Add labelFor lint check

Change-Id: If2b905197d5d81c6f98315a0d48ff37091e8282b

7 files changed, 360 insertions, 4 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 1e53834..b5ae26d 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
@@ -21,6 +21,7 @@ import static com.android.SdkConstants.ABS_LIST_VIEW;
 import static com.android.SdkConstants.ABS_SEEK_BAR;
 import static com.android.SdkConstants.ABS_SPINNER;
 import static com.android.SdkConstants.ADAPTER_VIEW;
+import static com.android.SdkConstants.AUTO_COMPLETE_TEXT_VIEW;
 import static com.android.SdkConstants.BUTTON;
 import static com.android.SdkConstants.CHECKED_TEXT_VIEW;
 import static com.android.SdkConstants.CHECK_BOX;
@@ -35,6 +36,7 @@ import static com.android.SdkConstants.IMAGE_BUTTON;
 import static com.android.SdkConstants.IMAGE_VIEW;
 import static com.android.SdkConstants.LINEAR_LAYOUT;
 import static com.android.SdkConstants.LIST_VIEW;
+import static com.android.SdkConstants.MULTI_AUTO_COMPLETE_TEXT_VIEW;
 import static com.android.SdkConstants.PROGRESS_BAR;
 import static com.android.SdkConstants.RADIO_BUTTON;
 import static com.android.SdkConstants.RADIO_GROUP;
@@ -191,6 +193,8 @@ class DefaultSdkInfo extends SdkInfo {
         PARENTS.put(SCROLL_VIEW, FRAME_LAYOUT);
         PARENTS.put(GRID_VIEW, ABS_LIST_VIEW);
         PARENTS.put(WEB_VIEW, ABSOLUTE_LAYOUT);
+        PARENTS.put(AUTO_COMPLETE_TEXT_VIEW, EDIT_TEXT);
+        PARENTS.put(MULTI_AUTO_COMPLETE_TEXT_VIEW, AUTO_COMPLETE_TEXT_VIEW);
 
         PARENTS.put("CheckedTextView", TEXT_VIEW);        //$NON-NLS-1$
         PARENTS.put("MediaController", FRAME_LAYOUT);     //$NON-NLS-1$
@@ -207,12 +211,9 @@ class DefaultSdkInfo extends SdkInfo {
         PARENTS.put("TimePicker", FRAME_LAYOUT);          //$NON-NLS-1$
         PARENTS.put("VideoView", SURFACE_VIEW);           //$NON-NLS-1$
         PARENTS.put("ZoomButton", IMAGE_BUTTON);          //$NON-NLS-1$
-        PARENTS.put("AutoCompleteTextView", EDIT_TEXT);   //$NON-NLS-1$
         PARENTS.put("RatingBar", ABS_SEEK_BAR);           //$NON-NLS-1$
         PARENTS.put("ViewFlipper", VIEW_ANIMATOR);        //$NON-NLS-1$
         PARENTS.put("NumberPicker", LINEAR_LAYOUT);       //$NON-NLS-1$
-        PARENTS.put("MultiAutoCompleteTextView",          //$NON-NLS-1$
-                "AutoCompleteTextView");                  //$NON-NLS-1$
 
         assert PARENTS.size() <= CLASS_COUNT : PARENTS.size();
 
diff --git a/lint/libs/lint_checks/src/com/android/tools/lint/checks/BuiltinIssueRegistry.java b/lint/libs/lint_checks/src/com/android/tools/lint/checks/BuiltinIssueRegistry.java
index ca73df0..c5e4e64 100644
--- a/lint/libs/lint_checks/src/com/android/tools/lint/checks/BuiltinIssueRegistry.java
+++ b/lint/libs/lint_checks/src/com/android/tools/lint/checks/BuiltinIssueRegistry.java
@@ -55,10 +55,11 @@ public class BuiltinIssueRegistry extends IssueRegistry {
     private static final List<Issue> sIssues;
 
     static {
-        final int initialCapacity = 109;
+        final int initialCapacity = 110;
         List<Issue> issues = new ArrayList<Issue>(initialCapacity);
 
         issues.add(AccessibilityDetector.ISSUE);
+        issues.add(LabelForDetector.ISSUE);
         issues.add(MathDetector.ISSUE);
         issues.add(FieldGetterDetector.ISSUE);
         issues.add(SdCardDetector.ISSUE);
diff --git a/lint/libs/lint_checks/src/com/android/tools/lint/checks/LabelForDetector.java b/lint/libs/lint_checks/src/com/android/tools/lint/checks/LabelForDetector.java
new file mode 100644
index 0000000..74e510d
--- /dev/null
+++ b/lint/libs/lint_checks/src/com/android/tools/lint/checks/LabelForDetector.java
@@ -0,0 +1,163 @@
+/*
+ * Copyright (C) 2012 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.tools.lint.checks;
+
+import static com.android.SdkConstants.ANDROID_URI;
+import static com.android.SdkConstants.ATTR_ID;
+import static com.android.SdkConstants.ATTR_LABEL_FOR;
+import static com.android.SdkConstants.AUTO_COMPLETE_TEXT_VIEW;
+import static com.android.SdkConstants.EDIT_TEXT;
+import static com.android.SdkConstants.ID_PREFIX;
+import static com.android.SdkConstants.MULTI_AUTO_COMPLETE_TEXT_VIEW;
+import static com.android.SdkConstants.NEW_ID_PREFIX;
+import static com.android.tools.lint.detector.api.LintUtils.stripIdPrefix;
+
+import com.android.annotations.NonNull;
+import com.android.annotations.Nullable;
+import com.android.tools.lint.detector.api.Category;
+import com.android.tools.lint.detector.api.Context;
+import com.android.tools.lint.detector.api.Issue;
+import com.android.tools.lint.detector.api.LayoutDetector;
+import com.android.tools.lint.detector.api.Location;
+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 org.w3c.dom.Attr;
+import org.w3c.dom.Element;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Detector which finds unlabeled text fields
+ */
+public class LabelForDetector extends LayoutDetector {
+    /** The main issue discovered by this detector */
+    public static final Issue ISSUE = Issue.create(
+            "LabelFor", //$NON-NLS-1$
+            "Ensures that text fields are marked with a labelFor attribute",
+            "Text fields should be labelled with a `labelFor` attribute, " +
+            "provided your `minSdkVersion` is at least 17.\n" +
+            "\n" +
+            "If your view is labeled but by a label in a different layout which " +
+            "includes this one, just suppress this warning from lint.",
+            Category.A11Y,
+            2,
+            Severity.WARNING,
+            LabelForDetector.class,
+            Scope.RESOURCE_FILE_SCOPE);
+
+    private Set<String> mLabels;
+    private List<Element> mTextFields;
+
+    /** Constructs a new {@link LabelForDetector} */
+    public LabelForDetector() {
+    }
+
+    @Override
+    public @NonNull Speed getSpeed() {
+        return Speed.FAST;
+    }
+
+    @Override
+    @Nullable
+    public Collection<String> getApplicableAttributes() {
+        return Collections.singletonList(ATTR_LABEL_FOR);
+    }
+
+    @Override
+    public Collection<String> getApplicableElements() {
+        return Arrays.asList(
+                EDIT_TEXT,
+                AUTO_COMPLETE_TEXT_VIEW,
+                MULTI_AUTO_COMPLETE_TEXT_VIEW
+        );
+    }
+
+    @Override
+    public void afterCheckFile(@NonNull Context context) {
+        if (mTextFields != null) {
+            if (mLabels == null) {
+                mLabels = Collections.emptySet();
+            }
+
+            for (Element element : mTextFields) {
+                String id = element.getAttributeNS(ANDROID_URI, ATTR_ID);
+                boolean missing = true;
+                if (mLabels.contains(id)) {
+                    missing = false;
+                } else if (id.startsWith(NEW_ID_PREFIX)) {
+                    missing = !mLabels.contains(ID_PREFIX + stripIdPrefix(id));
+                } else if (id.startsWith(ID_PREFIX)) {
+                    missing = !mLabels.contains(NEW_ID_PREFIX + stripIdPrefix(id));
+                }
+
+                if (missing) {
+                    XmlContext xmlContext = (XmlContext) context;
+                    Location location = xmlContext.getLocation(element);
+                    String message;
+                    if (id == null || id.isEmpty()) {
+                        message = "No label views point to this text field with a " +
+                                "labelFor attribute";
+                    } else {
+                        message = String.format("No label views point to this text field with " +
+                                "an android:labelFor=\"@+id/%1$s\" attribute", id);
+                    }
+                    xmlContext.report(ISSUE, element, location, message, null);
+                }
+
+            }
+        }
+
+        mLabels = null;
+        mTextFields = null;
+    }
+
+    @Override
+    public void visitAttribute(@NonNull XmlContext context, @NonNull Attr attribute) {
+        if (mLabels == null) {
+            mLabels = Sets.newHashSet();
+        }
+        mLabels.add(attribute.getValue());
+    }
+
+    @Override
+    public void visitElement(@NonNull XmlContext context, @NonNull Element element) {
+        // NOTE: This should NOT be checking *minSdkVersion*, but *targetSdkVersion*
+        // or even buildTarget instead. However, there's a risk that this will flag
+        // way too much and make the rule annoying until API 17 support becomes
+        // more widespread, so for now limit the check to those projects *really*
+        // working with 17.  When API 17 reaches a certain amount of adoption, change
+        // this to flag all apps supporting 17, including those supporting earlier
+        // versions as well.
+        if (context.getMainProject().getMinSdk() < 17) {
+            return;
+        }
+
+        if (mTextFields == null) {
+            mTextFields = new ArrayList<Element>();
+        }
+        mTextFields.add(element);
+    }
+}
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/LabelForDetectorTest.java b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/LabelForDetectorTest.java
new file mode 100644
index 0000000..7e139af
--- /dev/null
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/LabelForDetectorTest.java
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Eclipse Public License, Version 1.0 (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.eclipse.org/org/documents/epl-v10.php
+ *
+ * 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.tools.lint.checks;
+
+import com.android.tools.lint.detector.api.Detector;
+
+@SuppressWarnings("javadoc")
+public class LabelForDetectorTest extends AbstractCheckTest {
+    @Override
+    protected Detector getDetector() {
+        return new LabelForDetector();
+    }
+
+    public void test() throws Exception {
+        assertEquals(
+        "res/layout/labelfor.xml:54: Warning: No label views point to this text field with an android:labelFor=\"@+id/@+id/editText2\" attribute [LabelFor]\n" +
+        "    <EditText\n" +
+        "    ^\n" +
+        "res/layout/labelfor.xml:61: Warning: No label views point to this text field with an android:labelFor=\"@+id/@+id/autoCompleteTextView2\" attribute [LabelFor]\n" +
+        "    <AutoCompleteTextView\n" +
+        "    ^\n" +
+        "res/layout/labelfor.xml:68: Warning: No label views point to this text field with an android:labelFor=\"@+id/@+id/multiAutoCompleteTextView2\" attribute [LabelFor]\n" +
+        "    <MultiAutoCompleteTextView\n" +
+        "    ^\n" +
+        "0 errors, 3 warnings\n",
+
+        lintProject(
+                "apicheck/minsdk17.xml=>AndroidManifest.xml",
+                "res/layout/labelfor.xml"
+        ));
+    }
+
+    public void testSuppressed() throws Exception {
+        assertEquals(
+        "No warnings.",
+
+        lintProject(
+            "apicheck/minsdk17.xml=>AndroidManifest.xml",
+            "res/layout/labelfor_ignore.xml"
+        ));
+    }
+
+
+    public void testOk() throws Exception {
+        assertEquals(
+        "No warnings.",
+
+        lintProject(
+                "apicheck/minsdk17.xml=>AndroidManifest.xml",
+                "res/layout/accessibility.xml"
+            ));
+    }
+
+    public void testNotApplicable() throws Exception {
+        assertEquals(
+        "No warnings.",
+
+        lintProject(
+                "apicheck/minsdk14.xml=>AndroidManifest.xml",
+                "res/layout/labelfor.xml"
+        ));
+    }
+}
+
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/apicheck/minsdk17.xml b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/apicheck/minsdk17.xml
new file mode 100644
index 0000000..1837db9
--- /dev/null
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/apicheck/minsdk17.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="test.bytecode"
+    android:versionCode="1"
+    android:versionName="1.0" >
+
+    <uses-sdk android:minSdkVersion="17" />
+
+    <application
+        android:icon="@drawable/ic_launcher"
+        android:label="@string/app_name" >
+        <activity
+            android:name=".BytecodeTestsActivity"
+            android:label="@string/app_name" >
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+    </application>
+
+</manifest>
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/res/layout/labelfor.xml b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/res/layout/labelfor.xml
new file mode 100644
index 0000000..7eec47e
--- /dev/null
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/res/layout/labelfor.xml
@@ -0,0 +1,75 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical" >
+
+    <TextView
+        android:id="@+id/textView1"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:labelFor="@+id/editText1"
+        android:text="Medium Text"
+        android:textAppearance="?android:attr/textAppearanceMedium" />
+
+    <EditText
+        android:id="@+id/editText1"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:inputType="textPersonName" >
+
+        <requestFocus />
+    </EditText>
+
+    <TextView
+        android:id="@+id/textView2"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:labelFor="@+id/autoCompleteTextView1"
+        android:text="TextView" />
+
+    <AutoCompleteTextView
+        android:id="@+id/autoCompleteTextView1"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:text="AutoCompleteTextView" />
+
+    <TextView
+        android:id="@+id/textView3"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:labelFor="@+id/multiAutoCompleteTextView1"
+        android:text="Large Text"
+        android:textAppearance="?android:attr/textAppearanceLarge" />
+
+    <MultiAutoCompleteTextView
+        android:id="@+id/multiAutoCompleteTextView1"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:text="MultiAutoCompleteTextView" />
+
+    <EditText
+        android:id="@+id/editText2"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:inputType="textPostalAddress" />
+
+    <AutoCompleteTextView
+        android:id="@+id/autoCompleteTextView2"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:text="AutoCompleteTextView" />
+
+    <MultiAutoCompleteTextView
+        android:id="@+id/multiAutoCompleteTextView2"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:text="MultiAutoCompleteTextView" />
+
+</LinearLayout>
\ No newline at end of file
diff --git a/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/res/layout/labelfor_ignore.xml b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/res/layout/labelfor_ignore.xml
new file mode 100644
index 0000000..41d2821
--- /dev/null
+++ b/lint/libs/lint_checks/tests/src/com/android/tools/lint/checks/data/res/layout/labelfor_ignore.xml
@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical" >
+
+    <EditText
+        android:id="@+id/editText2"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:ems="10"
+        android:inputType="textPostalAddress"
+        tools:ignore="LabelFor"/>
+
+</LinearLayout>