Support sharding robolectric tests
Explicitly pass the list of tests as LOCAL_ROBOTEST_FILES, and
support sharding the list of tests into multiple test runners.
Also filter out BaseRobolectricTest.java, which covers the only
use of LOCAL_ROBOTEST_FILES in Android.mk files.
Bug: 133878985
Test: m RunSettingsLibRoboTests runs the same number of tests before and after
Test: m RunSettingsLibRoboTests runs the same number of tests when sharded
Change-Id: Id85ffe03c98e722303eaa6def17812ed2244c6a6
diff --git a/java/robolectric_test.go b/java/robolectric_test.go
new file mode 100644
index 0000000..e89c6e7
--- /dev/null
+++ b/java/robolectric_test.go
@@ -0,0 +1,88 @@
+// Copyright 2019 Google Inc. 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.
+
+package java
+
+import (
+ "reflect"
+ "testing"
+)
+
+func Test_shardTests(t *testing.T) {
+ type args struct {
+ paths []string
+ shards int
+ }
+ tests := []struct {
+ name string
+ args args
+ want [][]string
+ }{
+ {
+ name: "empty",
+ args: args{
+ paths: nil,
+ shards: 1,
+ },
+ want: [][]string(nil),
+ },
+ {
+ name: "too many shards",
+ args: args{
+ paths: []string{"a", "b"},
+ shards: 3,
+ },
+ want: [][]string{{"a"}, {"b"}},
+ },
+ {
+ name: "single shard",
+ args: args{
+ paths: []string{"a", "b"},
+ shards: 1,
+ },
+ want: [][]string{{"a", "b"}},
+ },
+ {
+ name: "shard per input",
+ args: args{
+ paths: []string{"a", "b", "c"},
+ shards: 3,
+ },
+ want: [][]string{{"a"}, {"b"}, {"c"}},
+ },
+ {
+ name: "balanced shards",
+ args: args{
+ paths: []string{"a", "b", "c", "d"},
+ shards: 2,
+ },
+ want: [][]string{{"a", "b"}, {"c", "d"}},
+ },
+ {
+ name: "unbalanced shards",
+ args: args{
+ paths: []string{"a", "b", "c"},
+ shards: 2,
+ },
+ want: [][]string{{"a", "b"}, {"c"}},
+ },
+ }
+ for _, tt := range tests {
+ t.Run(tt.name, func(t *testing.T) {
+ if got := shardTests(tt.args.paths, tt.args.shards); !reflect.DeepEqual(got, tt.want) {
+ t.Errorf("shardTests() = %v, want %v", got, tt.want)
+ }
+ })
+ }
+}