Trigger mention on whitespace removal rebased (#143)

Editing the mention should trigger the typeahead again - On removal of whitespace between control character and typed in string, it should trigger mention again - Updated state machine, to update the flow to trigger mention - When a control character is inserted before an already existing word, we would need the word to begin a mention with or replace the word with the selected mention
linkedin · Dec 9, 2019 · bee254a · bee254a
1 parent 734c5c4
commit bee254a
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Showing 6 changed files with 174 additions and 70 deletions.
diff --git a/Hakawai/Core/HKWTextView.h b/Hakawai/Core/HKWTextView.h
@@ -126,6 +126,12 @@ NS_ASSUME_NONNULL_BEGIN
  */
 @property (nonatomic, readonly) BOOL inSingleLineViewportMode;
 
+/*!
+ String that saves the state of the text in the text view so that it can be accessed in the NSTextStorageDelegate, which will
+ already have deleted the character by the time it's trying to process said deletion
+ */
+@property (nonatomic, strong, readonly) NSString *textStateBeforeDeletion;
+
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/Hakawai/Core/HKWTextView.m b/Hakawai/Core/HKWTextView.m
@@ -24,10 +24,7 @@
 @interface HKWTextView () <UITextViewDelegate, HKWAbstractionLayerDelegate, NSTextStorageDelegate>
 
 @property (nonatomic) NSMutableDictionary *simplePluginsDictionary;
-/*!
- String that saves the state of the text in the text view so that it can be accessed in the NSTextStorageDelegate, which will
- already have deleted the character by the time it's trying to process said deletion
- */
+
 @property (nonatomic, strong, readwrite) NSString *textStateBeforeDeletion;
 
 @end

diff --git a/Hakawai/Mentions/HKWMentionsCreationStateMachine.m b/Hakawai/Mentions/HKWMentionsCreationStateMachine.m
@@ -270,12 +270,33 @@ - (void)stringDeleted:(NSString *)deleteString {
 
     __strong __auto_type delegate = self.delegate;
 
+    /**
+     When mentions was originally triggered because the whitespace between a control character and a word was deleted,
+     the cursor is next to the control character (like "@|John", where '|' represents the cursor-state). If the user then deletes the control character,
+     the string buffer will not be empty (it will have "John" in it), but mentions has to stop, because control character is deleted.
+     We use the isControlCharacterDeleted flag to decide what to do in this case of control character deletion.
+     */
+    BOOL isControlCharacterDeleted = NO;
+    if (deleteString.length == 1
+        && [deleteString containsString:[NSString stringWithFormat:@"%C", self.explicitSearchControlCharacter]]
+        && self.stringBuffer.length > 0
+        && [self.stringBuffer characterAtIndex:self.stringBuffer.length - 1] != self.explicitSearchControlCharacter) {
+        isControlCharacterDeleted = YES;
+    }
+
     // Switch on the overall state
     switch (self.state) {
         case HKWMentionsCreationStateQuiescent:
             // User not creating a mention right now
             return;
         case HKWMentionsCreationStateCreatingMention:
+            if (isControlCharacterDeleted) {
+                // When user deletes control character during mention creation state, then end mention creation.
+                self.state = HKWMentionsCreationStateQuiescent;
+                [delegate cancelMentionFromStartingLocation:self.startingLocation];
+                return;
+            }
+
             if (deleteStringIsTransient) {
                 // Delete was typed, but for some sort of transient state (e.g. keyboard suggestions); don't do anything
                 return;

diff --git a/Hakawai/Mentions/HKWMentionsPlugin.m b/Hakawai/Mentions/HKWMentionsPlugin.m
@@ -845,15 +845,23 @@ - (BOOL)advanceStateForCharacterInsertion:(unichar)newChar
     BOOL isSecondSpace = (location > 1) && (precedingChar == ' ' && newChar == ' ');
     switch (self.state) {
         case HKWMentionsStateQuiescent: {
+            // Word following typed character would be used to trigger matching mentions menu when possible.
+            NSString *wordFollowingTypedCharacter;
             if (HKWTextView.enableKoreanMentionsFix) {
                 // Update the location of the selected range for this insertion here
                 // (since the text view will already be updated when utilizing the text storage delegate in the korean mentions fix)
                 // This should replace other settings of this range when the fix is ramped
                 parentTextView.selectedRange = NSMakeRange(location, parentTextView.selectedRange.length);
+                wordFollowingTypedCharacter = [HKWMentionsStartDetectionStateMachine wordAfterLocation:location text:parentTextView.textStateBeforeDeletion];
+            } else {
+                wordFollowingTypedCharacter = [HKWMentionsStartDetectionStateMachine wordAfterLocation:location text:parentTextView.text];
             }
             // Inform the start detection state machine that a character was inserted. Also, override the double space
             //  to period auto-substitution if the substitution would place a period right after a preceding mention.
-            [self.startDetectionStateMachine characterTyped:newChar asInsertedCharacter:NO previousCharacter:precedingChar];
+            [self.startDetectionStateMachine characterTyped:newChar
+                                        asInsertedCharacter:NO
+                                          previousCharacter:precedingChar
+                                wordFollowingTypedCharacter:wordFollowingTypedCharacter];
             NSRange r;
             id mentionTwoPreceding = [self mentionAttributePrecedingLocation:(location-1) range:&r];
             BOOL shouldSuppress = (mentionTwoPreceding != nil) && (r.location + r.length == location-1);
@@ -879,7 +887,10 @@ - (BOOL)advanceStateForCharacterInsertion:(unichar)newChar
             //  insert a new character and continue in the quiescent state. Do not allow auto-substitution.
             self.state = HKWMentionsStateQuiescent;
             [self resetCurrentMentionsData];
-            [self.startDetectionStateMachine characterTyped:newChar asInsertedCharacter:NO previousCharacter:precedingChar];
+            [self.startDetectionStateMachine characterTyped:newChar
+                                        asInsertedCharacter:NO
+                                          previousCharacter:precedingChar
+                                wordFollowingTypedCharacter:nil];
             if (isSecondSpace) {
                 [self manuallyInsertCharacter:newChar atLocation:location inTextView:parentTextView];
                 self.characterForAdvanceStateForCharacterInsertion = (unichar)0;
@@ -901,7 +912,7 @@ - (BOOL)advanceStateForCharacterInsertion:(unichar)newChar
             [self resetCurrentMentionsData];
             self.state = HKWMentionsStateQuiescent;
             self.characterForAdvanceStateForCharacterInsertion = (unichar)0;
-            [self.startDetectionStateMachine characterTyped:newChar asInsertedCharacter:YES previousCharacter:precedingChar];
+            [self.startDetectionStateMachine characterTyped:newChar asInsertedCharacter:YES previousCharacter:precedingChar wordFollowingTypedCharacter:nil];
             returnValue = NO;
             break;
         case HKWMentionsStateLosingFocus:
@@ -932,7 +943,9 @@ - (BOOL)advanceStateForCharacterDeletion:(unichar)precedingChar
     switch (self.state) {
         case HKWMentionsStateQuiescent: {
             [self.startDetectionStateMachine deleteTypedCharacter:deletedChar
-                                  withCharacterNowPrecedingCursor:precedingChar];
+                                  withCharacterNowPrecedingCursor:precedingChar
+                                                         location:location
+                                                     textViewText:parentTextView.text];
             self.nextSelectionChangeShouldBeIgnored = YES;
 
             // Look for a mention
@@ -1144,8 +1157,10 @@ - (BOOL)advanceStateForStringInsertionAtRange:(NSRange)range text:(NSString *)te
                 self.previousSelectionRange = newSelectionRange;
                 self.previousTextLength = [[parentTextView text] length];
 
-                [self.startDetectionStateMachine characterTyped:[text characterAtIndex:0] asInsertedCharacter:YES previousCharacter:precedingChar];
-
+                [self.startDetectionStateMachine characterTyped:[text characterAtIndex:0]
+                                            asInsertedCharacter:YES
+                                              previousCharacter:precedingChar
+                                    wordFollowingTypedCharacter:nil];
                 // Manually notify external delegate that the textView changed
                 id<HKWTextViewDelegate> externalDelegate = parentTextView.externalDelegate;
                 if ([externalDelegate respondsToSelector:@selector(textViewDidChange:)]) {
@@ -1932,7 +1947,12 @@ - (void)createMention:(HKWMentionsAttribute *)mention startingLocation:(NSUInteg
     UIColor *parentColor = parentTextView.textColorSetByApp;
     NSAssert(self.mentionUnselectedAttributes != nil, @"Error! Mention attribute dictionaries should never be nil.");
     NSDictionary *unselectedAttributes = self.mentionUnselectedAttributes;
-    NSRange rangeToTransform = NSMakeRange(location, currentLocation - location);
+
+    // When control character is inserted before word and user selects mention for that word,
+    // we want to replace word after control character with mention text.
+    // e.g "hey @|john" will be replaced as "hey John Doe". '|' indicates cursor.
+    NSString *const wordAfterCurrentLocation = [HKWMentionsStartDetectionStateMachine wordAfterLocation:currentLocation text:parentTextView.text];
+    NSRange rangeToTransform = NSMakeRange(location, currentLocation + wordAfterCurrentLocation.length - location);
 
     /*
      When the textview text that matches the mention text is not the first part of the mention text,