Refactor queryview.

Splits queryview into queryview and bp2build. The latter runs as a
presingleton (could be converted to a singleton). This prevents needing
to run soong_ui a subsequent time to build the query. Queryview remains
as a separate step to prevent increasing runtime due to this generation
every time Soong runs.

Currently this is running as a presingleton as this gives a translation
of Android.bp files after only LoadHooks have run, no mutators.

Test: go tests
Test: m queryview && bazel query --config=queryview //...
Change-Id: If2ba28c7ef60fbd41f43bda6623d41c8c7d23a1b

bp2build/conversion_test.go

@@ -0,0 +1,73 @@
+// Copyright 2020 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 bp2build
+
+import (
+	"sort"
+	"testing"
+)
+
+func TestCreateBazelFiles_AddsTopLevelFiles(t *testing.T) {
+	files := CreateBazelFiles(map[string]RuleShim{}, map[string][]BazelTarget{})
+	expectedFilePaths := []struct {
+		dir      string
+		basename string
+	}{
+		{
+			dir:      "",
+			basename: "BUILD",
+		},
+		{
+			dir:      "",
+			basename: "WORKSPACE",
+		},
+		{
+			dir:      bazelRulesSubDir,
+			basename: "BUILD",
+		},
+		{
+			dir:      bazelRulesSubDir,
+			basename: "providers.bzl",
+		},
+		{
+			dir:      bazelRulesSubDir,
+			basename: "soong_module.bzl",
+		},
+	}
+
+	if g, w := len(files), len(expectedFilePaths); g != w {
+		t.Errorf("Expected %d files, got %d", w, g)
+	}
+
+	sort.Slice(files, func(i, j int) bool {
+		if dir1, dir2 := files[i].Dir, files[j].Dir; dir1 == dir2 {
+			return files[i].Basename < files[j].Basename
+		} else {
+			return dir1 < dir2
+		}
+	})
+
+	for i := range files {
+		if g, w := files[i], expectedFilePaths[i]; g.Dir != w.dir || g.Basename != w.basename {
+			t.Errorf("Did not find expected file %s/%s", g.Dir, g.Basename)
+		} else if g.Basename == "BUILD" || g.Basename == "WORKSPACE" {
+			if g.Contents != "" {
+				t.Errorf("Expected %s to have no content.", g)
+			}
+		} else if g.Contents == "" {
+			t.Errorf("Contents of %s unexpected empty.", g)
+		}
+	}
+}