Don't report unused resources in projects with errors

If a project contains errors in the source code, lint won't be able to
parse the source code, and in that case it might draw the wrong
conclusions about unused resources.

This can also happen if there's an actual bug in the Java parser,
which is sometimes the case; see for example
http://code.google.com/p/projectlombok/issues/detail?id=415
http://code.google.com/p/projectlombok/issues/detail?id=311

In both cases, when we encounter a failure to parse a Java file, we
record the fact that not all Java files were properly processed, and
rules, such as the UnusedResource detector, can (and now does) use
this to for example skip reporting unused resources in this case since
it is operating with incomplete data.

Change-Id: I00991c10d05965ce151fb0dd322f32229dcd12cd

5 files changed, 48 insertions, 2 deletions

diff --git a/lint/cli/src/com/android/tools/lint/LombokParser.java b/lint/cli/src/com/android/tools/lint/LombokParser.java
index 2c263c6..bc841e2 100644
--- a/lint/cli/src/com/android/tools/lint/LombokParser.java
+++ b/lint/cli/src/com/android/tools/lint/LombokParser.java
@@ -48,6 +48,8 @@ public class LombokParser implements IJavaParser {
             // Don't analyze files containing errors
             List<ParseProblem> problems = source.getProblems();
             if (problems != null && problems.size() > 0) {
+                context.getDriver().setHasParserErrors(true);
+
                 /* Silently ignore the errors. There are still some bugs in Lombok/Parboiled
                  * (triggered if you run lint on the AOSP framework directory for example),
                  * and having these show up as fatal errors when it's really a tool bug
@@ -61,7 +63,7 @@ public class LombokParser implements IJavaParser {
                     // See http://code.google.com/p/projectlombok/issues/detail?id=313
                     String message = problem.getMessage();
                     context.report(
-                            IssueRegistry.PARSER_ERROR, location,
+                            com.android.tools.lint.client.api.IssueRegistry.PARSER_ERROR, location,
                             message,
                             null);
 
diff --git a/lint/libs/lint_api/src/com/android/tools/lint/client/api/LintDriver.java b/lint/libs/lint_api/src/com/android/tools/lint/client/api/LintDriver.java
index 352fd1d..068bf2a 100644
--- a/lint/libs/lint_api/src/com/android/tools/lint/client/api/LintDriver.java
+++ b/lint/libs/lint_api/src/com/android/tools/lint/client/api/LintDriver.java
@@ -129,6 +129,7 @@ public class LintDriver {
     private Project[] mCurrentProjects;
     private Project mCurrentProject;
     private boolean mAbbreviating = true;
+    private boolean mParserErrors;
 
     /**
      * Creates a new {@link LintDriver}
@@ -230,6 +231,30 @@ public class LintDriver {
     }
 
     /**
+     * Returns whether lint has encountered any files with fatal parser errors
+     * (e.g. broken source code, or even broken parsers)
+     * <p>
+     * This is useful for checks that need to make sure they've seen all data in
+     * order to be conclusive (such as an unused resource check).
+     *
+     * @return true if any files were not properly processed because they
+     *         contained parser errors
+     */
+    public boolean hasParserErrors() {
+        return mParserErrors;
+    }
+
+    /**
+     * Sets whether lint has encountered files with fatal parser errors.
+     *
+     * @see #hasParserErrors()
+     * @param hasErrors whether parser errors have been encountered
+     */
+    public void setHasParserErrors(boolean hasErrors) {
+        mParserErrors = hasErrors;
+    }
+
+    /**
      * Returns the projects being analyzed
      *
      * @return the projects being analyzed
diff --git a/lint/libs/lint_checks/src/com/android/tools/lint/checks/UnusedResourceDetector.java b/lint/libs/lint_checks/src/com/android/tools/lint/checks/UnusedResourceDetector.java
index bcbdd85..3217a09 100644
--- a/lint/libs/lint_checks/src/com/android/tools/lint/checks/UnusedResourceDetector.java
+++ b/lint/libs/lint_checks/src/com/android/tools/lint/checks/UnusedResourceDetector.java
@@ -227,7 +227,7 @@ public class UnusedResourceDetector extends ResourceXmlDetector implements Detec
                 unused.removeAll(ids);
             }
 
-            if (unused.size() > 0) {
+            if (unused.size() > 0 && !context.getDriver().hasParserErrors()) {
                 mUnused = new HashMap<String, Location>(unused.size());
                 for (String resource : unused) {
                     mUnused.put(resource, null);
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/UnusedResourceDetectorTest.java b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/UnusedResourceDetectorTest.java
index c21c1b1..4bd5a88 100644
--- a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/UnusedResourceDetectorTest.java
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/UnusedResourceDetectorTest.java
@@ -252,4 +252,16 @@ public class UnusedResourceDetectorTest extends AbstractCheckTest {
 
            checkLint(Arrays.asList(master, library)));
     }
+
+    public void testCornerCase() throws Exception {
+        // See http://code.google.com/p/projectlombok/issues/detail?id=415
+        mEnableIds = true;
+        assertEquals(
+            "No warnings.",
+
+             lintProject(
+                 "res/layout/accessibility.xml",
+                 "src/test/pkg/Foo.java.txt=>src/test/pkg/Foo.java",
+                 "AndroidManifest.xml"));
+    }
 }
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/src/test/pkg/Foo.java.txt b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/src/test/pkg/Foo.java.txt
new file mode 100644
index 0000000..6e16a72
--- /dev/null
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/src/test/pkg/Foo.java.txt
@@ -0,0 +1,7 @@
+// http://code.google.com/p/projectlombok/issues/detail?id=415
+package test.pkg;
+public class X {
+  public void X(Y parent) {
+    parent.new Z(parent.getW()).execute();
+  }
+}