Enable license checking. (#42)

We use a simple license checker script, which points out which files miss the license header (also provided).

Author: mtrofin

.github/workflows/main.yml

@@ -31,3 +31,6 @@ jobs:
       - name: Lint
         run: |
           pylint --rcfile .pylintrc --recursive yes .
+      - name: Check License Header
+        run: |
+          ./check-license.sh

check-license.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+exitcode=0
+for fname in `find . -name "*.py"`; 
+do
+  diff -q <(head -14 $fname) <(cat license-header.txt) > /dev/null
+  if [ $? -ne 0 ]
+  then
+    echo "$fname does not have license header. Please copy and paste ./license-header.txt"
+    exitcode=1
+  fi
+done
+exit ${exitcode}

compiler_opt/tools/__init__.py

@@ -0,0 +1,14 @@
+# coding=utf-8
+# Copyright 2020 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.

license-header.txt

@@ -0,0 +1,14 @@
+# coding=utf-8
+# Copyright 2020 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.