substitutions will be expanded recursively
+until that limit is reached. It is an error if the limit is reached and
+expanding substitutions again would yield a different result.
 
 More detailed information on substitutions can be found in the
 :doc:`../TestingGuide`.

llvm/utils/lit/lit/LitConfig.py

@@ -66,19 +66,6 @@ class LitConfig(object):
         self.maxIndividualTestTime = maxIndividualTestTime
         self.parallelism_groups = parallelism_groups
         self.echo_all_commands = echo_all_commands
-        self._recursiveExpansionLimit = None
-
-    @property
-    def recursiveExpansionLimit(self):
-        return self._recursiveExpansionLimit
-
-    @recursiveExpansionLimit.setter
-    def recursiveExpansionLimit(self, value):
-        if value is not None and not isinstance(value, int):
-            self.fatal('recursiveExpansionLimit must be either None or an integer (got <{}>)'.format(value))
-        if isinstance(value, int) and value < 0:
-            self.fatal('recursiveExpansionLimit must be a non-negative integer (got <{}>)'.format(value))
-        self._recursiveExpansionLimit = value
 
     @property
     def maxIndividualTestTime(self):

llvm/utils/lit/lit/TestRunner.py

@@ -1552,6 +1552,6 @@ def executeShTest(test, litConfig, useExternalSh,
     substitutions += getDefaultSubstitutions(test, tmpDir, tmpBase,
                                              normalize_slashes=useExternalSh)
     script = applySubstitutions(script, substitutions,
-                                recursion_limit=litConfig.recursiveExpansionLimit)
+                                recursion_limit=test.config.recursiveExpansionLimit)
 
     return _runShTest(test, litConfig, useExternalSh, script, tmpBase)

llvm/utils/lit/lit/TestingConfig.py

@@ -2,7 +2,7 @@ import os
 import sys
 
 
-class TestingConfig:
+class TestingConfig(object):
     """"
     TestingConfig - Information on the tests inside a suite.
     """
@@ -126,6 +126,19 @@ class TestingConfig:
         # Whether the suite should be tested early in a given run.
         self.is_early = bool(is_early)
         self.parallelism_group = parallelism_group
+        self._recursiveExpansionLimit = None
+
+    @property
+    def recursiveExpansionLimit(self):
+        return self._recursiveExpansionLimit
+
+    @recursiveExpansionLimit.setter
+    def recursiveExpansionLimit(self, value):
+        if value is not None and not isinstance(value, int):
+            raise ValueError('recursiveExpansionLimit must be either None or an integer (got <{}>)'.format(value))
+        if isinstance(value, int) and value < 0:
+            raise ValueError('recursiveExpansionLimit must be a non-negative integer (got <{}>)'.format(value))
+        self._recursiveExpansionLimit = value
 
     def finish(self, litConfig):
         """finish() - Finish this config object, after loading is complete."""

llvm/utils/lit/tests/Inputs/shtest-recursive-substitution/does-not-substitute-within-limit/lit.cfg

@@ -9,4 +9,4 @@ config.substitutions = [("%rec1", "STOP"), ("%rec2", "%rec1"),
                         ("%rec3", "%rec2"), ("%rec4", "%rec3"),
                         ("%rec5", "%rec4")]
 
-lit_config.recursiveExpansionLimit = 2
+config.recursiveExpansionLimit = 2

llvm/utils/lit/tests/Inputs/shtest-recursive-substitution/negative-integer/lit.cfg

@@ -5,4 +5,4 @@ config.test_format = lit.formats.ShTest()
 config.test_source_root = None
 config.test_exec_root = None
 
-lit_config.recursiveExpansionLimit = -4
+config.recursiveExpansionLimit = -4

llvm/utils/lit/tests/Inputs/shtest-recursive-substitution/not-an-integer/lit.cfg

@@ -5,4 +5,4 @@ config.test_format = lit.formats.ShTest()
 config.test_source_root = None
 config.test_exec_root = None
 
-lit_config.recursiveExpansionLimit = "not-an-integer"
+config.recursiveExpansionLimit = "not-an-integer"

llvm/utils/lit/tests/Inputs/shtest-recursive-substitution/set-to-none/lit.cfg

@@ -5,4 +5,4 @@ config.test_format = lit.formats.ShTest()
 config.test_source_root = None
 config.test_exec_root = None
 
-lit_config.recursiveExpansionLimit = None
+config.recursiveExpansionLimit = None

llvm/utils/lit/tests/Inputs/shtest-recursive-substitution/substitutes-within-limit/lit.cfg

@@ -9,4 +9,4 @@ config.substitutions = [("%rec1", "STOP"), ("%rec2", "%rec1"),
                         ("%rec3", "%rec2"), ("%rec4", "%rec3"),
                         ("%rec5", "%rec4")]
 
-lit_config.recursiveExpansionLimit = 5
+config.recursiveExpansionLimit = 5