Generate build-globs.ninja when running bp2build.

This fixes null bp2build builds.

When running bp2build, out/soong/.bootstrap/build-globs.ninja wasn't
generated, therefore none of the globs in out/soong/.primary/globs have
actions to generate them. This makes bp2build always re-run on a null
build, because it depends on those non-existent globs in its depfile.

Fix the above by generating a build-globs.ninja file with the globs that
bp2build encounters during conversion, and add tests to verify that null
builds and bp2build -> soong workflows correctly regenerates the
build-globs.ninja file.

Test: soong integration tests for null soong->soong, bp2build->bp2build and bp2build->soong builds.
Fixes: 193650250
Change-Id: Icfbad351dfa85541d1ea451f73e65cac87097926

2 files changed, 100 insertions, 0 deletions

diff --git a/cmd/soong_build/main.go b/cmd/soong_build/main.go
index 0336fb668..0099e877e 100644
--- a/cmd/soong_build/main.go
+++ b/cmd/soong_build/main.go
@@ -469,6 +469,12 @@ func runBp2Build(configuration android.Config, extraNinjaDeps []string) {
 	ninjaDeps := bootstrap.RunBlueprint(blueprintArgs, bp2buildCtx.Context, configuration)
 	ninjaDeps = append(ninjaDeps, extraNinjaDeps...)
 
+	// Generate out/soong/.bootstrap/build-globs.ninja with the actions to generate flattened globfiles
+	// containing the globs seen during bp2build conversion
+	if blueprintArgs.GlobFile != "" {
+		bootstrap.WriteBuildGlobsNinjaFile(bootstrap.StageMain, bp2buildCtx.Context, blueprintArgs, configuration)
+	}
+	// Add the depfile on the expanded globs in out/soong/.primary/globs
 	ninjaDeps = append(ninjaDeps, bootstrap.GlobFileListFiles(configuration)...)
 
 	// Run the code-generation phase to convert BazelTargetModules to BUILD files
diff --git a/tests/bp2build_bazel_test.sh b/tests/bp2build_bazel_test.sh
index e3577107f..b5c686311 100755
--- a/tests/bp2build_bazel_test.sh
+++ b/tests/bp2build_bazel_test.sh
@@ -8,6 +8,100 @@ source "$(dirname "$0")/lib.sh"
 
 readonly GENERATED_BUILD_FILE_NAME="BUILD.bazel"
 
+function test_bp2build_null_build() {
+  setup
+  run_bp2build
+  local output_mtime1=$(stat -c "%y" out/soong/.bootstrap/bp2build_workspace_marker)
+
+  run_bp2build
+  local output_mtime2=$(stat -c "%y" out/soong/.bootstrap/bp2build_workspace_marker)
+
+  if [[ "$output_mtime1" != "$output_mtime2" ]]; then
+    fail "Output bp2build marker file changed on null build"
+  fi
+}
+
+test_bp2build_null_build
+
+function test_bp2build_null_build_with_globs() {
+  setup
+
+  mkdir -p foo/bar
+  cat > foo/bar/Android.bp <<'EOF'
+filegroup {
+    name: "globs",
+    srcs: ["*.txt"],
+  }
+EOF
+  touch foo/bar/a.txt foo/bar/b.txt
+
+  run_bp2build
+  local output_mtime1=$(stat -c "%y" out/soong/.bootstrap/bp2build_workspace_marker)
+
+  run_bp2build
+  local output_mtime2=$(stat -c "%y" out/soong/.bootstrap/bp2build_workspace_marker)
+
+  if [[ "$output_mtime1" != "$output_mtime2" ]]; then
+    fail "Output bp2build marker file changed on null build"
+  fi
+}
+
+test_bp2build_null_build_with_globs
+
+function test_soong_after_bp2build_regenerates_build_globs_ninja() {
+  setup
+
+  mkdir -p foo/bar
+  cat > foo/bar/Android.bp <<'EOF'
+filegroup {
+    name: "bp2build-files",
+    srcs: ["bp2build.*"],
+    bazel_module: { bp2build_available: true },
+}
+
+filegroup {
+    name: "soong-files",
+    srcs: ["soong.*"],
+}
+EOF
+  touch foo/bar/bp2build.txt foo/bar/soong.txt
+
+  build_globs_file="out/soong/.bootstrap/build-globs.ninja"
+
+  # Test: the build-globs file for bp2build should only contain the bp2build-files
+  # glob, whereas the build-globs file for soong should contain both bp2build-files
+  # and soong-files globs.
+
+  run_bp2build
+  local output_mtime1=$(stat -c "%y" "${build_globs_file}")
+
+  if ! grep "\"foo/bar/bp2build.*\"" "${build_globs_file}"; then
+    fail "bp2build filegroup globs not found in bp2build's globs file"
+  fi
+
+  if grep "\"foo/bar/soong.*\"" "${build_globs_file}"; then
+    fail "soong filegroup globs unexpectedly found in bp2build's globs file"
+  fi
+
+  run_soong
+  local output_mtime2=$(stat -c "%y" "${build_globs_file}")
+
+  if [[ "$output_mtime1" == "$output_mtime2" ]]; then
+    fail "Output build-globs.ninja file did not change"
+  fi
+
+  if ! grep "\"foo/bar/bp2build.*\"" "${build_globs_file}"; then
+    fail "bp2build filegroup globs not found in bp2build's globs file"
+  fi
+
+  if ! grep "\"foo/bar/soong.*\"" "${build_globs_file}"; then
+    fail "soong filegroup globs not found in bp2build's globs file"
+  fi
+
+}
+
+test_soong_after_bp2build_regenerates_build_globs_ninja
+
 function test_bp2build_generates_all_buildfiles {
   setup
   create_mock_bazel