1 files changed, 166 insertions, 0 deletions
diff --git a/ui/status/critical_path_test.go b/ui/status/critical_path_test.go
new file mode 100644
index 00000000..965e0ad1
--- /dev/null
+++ b/ui/status/critical_path_test.go
@@ -0,0 +1,166 @@
+// 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 status
+
+import (
+	"reflect"
+	"testing"
+	"time"
+)
+
+type testCriticalPath struct {
+	*criticalPath
+	Counts
+
+	actions map[int]*Action
+}
+
+type testClock time.Time
+
+func (t testClock) Now() time.Time { return time.Time(t) }
+
+func (t *testCriticalPath) start(id int, startTime time.Duration, outputs, inputs []string) {
+	t.clock = testClock(time.Unix(0, 0).Add(startTime))
+	action := &Action{
+		Description: outputs[0],
+		Outputs:     outputs,
+		Inputs:      inputs,
+	}
+
+	t.actions[id] = action
+	t.StartAction(action, t.Counts)
+}
+
+func (t *testCriticalPath) finish(id int, endTime time.Duration) {
+	t.clock = testClock(time.Unix(0, 0).Add(endTime))
+	t.FinishAction(ActionResult{
+		Action: t.actions[id],
+	}, t.Counts)
+}
+
+func TestCriticalPath(t *testing.T) {
+	tests := []struct {
+		name     string
+		msgs     func(*testCriticalPath)
+		want     []string
+		wantTime time.Duration
+	}{
+		{
+			name: "empty",
+			msgs: func(cp *testCriticalPath) {},
+		},
+		{
+			name: "duplicate",
+			msgs: func(cp *testCriticalPath) {
+				cp.start(0, 0, []string{"a"}, nil)
+				cp.start(1, 0, []string{"a"}, nil)
+				cp.finish(0, 1000)
+				cp.finish(0, 2000)
+			},
+			want:     []string{"a"},
+			wantTime: 1000,
+		},
+		{
+			name: "linear",
+			//  a
+			//  |
+			//  b
+			//  |
+			//  c
+			msgs: func(cp *testCriticalPath) {
+				cp.start(0, 0, []string{"a"}, nil)
+				cp.finish(0, 1000)
+				cp.start(1, 1000, []string{"b"}, []string{"a"})
+				cp.finish(1, 2000)
+				cp.start(2, 3000, []string{"c"}, []string{"b"})
+				cp.finish(2, 4000)
+			},
+			want:     []string{"c", "b", "a"},
+			wantTime: 3000,
+		},
+		{
+			name: "diamond",
+			//  a
+			//  |\
+			//  b c
+			//  |/
+			//  d
+			msgs: func(cp *testCriticalPath) {
+				cp.start(0, 0, []string{"a"}, nil)
+				cp.finish(0, 1000)
+				cp.start(1, 1000, []string{"b"}, []string{"a"})
+				cp.start(2, 1000, []string{"c"}, []string{"a"})
+				cp.finish(1, 2000)
+				cp.finish(2, 3000)
+				cp.start(3, 3000, []string{"d"}, []string{"b", "c"})
+				cp.finish(3, 4000)
+			},
+			want:     []string{"d", "c", "a"},
+			wantTime: 4000,
+		},
+		{
+			name: "multiple",
+			//  a d
+			//  | |
+			//  b e
+			//  |
+			//  c
+			msgs: func(cp *testCriticalPath) {
+				cp.start(0, 0, []string{"a"}, nil)
+				cp.start(3, 0, []string{"d"}, nil)
+				cp.finish(0, 1000)
+				cp.finish(3, 1000)
+				cp.start(1, 1000, []string{"b"}, []string{"a"})
+				cp.start(4, 1000, []string{"e"}, []string{"d"})
+				cp.finish(1, 2000)
+				cp.start(2, 2000, []string{"c"}, []string{"b"})
+				cp.finish(2, 3000)
+				cp.finish(4, 4000)
+
+			},
+			want:     []string{"e", "d"},
+			wantTime: 4000,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cp := &testCriticalPath{
+				criticalPath: NewCriticalPath(nil).(*criticalPath),
+				actions:      make(map[int]*Action),
+			}
+
+			tt.msgs(cp)
+
+			criticalPath := cp.criticalPath.criticalPath()
+
+			var descs []string
+			for _, x := range criticalPath {
+				descs = append(descs, x.action.Description)
+			}
+
+			if !reflect.DeepEqual(descs, tt.want) {
+				t.Errorf("criticalPath.criticalPath() = %v, want %v", descs, tt.want)
+			}
+
+			var gotTime time.Duration
+			if len(criticalPath) > 0 {
+				gotTime = criticalPath[0].cumulativeDuration
+			}
+			if gotTime != tt.wantTime {
+				t.Errorf("cumulativeDuration[0].cumulativeDuration = %v, want %v", gotTime, tt.wantTime)
+			}
+		})
+	}
+}