Add a --hermetic_java_home= flag to singlejar

PiperOrigin-RevId: 445519501

Author: cushon

src/tools/singlejar/options.cc

@@ -55,7 +55,8 @@ bool Options::ParseToken(ArgTokenStream *tokens) {
                           &warn_duplicate_resources) ||
       tokens->MatchAndSet("--nocompress_suffixes", &nocompress_suffixes) ||
       tokens->MatchAndSet("--check_desugar_deps", &check_desugar_deps) ||
-      tokens->MatchAndSet("--multi_release", &multi_release)) {
+      tokens->MatchAndSet("--multi_release", &multi_release) ||
+      tokens->MatchAndSet("--hermetic_java_home", &hermetic_java_home)) {
     return true;
   } else if (tokens->MatchAndSet("--build_info_file", &optarg)) {
     build_info_files.push_back(optarg);

src/tools/singlejar/options.h

@@ -65,6 +65,7 @@ class Options {
   bool warn_duplicate_resources;
   bool check_desugar_deps;
   bool multi_release;
+  std::string hermetic_java_home;
 
  protected:
   /*

src/tools/singlejar/options_test.cc

@@ -20,11 +20,10 @@
 #include "googletest/include/gtest/gtest.h"
 
 TEST(OptionsTest, Flags1) {
-  const char *args[] = {"--exclude_build_data",
-                        "--compression",
-                        "--normalize",
-                        "--no_duplicates",
-                        "--output", "output_jar"};
+  const char *args[] = {
+      "--exclude_build_data", "--compression",     "--normalize",
+      "--no_duplicates",      "--output",          "output_jar",
+      "--hermetic_java_home", "hermetic_java_home"};
   Options options;
   options.ParseCommandLine(arraysize(args), args);
 
@@ -38,6 +37,7 @@ TEST(OptionsTest, Flags1) {
   EXPECT_FALSE(options.check_desugar_deps);
   EXPECT_FALSE(options.multi_release);
   EXPECT_EQ("output_jar", options.output_jar);
+  EXPECT_EQ("hermetic_java_home", options.hermetic_java_home);
 }
 
 TEST(OptionsTest, Flags2) {
@@ -60,6 +60,7 @@ TEST(OptionsTest, Flags2) {
   ASSERT_TRUE(options.warn_duplicate_resources);
   ASSERT_TRUE(options.check_desugar_deps);
   ASSERT_TRUE(options.multi_release);
+  EXPECT_EQ("", options.hermetic_java_home);
 }
 
 TEST(OptionsTest, SingleOptargs) {

src/tools/singlejar/output_jar.cc

@@ -145,6 +145,9 @@ int OutputJar::Doit(Options *options) {
   if (options_->multi_release) {
     manifest_.EnableMultiRelease();
   }
+  if (!options_->hermetic_java_home.empty()) {
+    manifest_.AppendLine("Hermetic-Java-Home: " + options_->hermetic_java_home);
+  }
   for (auto &manifest_line : options_->manifest_lines) {
     if (!manifest_line.empty()) {
       manifest_.AppendLine(manifest_line);

src/tools/singlejar/output_jar_simple_test.cc

@@ -989,4 +989,17 @@ TEST_F(OutputJarSimpleTest, MultiReleaseManifestLines) {
       manifest);
 }
 
+// --hermetic_java_home
+TEST_F(OutputJarSimpleTest, HermeticJavaHome) {
+  string out_path = OutputFilePath("out.jar");
+  CreateOutput(out_path, {"--hermetic_java_home", "foo/bar/java_home"});
+  string manifest = GetEntryContents(out_path, "META-INF/MANIFEST.MF");
+  EXPECT_EQ(
+      "Manifest-Version: 1.0\r\n"
+      "Created-By: singlejar\r\n"
+      "Hermetic-Java-Home: foo/bar/java_home\r\n"
+      "\r\n",
+      manifest);
+}
+
 }  // namespace