Trigger a full rebuild when classpath is modified

- A full rebuild is needed when a file contained inside a folder
in the classpath or an archive in the classpath is more recent
than the generated dex file.

Change-Id: Iec0c3e0d2d0150f2ba02ca51fbec0913607df07a

4 files changed, 149 insertions, 5 deletions

diff --git a/jack/src/com/android/jack/experimental/incremental/JackIncremental.java b/jack/src/com/android/jack/experimental/incremental/JackIncremental.java
index 344f4e1..93ad0fc 100644
--- a/jack/src/com/android/jack/experimental/incremental/JackIncremental.java
+++ b/jack/src/com/android/jack/experimental/incremental/JackIncremental.java
@@ -184,7 +184,7 @@ public class JackIncremental extends CommandLine {
 
     compilerState = new CompilerState(incrementalFolder);
 
-    if (isIncrementalCompilation(options)) {
+    if (isIncrementalCompilation(options) && !needFullRebuild(options)) {
       logger.log(Level.INFO, "Incremental compilation");
 
       List<String> javaFilesNames = getJavaFilesSpecifiedOnCommandLine(options);
@@ -262,6 +262,54 @@ public class JackIncremental extends CommandLine {
     return compilerState;
   }
 
+  /*
+   * A full rebuild is needed when a file contained inside a folder in the classpath
+   * or an archive in the classpath is more recent than the generated dex file.
+   */
+  private static boolean needFullRebuild(@Nonnull Options options) {
+    File outputDexFile = new File(options.getOutputDir(), DexFileWriter.DEX_FILENAME);
+    if (outputDexFile.exists()) {
+      for (File lib : options.getBootclasspath()) {
+        if (isModifiedLibrary(lib, outputDexFile.lastModified())) {
+          return true;
+        }
+      }
+      for (File lib : options.getClasspath()) {
+        if (isModifiedLibrary(lib, outputDexFile.lastModified())) {
+          return true;
+        }
+      }
+    }
+    return false;
+  }
+
+  private static boolean isModifiedLibrary(@Nonnull File lib, long time) {
+    if (lib.isFile() && (lib.lastModified() > time)) {
+      return true;
+    } else if (lib.isDirectory() && hasModifiedFile(lib, time)) {
+      return true;
+    }
+
+    return false;
+  }
+
+  private static boolean hasModifiedFile(@Nonnull File file, long time) {
+    assert file.isDirectory();
+
+    for (File f : file.listFiles()) {
+      if (f.isDirectory()) {
+        if (hasModifiedFile(f, time)) {
+          return true;
+        }
+      } else if (f.lastModified() > time) {
+          return true;
+      }
+    }
+
+    return false;
+  }
+
+  @Nonnull
   private static String dependenciesToString(@Nonnull Map<String, Set<String>> fileDependencies) {
     StringBuilder builder = new StringBuilder();
     builder.append(TextUtils.LINE_SEPARATOR);
@@ -485,8 +533,7 @@ public class JackIncremental extends CommandLine {
   }
 
   private static boolean isIncrementalCompilation(@Nonnull Options options) {
-    if (!options.getEcjArguments().isEmpty()
-        && getCompilerState().exists()) {
+    if (!options.getEcjArguments().isEmpty() && getCompilerState().exists()) {
       return true;
     }
 
diff --git a/jack/tests/com/android/jack/experimental/incremental/DependenciesTest015.java b/jack/tests/com/android/jack/experimental/incremental/DependenciesTest015.java
new file mode 100644
index 0000000..c4291d2
--- /dev/null
+++ b/jack/tests/com/android/jack/experimental/incremental/DependenciesTest015.java
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2014 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.jack.experimental.incremental;
+
+import com.android.jack.Main;
+import com.android.jack.TestTools;
+import com.android.jack.frontend.FrontendCompilationException;
+
+import junit.framework.Assert;
+
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.io.File;
+import java.util.List;
+
+/**
+ * JUnit test checking incremental support.
+ */
+public class DependenciesTest015 {
+
+  @BeforeClass
+  public static void setUpClass() {
+    Main.class.getClassLoader().setDefaultAssertionStatus(true);
+  }
+
+  /**
+   * Check that incremental compilation works when library on classpath is modified.
+   */
+  @Test
+  public void testDependency001() throws Exception {
+    IncrementalTestingEnvironment iteLib =
+        new IncrementalTestingEnvironment(TestTools.createTempDir("DependenciesTest_", "_001_lib"));
+
+    iteLib.addJavaFile("jack.incremental", "A.java", "package jack.incremental; \n"
+        + "public abstract class A { \n" + "public abstract void m(); }");
+
+    iteLib.incrementalBuildFromFolder();
+    iteLib.snapshotJackFilesModificationDate();
+    List<File> jackFilesLib = iteLib.getJackFiles();
+    Assert.assertEquals(1, jackFilesLib.size());
+
+
+    IncrementalTestingEnvironment iteProg =
+        new IncrementalTestingEnvironment(TestTools.createTempDir("DependenciesTest_", "_001_prog"));
+
+    iteProg.addJavaFile("jack.incremental", "B.java", "package jack.incremental; \n"
+        + "public class B extends A { \n" + " @Override public void m(){} }");
+
+    iteProg.incrementalBuildFromFolder(new File[]{iteLib.getJackFolder()});
+    iteProg.snapshotJackFilesModificationDate();
+    Assert.assertEquals(1, iteProg.getJackFiles().size());
+
+    iteLib.deleteJavaFile("jack.incremental", "A.java");
+    iteLib.addJavaFile("jack.incremental", "A.java", "package jack.incremental; \n"
+        + "public abstract class A { \n" + "public abstract int m(); }");
+    iteLib.incrementalBuildFromFolder();
+    iteLib.snapshotJackFilesModificationDate();
+    jackFilesLib = iteLib.getJackFiles();
+    Assert.assertEquals(1, jackFilesLib.size());
+
+    try {
+      iteProg.incrementalBuildFromFolder(new File[] {iteLib.getJackFolder()});
+      Assert.fail();
+    } catch (FrontendCompilationException e) {
+      Assert.assertTrue(iteProg.getStringRepresentingErr().contains(
+          "The return type is incompatible with A.m()"));
+    }
+  }
+}
+
diff --git a/jack/tests/com/android/jack/experimental/incremental/DependencyAllTests.java b/jack/tests/com/android/jack/experimental/incremental/DependencyAllTests.java
index 458b6b5..e8b42a8 100644
--- a/jack/tests/com/android/jack/experimental/incremental/DependencyAllTests.java
+++ b/jack/tests/com/android/jack/experimental/incremental/DependencyAllTests.java
@@ -9,6 +9,7 @@ import org.junit.runners.Suite.SuiteClasses;
     DependenciesTest003.class, DependenciesTest004.class, DependenciesTest005.class,
     DependenciesTest006.class, DependenciesTest007.class, DependenciesTest008.class,
     DependenciesTest009.class, DependenciesTest010.class, DependenciesTest011.class,
-    DependenciesTest012.class, DependenciesTest013.class, DependenciesTest014.class})
+    DependenciesTest012.class, DependenciesTest013.class, DependenciesTest014.class,
+    DependenciesTest015.class})
 public class DependencyAllTests {
 }
\ No newline at end of file
diff --git a/jack/tests/com/android/jack/experimental/incremental/IncrementalTestingEnvironment.java b/jack/tests/com/android/jack/experimental/incremental/IncrementalTestingEnvironment.java
index a7b3d8e..099425d 100644
--- a/jack/tests/com/android/jack/experimental/incremental/IncrementalTestingEnvironment.java
+++ b/jack/tests/com/android/jack/experimental/incremental/IncrementalTestingEnvironment.java
@@ -129,6 +129,10 @@ public class IncrementalTestingEnvironment extends TestTools {
   }
 
   public void incrementalBuildFromFolder() throws Exception {
+    incrementalBuildFromFolder(null);
+  }
+
+  public void incrementalBuildFromFolder(@CheckForNull File[] classpath) throws Exception {
     startOutRedirection();
     startErrRedirection();
 
@@ -136,7 +140,9 @@ public class IncrementalTestingEnvironment extends TestTools {
     options.setIncrementalFolder(getCompilerStateFolder());
 
     compileSourceToDex(options, sourceFolder,
-        TestTools.getClasspathAsString(TestTools.getDefaultBootclasspath()), testingFolder);
+        classpath == null ? TestTools.getClasspathAsString(TestTools.getDefaultBootclasspath())
+            : TestTools.getClasspathsAsString(TestTools.getDefaultBootclasspath(), classpath),
+        testingFolder);
 
     Thread.sleep(1000);
 
@@ -215,6 +221,11 @@ public class IncrementalTestingEnvironment extends TestTools {
   }
 
   @Nonnull
+  public File getJackFolder() {
+    return jackFolder;
+  }
+
+  @Nonnull
   public List<File> getJackFiles() {
     List<File> jackFiles = new ArrayList<File>();
     fillJackFiles(jackFolder, jackFiles);