Support patches in http_archive

Support applying a sequence of patches for external repositories
imported via http_archive. (Note that we only support the version
from @bazel_tools, not the deprecated native rules.)

Works towards #3395.

Change-Id: I96c746acc04790b051eb686856c04a3ff3c90059
PiperOrigin-RevId: 181975322

2 files changed, 100 insertions, 0 deletions

diff --git a/src/test/shell/bazel/BUILD b/src/test/shell/bazel/BUILD
index 6c25dfd00b..d39cf7d77d 100644
--- a/src/test/shell/bazel/BUILD
+++ b/src/test/shell/bazel/BUILD
@@ -241,6 +241,13 @@ sh_test(
 )
 
 sh_test(
+    name = "external_patching_test",
+    size = "medium",
+    srcs = ["external_patching_test.sh"],
+    data = [":test-deps"],
+)
+
+sh_test(
     name = "git_repository_test",
     size = "large",
     srcs = ["git_repository_test.sh"],
diff --git a/src/test/shell/bazel/external_patching_test.sh b/src/test/shell/bazel/external_patching_test.sh
new file mode 100755
index 0000000000..5e44ab23e2
--- /dev/null
+++ b/src/test/shell/bazel/external_patching_test.sh
@@ -0,0 +1,93 @@
+#!/bin/bash
+#
+# Copyright 2017 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.
+#
+# Tests the patching functionality of external repositories.
+
+# Load the test setup defined in the parent directory
+CURRENT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+source "${CURRENT_DIR}/../integration_test_setup.sh" \
+  || { echo "integration_test_setup.sh not found!" >&2; exit 1; }
+source "${CURRENT_DIR}/remote_helpers.sh" \
+  || { echo "remote_helpers.sh not found!" >&2; exit 1; }
+
+
+set_up() {
+  # create an archive file with files interesting for patching
+  mkdir ext-0.1.2
+  cat > ext-0.1.2/foo.sh <<'EOF'
+#!/usr/bin/env sh
+
+echo Here be dragons...
+EOF
+  zip ext.zip ext-0.1.2/*
+  rm -rf ext-0.1.2
+}
+
+
+test_patch_file() {
+  EXTREPODIR=`pwd`
+
+  # Test that the patches attribute of http_archive is honored
+  mkdir main
+  cd main
+  cat > patch_foo.sh <<'EOF'
+--- foo.sh.orig	2018-01-15 10:39:20.183909147 +0100
++++ foo.sh	2018-01-15 10:43:35.331566052 +0100
+@@ -1,3 +1,3 @@
+ #!/usr/bin/env sh
+
+-echo Here be dragons...
++echo There are dragons...
+EOF
+  cat > WORKSPACE <<EOF
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+http_archive(
+  name="ext",
+  strip_prefix="ext-0.1.2",
+  urls=["file://${EXTREPODIR}/ext.zip"],
+  build_file_content="exports_files([\"foo.sh\"])",
+  patches = ["//:patch_foo.sh"],
+)
+EOF
+  cat > BUILD <<'EOF'
+genrule(
+  name = "foo",
+  outs = ["foo.sh"],
+  srcs = ["@ext//:foo.sh"],
+  cmd = "cp $< $@; chmod u+x $@",
+  executable = True,
+)
+EOF
+  bazel build :foo.sh
+  foopath=`bazel info bazel-genfiles`/foo.sh
+  grep -q 'There are' $foopath || fail "expected patch to be applied"
+
+  # Verify that changes to the patches attribute trigger enough rebuilding
+  cat > WORKSPACE <<EOF
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+http_archive(
+  name="ext",
+  strip_prefix="ext-0.1.2",
+  urls=["file://${EXTREPODIR}/ext.zip"],
+  build_file_content="exports_files([\"foo.sh\"])",
+)
+EOF
+  bazel build :foo.sh
+  foopath=`bazel info bazel-genfiles`/foo.sh
+  grep -q 'Here be' $foopath || fail "expected unpatched file"
+}
+
+run_suite "external patching tests"