chore: add shell script simulating the developer experience

Author: alexeagle

examples/foo.pb.go

@@ -5,5 +5,4 @@ package foo;
 message Foo {
     string name = 1;
     string description = 2;
-    int32 age = 3;
 }

examples/foo.proto

@@ -0,0 +1,38 @@
+#!/usr/bin/env bash
+#
+# Shows an end-to-end workflow for accepting new patches without failing the build.
+set -o errexit -o pipefail -o nounset
+
+if [ "$#" -eq 0 ]; then
+	echo "usage: test.sh [target pattern...]"
+	exit 1
+fi
+
+fix=""
+buildevents=$(mktemp)
+filter='.namedSetOfFiles | values | .files[] | select(.name | endswith($ext)) | ((.pathPrefix | join("/")) + "/" + .name)'
+
+args=(
+    "--keep_going"
+    "--output_groups=diff_bzl__patch"
+	"--build_event_json_file=$buildevents"
+	"--remote_download_regex='.*\.patch'"
+)
+
+# Run build with validation disabled and output group for patches.
+# This will present us with patches to apply
+if ! bazel build ${args[@]} $@; then
+    echo "Build failed, applying patches"
+    to_apply_patches=$(jq --arg ext .patch --raw-output "$filter" "$buildevents" | tr -d '\r')
+    wksp=$(bazel info workspace)
+    for patch in $to_apply_patches; do
+        # continue if patch file content is empty
+        if [[ ! -s "${wksp}/${patch}" ]]; then
+            continue
+        fi
+        echo "Applying patch ${patch}"
+        patch -d ${wksp} -p0 <${wksp}/${patch}
+    done
+fi
+
+exec bazel test $@