lint/libs/lint-checks/src/main/java/com/android/tools/lint/checks/DeprecationDetector.java

/*
 * Copyright (C) 2011 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.ABSOLUTE_LAYOUT;
import static com.android.SdkConstants.ANDROID_URI;
import static com.android.SdkConstants.ATTR_AUTO_TEXT;
import static com.android.SdkConstants.ATTR_CAPITALIZE;
import static com.android.SdkConstants.ATTR_EDITABLE;
import static com.android.SdkConstants.ATTR_ENABLED;
import static com.android.SdkConstants.ATTR_INPUT_METHOD;
import static com.android.SdkConstants.ATTR_NUMERIC;
import static com.android.SdkConstants.ATTR_PASSWORD;
import static com.android.SdkConstants.ATTR_PHONE_NUMBER;
import static com.android.SdkConstants.ATTR_SINGLE_LINE;
import static com.android.SdkConstants.EDIT_TEXT;
import static com.android.SdkConstants.VALUE_TRUE;

import com.android.annotations.NonNull;
import com.android.tools.lint.detector.api.Category;
import com.android.tools.lint.detector.api.Implementation;
import com.android.tools.lint.detector.api.Issue;
import com.android.tools.lint.detector.api.LayoutDetector;
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 org.w3c.dom.Attr;
import org.w3c.dom.Element;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;

/**
 * Check which looks for usage of deprecated tags, attributes, etc.
 */
public class DeprecationDetector extends LayoutDetector {
    /** Usage of deprecated views or attributes */
    public static final Issue ISSUE = Issue.create(
            "Deprecated", //$NON-NLS-1$
            "Using deprecated resources",
            "Deprecated views, attributes and so on are deprecated because there " +
            "is a better way to do something. Do it that new way. You've been warned.",
            Category.CORRECTNESS,
            2,
            Severity.WARNING,
            new Implementation(
                    DeprecationDetector.class,
                    Scope.RESOURCE_FILE_SCOPE));

    /** Constructs a new {@link DeprecationDetector} */
    public DeprecationDetector() {
    }

    @NonNull
    @Override
    public Speed getSpeed() {
        return Speed.FAST;
    }

    @Override
    public Collection<String> getApplicableElements() {
        return Collections.singletonList(
                ABSOLUTE_LAYOUT
        );
    }

    @Override
    public Collection<String> getApplicableAttributes() {
        return Arrays.asList(
                // TODO: fill_parent is deprecated as of API 8.
                // We could warn about it, but it will probably be very noisy
                // and make people disable the deprecation check; let's focus on
                // some older flags for now
                //"fill_parent",

                ATTR_EDITABLE,
                ATTR_INPUT_METHOD,
                ATTR_AUTO_TEXT,
                ATTR_CAPITALIZE,

                // This flag is still used a lot and is still properly handled by TextView
                // so in the interest of not being too noisy and make people ignore all the
                // output, keep quiet about this one -for now-.
                //ATTR_SINGLE_LINE,

                // This attribute is marked deprecated in android.R.attr but apparently
                // using the suggested replacement of state_enabled doesn't work, see issue 27613
                //ATTR_ENABLED,

                ATTR_NUMERIC,
                ATTR_PHONE_NUMBER,
                ATTR_PASSWORD

                // These attributes are also deprecated; not yet enabled until we
                // know the API level to apply the deprecation for:

                // "ignored as of ICS (but deprecated earlier)"
                //"fadingEdge",

                // "This attribute is not used by the Android operating system."
                //"restoreNeedsApplication",

                // "This will create a non-standard UI appearance, because the search bar UI is
                // changing to use only icons for its buttons."
                //"searchButtonText",

        );
    }

    @Override
    public void visitElement(@NonNull XmlContext context, @NonNull Element element) {
        context.report(ISSUE, element, context.getLocation(element),
                String.format("`%1$s` is deprecated", element.getTagName()));
    }

    @Override
    public void visitAttribute(@NonNull XmlContext context, @NonNull Attr attribute) {
        if (!ANDROID_URI.equals(attribute.getNamespaceURI())) {
            return;
        }

        String name = attribute.getLocalName();
        String fix;
        int minSdk = 1;
        if (name.equals(ATTR_EDITABLE)) {
            if (!EDIT_TEXT.equals(attribute.getOwnerElement().getTagName())) {
                fix = "Use an `<EditText>` to make it editable";
            } else {
                if (VALUE_TRUE.equals(attribute.getValue())) {
                    fix = "`<EditText>` is already editable";
                } else {
                    fix = "Use `inputType` instead";
                }
            }
        } else if (name.equals(ATTR_ENABLED)) {
            fix = "Use `state_enabled` instead";
        } else if (name.equals(ATTR_SINGLE_LINE)) {
            fix = "Use `maxLines=\"1\"` instead";
        } else {
            assert name.equals(ATTR_INPUT_METHOD)
                || name.equals(ATTR_CAPITALIZE)
                || name.equals(ATTR_NUMERIC)
                || name.equals(ATTR_PHONE_NUMBER)
                || name.equals(ATTR_PASSWORD)
                || name.equals(ATTR_AUTO_TEXT);
            fix = "Use `inputType` instead";
            // The inputType attribute was introduced in API 3 so don't warn about
            // deprecation if targeting older platforms
            minSdk = 3;
        }

        if (context.getProject().getMinSdk() < minSdk) {
            return;
        }

        context.report(ISSUE, attribute, context.getLocation(attribute),
                String.format("`%1$s` is deprecated: %2$s",
                        attribute.getName(), fix));
    }
}