Make resource folders customizeable

Until now, lint has hardcoded where the project resources are to be
found: in $project/res.

With the new build system this will no longer necessarily be the case;
there can be multiple resource folders, and the locations might not be
just res/.

Therefore, this CL generalizes lint's handling of resource folders: it
is now provided by the LintClient, and the command line lint tool uses
this to offer a new --resources flag which can be used to set the
resource directory/directories for a project.

Change-Id: I3717c6474141776ee5541d476f9bad5bb8e1a9c7

3 files changed, 22 insertions, 20 deletions

diff --git a/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintClient.java b/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintClient.java
index 9afef42..6c4b202 100644
--- a/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintClient.java
+++ b/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintClient.java
@@ -52,6 +52,7 @@ import java.io.IOException;
 import java.io.StringReader;
 import java.net.URL;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -236,20 +237,19 @@ public abstract class LintClient {
     }
 
     /**
-     * Returns the resource folder.
+     * Returns the resource folders.
      *
      * @param project the project to look up the resource folder for
-     * @return a file pointing to the resource folder, or null if the project
-     *         does not contain any resources
+     * @return a list of files pointing to the resource folders, possibly empty
      */
-    @Nullable
-    public File getResourceFolder(@NonNull Project project) {
+    @NonNull
+    public List<File> getResourceFolders(@NonNull Project project) {
         File res = new File(project.getDir(), RES_FOLDER);
         if (res.exists()) {
-            return res;
+            return Collections.singletonList(res);
         }
 
-        return null;
+        return Collections.emptyList();
     }
 
     /**
diff --git a/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintDriver.java b/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintDriver.java
index dd268a5..28168a6 100644
--- a/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintDriver.java
+++ b/lint/libs/lint_api/src/main/java/com/android/tools/lint/client/api/LintDriver.java
@@ -841,9 +841,11 @@ public class LintDriver {
                     if (files != null) {
                         checkIndividualResources(project, main, xmlDetectors, files);
                     } else {
-                        File res = project.getResourceFolder();
-                        if (res != null && !xmlDetectors.isEmpty()) {
-                            checkResFolder(project, main, res, xmlDetectors);
+                        List<File> resourceFolders = project.getResourceFolders();
+                        if (!resourceFolders.isEmpty() && !xmlDetectors.isEmpty()) {
+                            for (File res : resourceFolders) {
+                                checkResFolder(project, main, res, xmlDetectors);
+                            }
                         }
                     }
                 }
@@ -1686,9 +1688,9 @@ public class LintDriver {
         }
 
         @Override
-        @Nullable
-        public File getResourceFolder(@NonNull Project project) {
-            return mDelegate.getResourceFolder(project);
+        @NonNull
+        public List<File> getResourceFolders(@NonNull Project project) {
+            return mDelegate.getResourceFolders(project);
         }
 
         @Override
diff --git a/lint/libs/lint_api/src/main/java/com/android/tools/lint/detector/api/Project.java b/lint/libs/lint_api/src/main/java/com/android/tools/lint/detector/api/Project.java
index df27b2f..67c3b16 100644
--- a/lint/libs/lint_api/src/main/java/com/android/tools/lint/detector/api/Project.java
+++ b/lint/libs/lint_api/src/main/java/com/android/tools/lint/detector/api/Project.java
@@ -353,20 +353,20 @@ public class Project {
      * @return a file pointing to the resource folder, or null if the project
      *         does not contain any resources
      */
-    @Nullable
-    public File getResourceFolder() {
-        File folder = mClient.getResourceFolder(this);
+    @NonNull
+    public List<File> getResourceFolders() {
+        List<File> folders = mClient.getResourceFolders(this);
 
-        if (folder != null && isAospFrameworksProject(mDir)) {
+        if (folders.size() == 1 && isAospFrameworksProject(mDir)) {
             // No manifest file for this project: just init the manifest values here
             mMinSdk = mTargetSdk = SdkConstants.HIGHEST_KNOWN_API;
-            folder = new File(folder, RES_FOLDER);
+            File folder = new File(folders.get(0), RES_FOLDER);
             if (!folder.exists()) {
-                folder = null;
+                folders = Collections.emptyList();
             }
         }
 
-        return folder;
+        return folders;
     }
 
     /**