Fix a bug with the whitelist

This bug would kill the case where the whitelist contains
a word to be autocorrected to an uppercased version of
itself, and the user would enter the uppercase version.
In this case, this bug would cause the typed word to be
killed off the list of candidates, and possibly autocorrected
to the *next* candidate.

When the whitelist checks whether this the typed word is
a candidate for whitelisting, this change has it check whether
the whitelisting results in the typed word before returning.
Hence, it can keep the case-insensitive behavior of the
whitelist.

Coincidentally, this change renames the method used to do
this, because it does not comply with the general contract
of Dictionary. This happens to be in the way of another
upcoming change.

Bug: 5420371
Change-Id: Ifb305271acc5f171adf9b18c762ae7975b14be0a

java/src/com/android/inputmethod/latin/AutoCorrection.java

@@ -82,14 +82,16 @@ public class AutoCorrection {
         return false;
     }
 
-    public static boolean isValidWordForAutoCorrection(
+    public static boolean allowsToBeAutoCorrected(
             Map<String, Dictionary> dictionaries, CharSequence word, boolean ignoreCase) {
-        final Dictionary whiteList = dictionaries.get(Suggest.DICT_KEY_WHITELIST);
+        final WhitelistDictionary whitelistDictionary =
+                (WhitelistDictionary)dictionaries.get(Suggest.DICT_KEY_WHITELIST);
         // If "word" is in the whitelist dictionary, it should not be auto corrected.
-        if (whiteList != null && whiteList.isValidWord(word)) {
-            return false;
+        if (whitelistDictionary != null
+                && whitelistDictionary.shouldForciblyAutoCorrectFrom(word)) {
+            return true;
         }
-        return isValidWord(dictionaries, word, ignoreCase);
+        return !isValidWord(dictionaries, word, ignoreCase);
     }
 
     private static boolean hasAutoCorrectionForWhitelistedWord(CharSequence whiteListedWord) {
@@ -100,8 +102,8 @@ public class AutoCorrection {
             WordComposer wordComposer, ArrayList<CharSequence> suggestions, CharSequence typedWord,
             int correctionMode) {
         if (TextUtils.isEmpty(typedWord)) return false;
-        boolean isValidWord = isValidWordForAutoCorrection(dictionaries, typedWord, false);
-        return wordComposer.size() > 1 && suggestions.size() > 0 && isValidWord
+        boolean allowsAutoCorrect = allowsToBeAutoCorrected(dictionaries, typedWord, false);
+        return wordComposer.size() > 1 && suggestions.size() > 0 && !allowsAutoCorrect
                 && (correctionMode == Suggest.CORRECTION_FULL
                 || correctionMode == Suggest.CORRECTION_FULL_BIGRAM);
     }

java/src/com/android/inputmethod/latin/LatinIME.java

@@ -1634,11 +1634,16 @@ public class LatinIME extends InputMethodServiceCompatWrapper implements Keyboar
         boolean autoCorrectionAvailable = !mInputTypeNoAutoCorrect && mSuggest.hasAutoCorrection();
         final CharSequence typedWord = wordComposer.getTypedWord();
         // Here, we want to promote a whitelisted word if exists.
-        final boolean typedWordValid = AutoCorrection.isValidWordForAutoCorrection(
+        // TODO: Change this scheme - a boolean is not enough. A whitelisted word may be "valid"
+        // but still autocorrected from - in the case the whitelist only capitalizes the word.
+        // The whitelist should be case-insensitive, so it's not possible to be consistent with
+        // a boolean flag. Right now this is handled with a slight hack in
+        // WhitelistDictionary#shouldForciblyAutoCorrectFrom.
+        final boolean allowsToBeAutoCorrected = AutoCorrection.allowsToBeAutoCorrected(
                 mSuggest.getUnigramDictionaries(), typedWord, preferCapitalization());
         if (mCorrectionMode == Suggest.CORRECTION_FULL
                 || mCorrectionMode == Suggest.CORRECTION_FULL_BIGRAM) {
-            autoCorrectionAvailable |= typedWordValid;
+            autoCorrectionAvailable |= (!allowsToBeAutoCorrected);
         }
         // Don't auto-correct words with multiple capital letter
         autoCorrectionAvailable &= !wordComposer.isMostlyCaps();
@@ -1651,9 +1656,9 @@ public class LatinIME extends InputMethodServiceCompatWrapper implements Keyboar
         // need to clear the previous state when the user starts typing a word (i.e. typed word's
         // length == 1).
         if (typedWord != null) {
-            if (builder.size() > 1 || typedWord.length() == 1 || typedWordValid
+            if (builder.size() > 1 || typedWord.length() == 1 || (!allowsToBeAutoCorrected)
                     || mSuggestionsView.isShowingAddToDictionaryHint()) {
-                builder.setTypedWordValid(typedWordValid).setHasMinimalSuggestion(
+                builder.setTypedWordValid(!allowsToBeAutoCorrected).setHasMinimalSuggestion(
                         autoCorrectionAvailable);
             } else {
                 SuggestedWords previousSuggestions = mSuggestionsView.getSuggestions();

java/src/com/android/inputmethod/latin/WhitelistDictionary.java

@@ -93,4 +93,20 @@ public class WhitelistDictionary extends Dictionary {
         if (TextUtils.isEmpty(word)) return false;
         return !TextUtils.isEmpty(getWhiteListedWord(word.toString()));
     }
+
+    // See LatinIME#updateSuggestions. This breaks in the (queer) case that the whitelist
+    // lists that word a should autocorrect to word b, and word c would autocorrect to
+    // an upper-cased version of a. In this case, the way this return value is used would
+    // remove the first candidate when the user typed the upper-cased version of A.
+    // Example : abc -> def  and  xyz -> Abc
+    // A user typing Abc would experience it being autocorrected to something else (not
+    // necessarily def).
+    // There is no such combination in the whitelist at the time and there probably won't
+    // ever be - it doesn't make sense. But still.
+    public boolean shouldForciblyAutoCorrectFrom(CharSequence word) {
+        if (TextUtils.isEmpty(word)) return false;
+        final String correction = getWhiteListedWord(word.toString());
+        if (TextUtils.isEmpty(correction)) return false;
+        return !correction.equals(word);
+    }
 }

tests/src/com/android/inputmethod/latin/SuggestHelper.java

@@ -89,7 +89,7 @@ public class SuggestHelper {
     }
 
     public boolean isValidWord(CharSequence typed) {
-        return AutoCorrection.isValidWordForAutoCorrection(mSuggest.getUnigramDictionaries(),
+        return AutoCorrection.isValidWord(mSuggest.getUnigramDictionaries(),
                 typed, false);
     }