bazel-dev is a helper script which attempts to rebuild Bazel on every

execution.

Change-Id: Iaa5168ac8e6c13b0ac5dfc7340c0ccdfc0dcf132

Closes #4932.

Change-Id: I023c83f7373d339c2725e5a4a4b00c9d1dc1a2eb
PiperOrigin-RevId: 190828186

1 files changed, 70 insertions, 0 deletions

diff --git a/scripts/bazel-dev.sh b/scripts/bazel-dev.sh
new file mode 100644
index 0000000000..76ae52bdc6
--- /dev/null
+++ b/scripts/bazel-dev.sh
@@ -0,0 +1,70 @@
+#!/bin/bash
+#
+# Copyright 2018 The Bazel Authors. All rights reserved.
+#
+# 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.
+#
+
+set -eu
+
+USAGE="$0 [<bazel arguments>...]"
+DESCRIPTION='
+  Rebuilds a development version of Bazel, if necessary, and then runs the
+  given Bazel command using that binary.'
+
+function usage() {
+  echo "$USAGE" "$DESCRIPTION" >&2
+}
+
+# Configuration params. Export these in your bashrc to set personal defaults.
+
+# The source of Bazel code.
+BAZEL_REPO=${BAZEL_REPO:-https://github.com/bazelbuild/bazel}
+# Where to keep the Bazel repository. If you make changes here, be warned that
+# this script may overwrite or lose them.
+BAZEL_DIR=${BAZEL_DIR:-$HOME/os-bazel}
+# Bazel to use to build local bazel binaries.
+BAZEL_BINARY=${BAZEL_BINARY:-$(which bazel)}
+
+# The location of the resulting binary.
+BAZEL_DEV="$BAZEL_DIR/bazel-bin/src/bazel"
+
+# First, check whether a rebuild is needed.
+REBUILD=0
+# If there is no built development Bazel, build it.
+if [ ! -x "$BAZEL_DEV" ]; then
+  REBUILD=1
+fi
+# If the current directory isn't the bazel working dir, always try to rebuild.
+if [ "$(pwd)" != "$BAZEL_DIR" ]; then
+  REBUILD=1
+fi
+
+# Perform a rebuild.
+if [ "$REBUILD" == 1 ]; then
+  echo -e "\033[31mBuilding dev version of bazel...\033[0m"
+  (
+    cd "$BAZEL_DIR"
+    result=0
+    ${BAZEL_BINARY} build //src:bazel || result=$?
+    if [[ $result != 0 ]]; then
+      echo -e "\033[31mError building dev version of bazel.\033[0m"
+      exit $result
+    fi
+  )
+fi
+
+# Execute bazel command.
+echo -e "\e[31mExecuting bazel-dev...\e[0m"
+exec $BAZEL_DEV "$@"
+