Add tools/test_all.sh

We should look into having a `ninja check-npcomp` that runs everything
with lit so that we get decent test multithreading.
We can look to how LLVM does its gtest tests ("unittests") for
inspiration.

README.md

@@ -31,6 +31,8 @@ export LLVM_SRC_DIR=/path/to/llvm-project
 ./tools/install_mlir.sh
 ./tools/cmake_configure.sh
 
+
+# ./tools/test_all.sh runs all of these commands.
 cd build
 ninja
 ninja check-npcomp-opt

tools/test_all.sh

@@ -0,0 +1,31 @@
+#!/bin/bash
+
+# Runs all the tests we are aware of in mlir-npcomp.
+# TODO: This should eventually all be folded into a `ninja check-npcomp`.
+# Unfortunately, that seems to be a level of build engineering that we
+# haven't had enough bandwidth for.
+#
+# The basic idea seems to be to teach `lit` how to run our Python tests.
+#
+# There is precendent for doing this, e.g.
+# - For GoogleTest tests (i.e. "unittests"): https://github.com/llvm/llvm-project/blob/c490c5e81ac90cbf079c7cee18cd56171f1e27af/llvm/test/Unit/lit.cfg.py#L25
+# - LLDB tests: https://github.com/llvm/llvm-project/blob/eb7d32e46fe184fdfcb52e0a25973e713047e305/lldb/test/API/lldbtest.py#L32
+# - libcxx tests: https://github.com/llvm/llvm-project/blob/eb7d32e46fe184fdfcb52e0a25973e713047e305/libcxx/utils/libcxx/test/newformat.py#L192
+#
+# The `getTestsInDirectory` keyword seems to be what to search for.
+
+set -euo pipefail
+td="$(realpath $(dirname $0)/..)"
+
+cd $td/build
+
+ninja
+ninja check-npcomp-opt
+./python/run_tests.py
+
+echo
+echo "========"
+echo "ALL PASS"
+echo "========"
+
+