Refactor backported_fixes rules to share with cts

The sharable rules include

proto libary and file
Combining BackportedFix files
Converting BockportedFix text protos to binary protos

Test: atest backported_fixes_main_lib_test backported_fixes_common_test
Bug: 375460641
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:13a26b80a4250ff54bc6364ea01e1b9ede8558f5)
Merged-In: Ie75ede120d5555119ad265e4def728af9535bb1f
Change-Id: Ie75ede120d5555119ad265e4def728af9535bb1f
diff --git a/backported_fixes/Android.bp b/backported_fixes/Android.bp
index a20f3fc..243e77e 100644
--- a/backported_fixes/Android.bp
+++ b/backported_fixes/Android.bp
@@ -19,19 +19,24 @@
 
 genrule {
     name: "applied_backported_fixes",
-    tools: ["applied_backported_fixes_main"],
+    tools: ["applied_backported_fixes_property_writer"],
     srcs: [":applied_backported_fix_binpbs"],
     out: ["applied_backported_fixes.prop"],
-    cmd: "$(location applied_backported_fixes_main)" +
+    cmd: "$(location applied_backported_fixes_property_writer)" +
         " -p $(location applied_backported_fixes.prop)" +
         " $(in)",
 }
 
-java_library {
-    name: "backported_fixes_proto",
+filegroup {
+    name: "backported_fixes_proto_file",
     srcs: [
         "backported_fixes.proto",
     ],
+}
+
+java_library {
+    name: "backported_fixes_proto",
+    srcs: ["backported_fixes.proto"],
     host_supported: true,
 }
 
@@ -63,7 +68,7 @@
 }
 
 java_library {
-    name: "applied_backported_fixes_lib",
+    name: "backported_fixes_main_lib",
     srcs: ["src/java/com/android/build/backportedfixes/*.java"],
     static_libs: [
         "backported_fixes_common",
@@ -75,18 +80,35 @@
 }
 
 java_binary_host {
-    name: "applied_backported_fixes_main",
-    main_class: "com.android.build.backportedfixes.Main",
+    name: "applied_backported_fixes_property_writer",
+    main_class: "com.android.build.backportedfixes.WriteBackportedFixesPropFile",
     static_libs: [
-        "applied_backported_fixes_lib",
+        "backported_fixes_main_lib",
     ],
 }
 
+java_binary_host {
+    name: "backported_fixes_combiner",
+    main_class: "com.android.build.backportedfixes.CombineBackportedFixes",
+    static_libs: [
+        "backported_fixes_main_lib",
+    ],
+}
+
+// Combines BackportedFix binary proto files into a single BackportedFixes binary proto file.
+genrule_defaults {
+    name: "default_backported_fixes_combiner",
+    tools: ["backported_fixes_combiner"],
+    cmd: "$(location backported_fixes_combiner)" +
+        " -o $(out)" +
+        " $(in)",
+}
+
 java_test_host {
-    name: "applied_backported_fixes_test",
+    name: "backported_fixes_main_lib_test",
     srcs: ["tests/java/com/android/build/backportedfixes/*.java"],
     static_libs: [
-        "applied_backported_fixes_lib",
+        "backported_fixes_main_lib",
         "backported_fixes_proto",
         "junit",
         "truth",
@@ -97,19 +119,25 @@
     test_suites: ["general-tests"],
 }
 
+// Converts BackprotedFix text protos to binary protos
+genrule_defaults {
+    name: "default_backported_fix_binpbs",
+    tools: ["aprotoc"],
+    tool_files: [
+        ":backported_fixes_proto_file",
+    ],
+    cmd: "$(location aprotoc)  " +
+        " --encode=com.android.build.backportedfixes.BackportedFix" +
+        "  $(location :backported_fixes_proto_file)" +
+        " < $(in)" +
+        " > $(out); echo $(out)",
+}
+
 gensrcs {
     name: "applied_backported_fix_binpbs",
-    tools: ["aprotoc"],
+    defaults: ["default_backported_fix_binpbs"],
+    output_extension: "binpb",
     srcs: [
         "applied_fixes/*.txtpb",
     ],
-    tool_files: [
-        "backported_fixes.proto",
-    ],
-    output_extension: "binpb",
-    cmd: "$(location aprotoc)  " +
-        " --encode=com.android.build.backportedfixes.BackportedFix" +
-        "  $(location backported_fixes.proto)" +
-        " < $(in)" +
-        " > $(out); echo $(out)",
 }
diff --git a/backported_fixes/src/java/com/android/build/backportedfixes/CombineBackportedFixes.java b/backported_fixes/src/java/com/android/build/backportedfixes/CombineBackportedFixes.java
new file mode 100644
index 0000000..0592cc1
--- /dev/null
+++ b/backported_fixes/src/java/com/android/build/backportedfixes/CombineBackportedFixes.java
@@ -0,0 +1,65 @@
+
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * 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 com.android.build.backportedfixes;
+
+import com.android.build.backportedfixes.common.Parser;
+
+import com.beust.jcommander.JCommander;
+import com.beust.jcommander.Parameter;
+import com.beust.jcommander.converters.FileConverter;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.List;
+
+
+/** Creates a BackportedFixes binary proto file from a list of BackportedFix proto binary files. */
+public final class CombineBackportedFixes {
+
+    @Parameter(description = "BackportedFix proto binary files",
+            converter = FileConverter.class,
+            required = true)
+    List<File> fixFiles;
+    @Parameter(description = "Write the BackportedFixes proto binary to this file",
+            names = {"--out","-o"},
+            converter = FileConverter.class,
+            required = true)
+    File outFile;
+
+    public static void main(String... argv) throws Exception {
+        CombineBackportedFixes main = new CombineBackportedFixes();
+        JCommander.newBuilder().addObject(main).build().parse(argv);
+        main.run();
+    }
+
+    CombineBackportedFixes() {
+    }
+
+    private void run() throws Exception {
+        try (var out = new FileOutputStream(outFile)) {
+            var fixes = Parser.parseBackportedFixFiles(fixFiles);
+            writeBackportedFixes(fixes, out);
+        }
+    }
+
+    static void writeBackportedFixes(BackportedFixes fixes, OutputStream out)
+            throws IOException {
+        fixes.writeTo(out);
+    }
+}
diff --git a/backported_fixes/src/java/com/android/build/backportedfixes/Main.java b/backported_fixes/src/java/com/android/build/backportedfixes/WriteBackportedFixesPropFile.java
similarity index 74%
rename from backported_fixes/src/java/com/android/build/backportedfixes/Main.java
rename to backported_fixes/src/java/com/android/build/backportedfixes/WriteBackportedFixesPropFile.java
index 79148cc..0ffb4ac 100644
--- a/backported_fixes/src/java/com/android/build/backportedfixes/Main.java
+++ b/backported_fixes/src/java/com/android/build/backportedfixes/WriteBackportedFixesPropFile.java
@@ -18,7 +18,6 @@
 
 import static java.nio.charset.StandardCharsets.UTF_8;
 
-import com.android.build.backportedfixes.common.ClosableCollection;
 import com.android.build.backportedfixes.common.Parser;
 
 import com.beust.jcommander.JCommander;
@@ -33,27 +32,38 @@
 import java.util.List;
 import java.util.stream.Collectors;
 
-public final class Main {
-    @Parameter(description = "BackportedFix proto binary files", converter = FileConverter.class,
+
+/**
+ * Creates backported fix properties file.
+ *
+ * <p>Writes BitSet of backported fix aliases from a list of BackportedFix proto binary files and
+ * writes the property {@value PROPERTY_NAME} to a file.
+ */
+public final class WriteBackportedFixesPropFile {
+
+    private static final String PROPERTY_NAME = "ro.build.backported_fixes.alias_bitset.long_list";
+    @Parameter(description = "BackportedFix proto binary files",
+            converter = FileConverter.class,
             required = true)
     List<File> fixFiles;
     @Parameter(description = "The file to write the property value to.",
-            names = {"--property_file", "-p"}, converter = FileConverter.class, required = true)
+            names = {"--property_file", "-p"},
+            converter = FileConverter.class,
+            required = true)
     File propertyFile;
 
     public static void main(String... argv) throws Exception {
-        Main main = new Main();
+        WriteBackportedFixesPropFile main = new WriteBackportedFixesPropFile();
         JCommander.newBuilder().addObject(main).build().parse(argv);
         main.run();
     }
 
-    Main() {
+    WriteBackportedFixesPropFile() {
     }
 
     private void run() throws Exception {
-        try (var fixStreams = ClosableCollection.wrap(Parser.getFileInputStreams(fixFiles));
-             var out = Files.newWriter(propertyFile, UTF_8)) {
-            var fixes = Parser.parseBackportedFixes(fixStreams.getCollection());
+        try (var out = Files.newWriter(propertyFile, UTF_8)) {
+            var fixes = Parser.parseBackportedFixFiles(fixFiles);
             writeFixesAsAliasBitSet(fixes, out);
         }
     }
@@ -70,7 +80,7 @@
                 fixes.getFixesList().stream().mapToInt(BackportedFix::getAlias).toArray());
         String bsString = Arrays.stream(bsArray).mapToObj(Long::toString).collect(
                 Collectors.joining(","));
-        printWriter.printf("ro.build.backported_fixes.alias_bitset.long_list=%s", bsString);
+        printWriter.printf("%s=%s", PROPERTY_NAME, bsString);
         printWriter.println();
         if (printWriter.checkError()) {
             throw new RuntimeException("There was an error writing to " + out.toString());
diff --git a/backported_fixes/src/java/com/android/build/backportedfixes/common/ClosableCollection.java b/backported_fixes/src/java/com/android/build/backportedfixes/common/ClosableCollection.java
deleted file mode 100644
index 75b6730..0000000
--- a/backported_fixes/src/java/com/android/build/backportedfixes/common/ClosableCollection.java
+++ /dev/null
@@ -1,67 +0,0 @@
-/*
- * Copyright (C) 2024 The Android Open Source Project
- *
- * 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 com.android.build.backportedfixes.common;
-
-import com.google.common.collect.ImmutableList;
-
-import java.util.ArrayList;
-import java.util.Collection;
-
-/** An AutoCloseable holder for a collection of AutoCloseables. */
-public final class ClosableCollection<T extends AutoCloseable, C extends Collection<T>> implements
-        AutoCloseable {
-    C source;
-
-    /** Makes the collection AutoCloseable. */
-    public static <T extends AutoCloseable, C extends Collection<T>> ClosableCollection<T, C> wrap(
-            C source) {
-        return new ClosableCollection<>(source);
-    }
-
-    private ClosableCollection(C source) {
-        this.source = source;
-    }
-
-    /** Get the source collection. */
-    public C getCollection() {
-        return source;
-    }
-
-    /**
-     * Closes each item in the collection.
-     *
-     * @throws Exception if any close throws an an exception, a new exception is thrown with
-     *                   all the exceptions thrown closing the streams added as a suppressed
-     *                   exceptions.
-     */
-    @Override
-    public void close() throws Exception {
-        var failures = new ArrayList<Exception>();
-        for (T t : source) {
-            try {
-                t.close();
-            } catch (Exception e) {
-                failures.add(e);
-            }
-        }
-        if (!failures.isEmpty()) {
-            Exception e = new Exception(
-                    "%d of %d failed while closing".formatted(failures.size(), source.size()));
-            failures.forEach(e::addSuppressed);
-            throw e;
-        }
-    }
-}
diff --git a/backported_fixes/src/java/com/android/build/backportedfixes/common/Parser.java b/backported_fixes/src/java/com/android/build/backportedfixes/common/Parser.java
index 6b08b8f..6180fdc 100644
--- a/backported_fixes/src/java/com/android/build/backportedfixes/common/Parser.java
+++ b/backported_fixes/src/java/com/android/build/backportedfixes/common/Parser.java
@@ -15,9 +15,12 @@
  */
 package com.android.build.backportedfixes.common;
 
+import static com.google.common.base.Preconditions.checkNotNull;
+
 import com.android.build.backportedfixes.BackportedFix;
 import com.android.build.backportedfixes.BackportedFixes;
 
+import com.google.common.base.Throwables;
 import com.google.common.collect.ImmutableList;
 
 import java.io.File;
@@ -26,7 +29,10 @@
 import java.io.IOException;
 import java.io.InputStream;
 import java.util.BitSet;
+import java.util.Comparator;
 import java.util.List;
+import java.util.stream.Collector;
+import java.util.stream.Collectors;
 
 
 /** Static utilities for working with {@link BackportedFixes}. */
@@ -54,16 +60,79 @@
     /**
      * Creates a {@link BackportedFixes} from a list of {@link BackportedFix} binary proto streams.
      */
-    public static BackportedFixes parseBackportedFixes(List<? extends InputStream> fixStreams)
-            throws
-            IOException {
-        var fixes = BackportedFixes.newBuilder();
-        for (var s : fixStreams) {
-            BackportedFix fix = BackportedFix.parseFrom(s);
-            fixes.addFixes(fix);
-            s.close();
+    public static BackportedFixes parseBackportedFixFiles(List<File> fixFiles)
+            throws IOException {
+        try {
+            return fixFiles.stream().map(Parser::tunelFileInputStream)
+                    .map(Parser::tunnelParse)
+                    .sorted(Comparator.comparing(BackportedFix::getKnownIssue))
+                    .collect(fixCollector());
+
+        } catch (TunnelException e) {
+            throw e.rethrow(FileNotFoundException.class, IOException.class);
         }
-        return fixes.build();
+    }
+
+
+    private static Collector<BackportedFix, ?, BackportedFixes> fixCollector() {
+        return Collectors.collectingAndThen(Collectors.toList(), fixList -> {
+            var result = BackportedFixes.newBuilder();
+            result.addAllFixes(fixList);
+            return result.build();
+        });
+    }
+
+    private static FileInputStream tunelFileInputStream(File file) throws TunnelException {
+        try {
+            return new FileInputStream(file);
+        } catch (FileNotFoundException e) {
+            throw new TunnelException(e);
+        }
+    }
+
+    private static BackportedFix tunnelParse(InputStream s) throws TunnelException {
+        try {
+            var fix = BackportedFix.parseFrom(s);
+            s.close();
+            return fix;
+        } catch (IOException e) {
+            throw new TunnelException(e);
+        }
+    }
+
+    private static class TunnelException extends RuntimeException {
+        TunnelException(Exception cause) {
+            super("If you see this TunnelException something went wrong.  It should always be rethrown as the cause.", cause);
+        }
+
+        <X extends Exception> RuntimeException rethrow(Class<X> exceptionClazz) throws X {
+            checkNotNull(exceptionClazz);
+            Throwables.throwIfInstanceOf(getCause(), exceptionClazz);
+            throw exception(
+                    getCause(),
+                    "rethrow(%s) doesn't match underlying exception", exceptionClazz);
+        }
+
+        public <X1 extends Exception, X2 extends Exception> RuntimeException rethrow(
+                Class<X1> exceptionClazz1, Class<X2> exceptionClazz2) throws X1, X2 {
+            checkNotNull(exceptionClazz1);
+            checkNotNull(exceptionClazz2);
+            Throwables.throwIfInstanceOf(getCause(), exceptionClazz1);
+            Throwables.throwIfInstanceOf(getCause(), exceptionClazz2);
+            throw exception(
+                    getCause(),
+                    "rethrow(%s, %s) doesn't match underlying exception",
+                    exceptionClazz1,
+                    exceptionClazz2);
+        }
+
+        private static ClassCastException exception(
+                Throwable cause, String message, Object... formatArgs) {
+            ClassCastException result = new ClassCastException(String.format(message, formatArgs));
+            result.initCause(cause);
+            return result;
+        }
+
     }
 
     private Parser() {
diff --git a/backported_fixes/tests/java/com/android/build/backportedfixes/CombineBackportedFixesTest.java b/backported_fixes/tests/java/com/android/build/backportedfixes/CombineBackportedFixesTest.java
new file mode 100644
index 0000000..21d5f1e
--- /dev/null
+++ b/backported_fixes/tests/java/com/android/build/backportedfixes/CombineBackportedFixesTest.java
@@ -0,0 +1,41 @@
+
+/*
+ * Copyright (C) 2024 The Android Open Source Project
+ *
+ * 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 com.android.build.backportedfixes;
+
+import com.google.common.truth.Truth;
+
+import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+/** Tests for {@link CombineBackportedFixes}. */
+public class CombineBackportedFixesTest {
+
+
+    @Test
+    public void writeBackportedFixes_default() throws IOException {
+        // Not much of a test, but there is not much to test.
+        BackportedFixes fixes = BackportedFixes.newBuilder()
+                .addFixes(BackportedFix.newBuilder().setKnownIssue(123).build())
+                .build();
+        var result = new ByteArrayOutputStream();
+        CombineBackportedFixes.writeBackportedFixes(fixes, result);
+        Truth.assertThat(BackportedFixes.parseFrom(result.toByteArray()))
+                .isEqualTo(fixes);
+    }
+}
diff --git a/backported_fixes/tests/java/com/android/build/backportedfixes/MainTest.java b/backported_fixes/tests/java/com/android/build/backportedfixes/WriteBackportedFixesPropFileTest.java
similarity index 87%
rename from backported_fixes/tests/java/com/android/build/backportedfixes/MainTest.java
rename to backported_fixes/tests/java/com/android/build/backportedfixes/WriteBackportedFixesPropFileTest.java
index 84061e1..3209c15 100644
--- a/backported_fixes/tests/java/com/android/build/backportedfixes/MainTest.java
+++ b/backported_fixes/tests/java/com/android/build/backportedfixes/WriteBackportedFixesPropFileTest.java
@@ -23,8 +23,8 @@
 import java.io.PrintWriter;
 import java.io.StringWriter;
 
-/** Tests for {@link Main}. */
-public class MainTest {
+/** Tests for {@link WriteBackportedFixesPropFile}. */
+public class WriteBackportedFixesPropFileTest {
 
 
     @Test
@@ -32,7 +32,7 @@
         BackportedFixes fixes = BackportedFixes.newBuilder().build();
         var result = new StringWriter();
 
-        Main.writeFixesAsAliasBitSet(fixes, new PrintWriter(result));
+        WriteBackportedFixesPropFile.writeFixesAsAliasBitSet(fixes, new PrintWriter(result));
 
         Truth.assertThat(result.toString())
                 .isEqualTo("""
@@ -50,7 +50,7 @@
                 .build();
         var result = new StringWriter();
 
-        Main.writeFixesAsAliasBitSet(fixes, new PrintWriter(result));
+        WriteBackportedFixesPropFile.writeFixesAsAliasBitSet(fixes, new PrintWriter(result));
 
         Truth.assertThat(result.toString())
                 .isEqualTo("""
diff --git a/backported_fixes/tests/java/com/android/build/backportedfixes/common/CloseableCollectionTest.java b/backported_fixes/tests/java/com/android/build/backportedfixes/common/CloseableCollectionTest.java
deleted file mode 100644
index d3d84a8..0000000
--- a/backported_fixes/tests/java/com/android/build/backportedfixes/common/CloseableCollectionTest.java
+++ /dev/null
@@ -1,91 +0,0 @@
-/*
- * Copyright (C) 2024 The Android Open Source Project
- *
- * 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 com.android.build.backportedfixes.common;
-
-import com.google.common.collect.ImmutableSet;
-import com.google.common.truth.Correspondence;
-import com.google.common.truth.Truth;
-
-import org.junit.Test;
-
-/** Tests for {@link ClosableCollection}. */
-public class CloseableCollectionTest {
-
-    private static class FakeCloseable implements AutoCloseable {
-        private final boolean throwOnClose;
-        private final String name;
-
-
-        private boolean isClosed = false;
-
-        private FakeCloseable(String name, boolean throwOnClose) {
-            this.name = name;
-            this.throwOnClose = throwOnClose;
-
-        }
-
-        private static FakeCloseable named(String name) {
-            return new FakeCloseable(name, false);
-        }
-
-        private static FakeCloseable failing(String name) {
-            return new FakeCloseable(name, true);
-        }
-
-        public boolean isClosed() {
-            return isClosed;
-        }
-
-        @Override
-        public void close() throws Exception {
-            if (throwOnClose) {
-                throw new Exception(name + " close failed");
-            }
-            isClosed = true;
-        }
-    }
-
-
-    @Test
-    public void bothClosed() throws Exception {
-        var c = ImmutableSet.of(FakeCloseable.named("foo"), FakeCloseable.named("bar"));
-        try (var cc = ClosableCollection.wrap(c);) {
-            Truth.assertThat(cc.getCollection()).isSameInstanceAs(c);
-        }
-        Truth.assertThat(c)
-                .comparingElementsUsing(
-                        Correspondence.transforming(FakeCloseable::isClosed, "is closed"))
-                .containsExactly(true, true);
-    }
-
-    @Test
-    public void bothFailed() {
-        var c = ImmutableSet.of(FakeCloseable.failing("foo"), FakeCloseable.failing("bar"));
-
-        try {
-            try (var cc = ClosableCollection.wrap(c);) {
-                Truth.assertThat(cc.getCollection()).isSameInstanceAs(c);
-            }
-        } catch (Exception e) {
-            Truth.assertThat(e).hasMessageThat().isEqualTo("2 of 2 failed while closing");
-            Truth.assertThat(e.getSuppressed())
-                    .asList()
-                    .comparingElementsUsing(
-                            Correspondence.transforming(Exception::getMessage, "has a message of "))
-                    .containsExactly("foo close failed", "bar close failed");
-        }
-    }
-}
diff --git a/backported_fixes/tests/java/com/android/build/backportedfixes/common/ParserTest.java b/backported_fixes/tests/java/com/android/build/backportedfixes/common/ParserTest.java
index 444e694..57a0a40 100644
--- a/backported_fixes/tests/java/com/android/build/backportedfixes/common/ParserTest.java
+++ b/backported_fixes/tests/java/com/android/build/backportedfixes/common/ParserTest.java
@@ -23,15 +23,21 @@
 
 import com.google.common.collect.ImmutableList;
 
+import org.junit.Rule;
 import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
 
-import java.io.ByteArrayInputStream;
+import java.io.File;
+import java.io.FileOutputStream;
 import java.io.IOException;
 import java.nio.file.Files;
 
 /** Tests for {@link Parser}.*/
 public class ParserTest {
 
+    @Rule
+    public TemporaryFolder mTempFolder = new TemporaryFolder();
+
     @Test
     public void getFileInputStreams() throws IOException {
         var results = Parser.getFileInputStreams(
@@ -53,15 +59,15 @@
     }
 
     @Test
-    public void parseBackportedFixes_empty() throws IOException {
-        var result = Parser.parseBackportedFixes(ImmutableList.of());
+    public void parseBackportedFixFiles_empty() throws IOException {
+        var result = Parser.parseBackportedFixFiles(ImmutableList.of());
         assertThat(result).isEqualTo(BackportedFixes.getDefaultInstance());
     }
 
+
     @Test
-    public void parseBackportedFixes_oneBlank() throws IOException {
-        var result = Parser.parseBackportedFixes(
-                ImmutableList.of(inputStream(BackportedFix.getDefaultInstance())));
+    public void parseBackportedFixFiles_oneBlank() throws IOException {
+        var result = Parser.parseBackportedFixFiles(ImmutableList.of(mTempFolder.newFile()));
 
         assertThat(result).isEqualTo(
                 BackportedFixes.newBuilder()
@@ -70,7 +76,7 @@
     }
 
     @Test
-    public void parseBackportedFixes_two() throws IOException {
+    public void parseBackportedFixFiles_two() throws IOException {
         BackportedFix ki123 = BackportedFix.newBuilder()
                 .setKnownIssue(123)
                 .setAlias(1)
@@ -79,8 +85,8 @@
                 .setKnownIssue(456)
                 .setAlias(2)
                 .build();
-        var result = Parser.parseBackportedFixes(
-                ImmutableList.of(inputStream(ki123), inputStream(ki456)));
+        var result = Parser.parseBackportedFixFiles(
+                ImmutableList.of(tempFile(ki456), tempFile(ki123)));
         assertThat(result).isEqualTo(
                 BackportedFixes.newBuilder()
                         .addFixes(ki123)
@@ -88,7 +94,11 @@
                         .build());
     }
 
-    private static ByteArrayInputStream inputStream(BackportedFix f) {
-        return new ByteArrayInputStream(f.toByteArray());
+    private File tempFile(BackportedFix fix) throws IOException {
+        File f = mTempFolder.newFile();
+        try (FileOutputStream out = new FileOutputStream(f)) {
+            fix.writeTo(out);
+            return f;
+        }
     }
 }