[fusl] Add llvm's lit tool to third_party

third_party/lit/utils/check-sdist

+#!/bin/sh
+
+if [ $# = 1 ]; then
+    cd $1
+fi
+
+# Create a list of all the files in the source tree, excluding various things we
+# know don't belong.
+echo "Creating current directory contents list."
+find . | \
+    grep -v '^\./.gitignore' | \
+    grep -v '^\./dist' | \
+    grep -v '^\./utils' | \
+    grep -v '^\./venv' | \
+    grep -v '^\./notes.txt' | \
+    grep -v '^\./lit.egg-info' | \
+    grep -v '^\./lit/ExampleTests' | \
+    grep -v '/Output' | \
+    grep -v '__pycache__' | \
+    grep -v '.pyc$' | grep -v '~$' | \
+    sort > /tmp/lit_source_files.txt
+
+# Create the source distribution.
+echo "Creating source distribution."
+rm -rf lit.egg-info dist
+python setup.py sdist > /tmp/lit_sdist_log.txt
+
+# Creating list of files in source distribution.
+echo "Creating source distribution file list."
+tar zft dist/lit*.tar.gz | \
+    sed -e 's#lit-[0-9.dev]*/#./#' | \
+    sed -e 's#/$##' | \
+    grep -v '^\./PKG-INFO' | \
+    grep -v '^\./setup.cfg' | \
+    grep -v '^\./lit.egg-info' | \
+    sort > /tmp/lit_sdist_files.txt
+
+# Diff the files.
+echo "Running diff..."
+if (diff /tmp/lit_source_files.txt /tmp/lit_sdist_files.txt); then
+    echo "Diff is clean!"
+else
+    echo "error: there were differences in the source lists!"
+    exit 1
+fi