Fix Lint false positive for mixed XML/PNG Bitmap resource

This changeset fixes this issue:
http://code.google.com/p/android/issues/detail?id=23214

The icon detector makes sure that if an icon appears in a given -dpi
folder, it appears in all the other -dpi folders as well (except for
-nodpi). However, in the set comparison it would use the full filename
(including file extension), which is not correct since it's okay to
have an .9.png in one folder and a .gif in another (and as reported in
this bug, an .xml file).

This changeset also associates a file location with folder warnings
for a missing density folder (it uses the res folder), which made
various unit tests need updates since the results sort differently.

Change-Id: I7f09772f3a54683a9d0c5c5d93ae2499707f533a

5 files changed, 141 insertions, 14 deletions

diff --git a/lint/libs/lint_api/src/com/android/tools/lint/client/api/DefaultSdkInfo.java b/lint/libs/lint_api/src/com/android/tools/lint/client/api/DefaultSdkInfo.java
index 7ca3fab..0392a6f 100644
--- a/lint/libs/lint_api/src/com/android/tools/lint/client/api/DefaultSdkInfo.java
+++ b/lint/libs/lint_api/src/com/android/tools/lint/client/api/DefaultSdkInfo.java
@@ -179,7 +179,7 @@ class DefaultSdkInfo extends SdkInfo {
         PARENTS.put("MultiAutoCompleteTextView",          //$NON-NLS-1$
                 "AutoCompleteTextView");                  //$NON-NLS-1$
 
-        assert PARENTS.size() == CLASS_COUNT;
+        assert PARENTS.size() == CLASS_COUNT : PARENTS.size();
 
         /*
         // Check that all widgets lead to the root view
diff --git a/lint/libs/lint_api/src/com/android/tools/lint/detector/api/LintUtils.java b/lint/libs/lint_api/src/com/android/tools/lint/detector/api/LintUtils.java
index 186a5f3..4dbcbb3 100644
--- a/lint/libs/lint_api/src/com/android/tools/lint/detector/api/LintUtils.java
+++ b/lint/libs/lint_api/src/com/android/tools/lint/detector/api/LintUtils.java
@@ -115,6 +115,21 @@ public class LintUtils {
     }
 
     /**
+     * Returns the basename of the given filename, unless it's a dot-file such as ".svn".
+     *
+     * @param fileName the file name to extract the basename from
+     * @return the basename (the filename without the file extension)
+     */
+    public static String getBaseName(String fileName) {
+        int extension = fileName.indexOf('.');
+        if (extension > 0) {
+            return fileName.substring(0, extension);
+        } else {
+            return fileName;
+        }
+    }
+
+    /**
      * Returns the children elements of the given node
      *
      * @param node the parent node
diff --git a/lint/libs/lint_checks/src/com/android/tools/lint/checks/IconDetector.java b/lint/libs/lint_checks/src/com/android/tools/lint/checks/IconDetector.java
index 5f7adcb..56941bb 100644
--- a/lint/libs/lint_checks/src/com/android/tools/lint/checks/IconDetector.java
+++ b/lint/libs/lint_checks/src/com/android/tools/lint/checks/IconDetector.java
@@ -44,7 +44,6 @@ import com.android.tools.lint.detector.api.Scope;
 import com.android.tools.lint.detector.api.Severity;
 import com.android.tools.lint.detector.api.Speed;
 import com.android.tools.lint.detector.api.XmlContext;
-import com.google.common.collect.Sets;
 import com.google.common.io.Files;
 
 import org.w3c.dom.Element;
@@ -300,7 +299,7 @@ public class IconDetector extends Detector implements Detector.XmlScanner {
                                 Set<String> names = new HashSet<String>(files.length);
                                 for (File f : files) {
                                     String name = f.getName();
-                                    if (hasBitmapExtension(name)) {
+                                    if (isDrawableFile(name)) {
                                         names.add(f.getName());
                                     }
                                 }
@@ -325,9 +324,10 @@ public class IconDetector extends Detector implements Detector.XmlScanner {
         }
     }
 
-    private static boolean hasBitmapExtension(String name) {
+    private static boolean isDrawableFile(String name) {
         // endsWith(name, DOT_PNG) is also true for endsWith(name, DOT_9PNG)
-        return endsWith(name, DOT_PNG)|| endsWith(name, DOT_JPG) || endsWith(name, DOT_GIF);
+        return endsWith(name, DOT_PNG)|| endsWith(name, DOT_JPG) || endsWith(name, DOT_GIF) ||
+                endsWith(name, DOT_XML);
     }
 
     // This method looks for duplicates in the assets. This uses two pieces of information
@@ -740,7 +740,7 @@ public class IconDetector extends Detector implements Detector.XmlScanner {
             if (missing.size() > 0 ) {
                 context.report(
                     ICON_MISSING_FOLDER,
-                    null /* location */,
+                    Location.create(res),
                     String.format("Missing density variation folders in %1$s: %2$s",
                             context.getProject().getDisplayPath(res),
                             LintUtils.formatList(missing, missing.size())),
@@ -764,7 +764,7 @@ public class IconDetector extends Detector implements Detector.XmlScanner {
                     String folderName = folder.getName();
                     if (!isNoDpiFolder(folder)) {
                         assert DENSITY_PATTERN.matcher(folderName).matches();
-                        Set<String> overlap = Sets.intersection(noDpiNames, entry.getValue());
+                        Set<String> overlap = nameIntersection(noDpiNames, entry.getValue());
                         inBoth.addAll(overlap);
                         for (String name : overlap) {
                             files.add(new File(folder, name));
@@ -811,8 +811,10 @@ public class IconDetector extends Detector implements Detector.XmlScanner {
                 }
                 Set<String> names = entry.getValue();
                 if (names.size() != allNames.size()) {
-                    List<String> delta =
-                            new ArrayList<String>(Sets.difference(allNames,  names));
+                    List<String> delta = new ArrayList<String>(nameDifferences(allNames,  names));
+                    if (delta.size() == 0) {
+                        continue;
+                    }
                     Collections.sort(delta);
                     String foundIn = "";
                     if (delta.size() == 1) {
@@ -842,6 +844,81 @@ public class IconDetector extends Detector implements Detector.XmlScanner {
         }
     }
 
+    /**
+     * Compute the difference in names between a and b. This is not just
+     * Sets.difference(a, b) because we want to make the comparisons <b>without
+     * file extensions</b> and return the result <b>with</b>..
+     */
+    private Set<String> nameDifferences(Set<String> a, Set<String> b) {
+        Set<String> names1 = new HashSet<String>(a.size());
+        for (String s : a) {
+            names1.add(LintUtils.getBaseName(s));
+        }
+        Set<String> names2 = new HashSet<String>(b.size());
+        for (String s : b) {
+            names2.add(LintUtils.getBaseName(s));
+        }
+
+        names1.removeAll(names2);
+
+        if (names1.size() > 0) {
+            // Map filenames back to original filenames with extensions
+            Set<String> result = new HashSet<String>(names1.size());
+            for (String s : a) {
+                if (names1.contains(LintUtils.getBaseName(s))) {
+                    result.add(s);
+                }
+            }
+            for (String s : b) {
+                if (names1.contains(LintUtils.getBaseName(s))) {
+                    result.add(s);
+                }
+            }
+
+            return result;
+        }
+
+        return Collections.emptySet();
+    }
+
+    /**
+     * Compute the intersection in names between a and b. This is not just
+     * Sets.intersection(a, b) because we want to make the comparisons <b>without
+     * file extensions</b> and return the result <b>with</b>.
+     */
+    private Set<String> nameIntersection(Set<String> a, Set<String> b) {
+        Set<String> names1 = new HashSet<String>(a.size());
+        for (String s : a) {
+            names1.add(LintUtils.getBaseName(s));
+        }
+        Set<String> names2 = new HashSet<String>(b.size());
+        for (String s : b) {
+            names2.add(LintUtils.getBaseName(s));
+        }
+
+        names1.retainAll(names2);
+
+        if (names1.size() > 0) {
+            // Map filenames back to original filenames with extensions
+            Set<String> result = new HashSet<String>(names1.size());
+            for (String s : a) {
+                if (names1.contains(LintUtils.getBaseName(s))) {
+                    result.add(s);
+                }
+            }
+            for (String s : b) {
+                if (names1.contains(LintUtils.getBaseName(s))) {
+                    result.add(s);
+                }
+            }
+
+            return result;
+        }
+
+
+        return Collections.emptySet();
+    }
+
     private static boolean isNoDpiFolder(File file) {
         return file.getName().contains("-nodpi");
     }
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/IconDetectorTest.java b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/IconDetectorTest.java
index 7c105ad..d6da23d 100644
--- a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/IconDetectorTest.java
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/IconDetectorTest.java
@@ -27,11 +27,12 @@ public class IconDetectorTest extends AbstractCheckTest {
 
     public void test() throws Exception {
         assertEquals(
-            "Warning: Missing density variation folders in res: drawable-xhdpi\n" +
             "drawable-hdpi: Warning: Missing the following drawables in drawable-hdpi: sample_icon.gif (found in drawable-mdpi)\n" +
             "drawable/ic_launcher.png: Warning: The ic_launcher.png icon has identical contents in the following configuration folders: drawable-mdpi, drawable\n" +
             "ic_launcher.png: Warning: Found bitmap drawable res/drawable/ic_launcher.png in densityless folder\n" +
+            "res: Warning: Missing density variation folders in res: drawable-xhdpi\n" +
             "sample_icon.gif: Warning: Using the .gif format for bitmaps is discouraged",
+
             lintProject(
                     "res/drawable/ic_launcher.png",
                     "res/drawable/ic_launcher.png=>res/drawable-mdpi/ic_launcher.png",
@@ -44,9 +45,10 @@ public class IconDetectorTest extends AbstractCheckTest {
 
     public void test2() throws Exception {
         assertEquals(
-            "Warning: Missing density variation folders in res: drawable-mdpi, drawable-xhdpi\n" +
             "drawable-hdpi/other.9.png: Warning: The following unrelated icon files have identical contents: appwidget_bg.9.png, other.9.png\n" +
-            "drawable-hdpi/unrelated.png: Warning: The following unrelated icon files have identical contents: ic_launcher.png, unrelated.png",
+            "drawable-hdpi/unrelated.png: Warning: The following unrelated icon files have identical contents: ic_launcher.png, unrelated.png\n" +
+            "res: Warning: Missing density variation folders in res: drawable-mdpi, drawable-xhdpi",
+
             lintProject(
                     "res/drawable-hdpi/unrelated.png",
                     "res/drawable-hdpi/appwidget_bg.9.png",
@@ -58,9 +60,10 @@ public class IconDetectorTest extends AbstractCheckTest {
 
     public void testNoDpi() throws Exception {
         assertEquals(
-            "Warning: Missing density variation folders in res: drawable-hdpi, drawable-xhdpi\n" +
             "drawable-xlarge-nodpi-v11/frame.png: Warning: The frame.png icon has identical contents in the following configuration folders: drawable-mdpi, drawable-nodpi, drawable-xlarge-nodpi-v11\n" +
-            "frame.png: Warning: The following images appear in both -nodpi and in a density folder: frame.png",
+            "frame.png: Warning: The following images appear in both -nodpi and in a density folder: frame.png\n" +
+            "res: Warning: Missing density variation folders in res: drawable-hdpi, drawable-xhdpi",
+
             lintProject(
                 "res/drawable-mdpi/frame.png",
                 "res/drawable-nodpi/frame.png",
@@ -81,4 +84,30 @@ public class IconDetectorTest extends AbstractCheckTest {
                     "res/drawable-mdpi/frame.png=>res/drawable-nodpi/file1.png",
                     "res/drawable-mdpi/frame.png=>res/drawable-nodpi/file2.png"));
     }
+
+    public void testNoDpiMix() throws Exception {
+        assertEquals(
+            "drawable-mdpi/frame.xml: Warning: The following images appear in both -nodpi and in a density folder: frame.png, frame.xml\n" +
+            "res: Warning: Missing density variation folders in res: drawable-hdpi, drawable-xhdpi",
+
+            lintProject(
+                "res/drawable-mdpi/frame.png",
+                "res/drawable/states.xml=>res/drawable-nodpi/frame.xml"));
+    }
+
+
+    public void testMixedFormat() throws Exception {
+        // Test having a mixture of .xml and .png resources for the same name
+        // Make sure we don't get:
+        // drawable-hdpi: Warning: Missing the following drawables in drawable-hdpi: f.png (found in drawable-mdpi)
+        // drawable-xhdpi: Warning: Missing the following drawables in drawable-xhdpi: f.png (found in drawable-mdpi)
+        assertEquals(
+            "No warnings.",
+
+            lintProject(
+                    "res/drawable-mdpi/frame.png=>res/drawable-mdpi/f.png",
+                    "res/drawable/states.xml=>res/drawable-hdpi/f.xml",
+                    "res/drawable/states.xml=>res/drawable-xhdpi/f.xml"));
+    }
+
 }
\ No newline at end of file
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/detector/api/LintUtilsTest.java b/lint/libs/lint_checks/tests/src/com/android/tools/lint/detector/api/LintUtilsTest.java
index ba3df3b..6f585b0 100644
--- a/lint/libs/lint_checks/tests/src/com/android/tools/lint/detector/api/LintUtilsTest.java
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/detector/api/LintUtilsTest.java
@@ -46,6 +46,12 @@ public class LintUtilsTest extends TestCase {
         assertFalse(LintUtils.isXmlFile(new File("xml.png")));
     }
 
+    public void testGetBasename() throws Exception {
+        assertEquals("foo", LintUtils.getBaseName("foo.png"));
+        assertEquals("foo", LintUtils.getBaseName("foo.9.png"));
+        assertEquals(".foo", LintUtils.getBaseName(".foo"));
+    }
+
     public void testEditDistance() {
         assertEquals(0, LintUtils.editDistance("kitten", "kitten"));