Merge branch 'fix-focus-html5-inputs'

1 files changed, 21 insertions, 10 deletions

diff --git a/lib/dom_utils.coffee b/lib/dom_utils.coffee
index f53e28d1..0231f994 100644
--- a/lib/dom_utils.coffee
+++ b/lib/dom_utils.coffee
@@ -167,15 +167,20 @@ DomUtils =
       node = node.parentNode
     false
 
-  # True if element contains the active selection range.
+  # True if element is editable and contains the active selection range.
   isSelected: (element) ->
+    selection = document.getSelection()
     if element.isContentEditable
-      node = document.getSelection()?.anchorNode
+      node = selection.anchorNode
       node and @isDOMDescendant element, node
     else
-      # Note.  This makes the wrong decision if the user has placed the caret at the start of element.  We
-      # cannot distinguish that case from the user having made no selection.
-      element.selectionStart? and element.selectionEnd? and element.selectionEnd != 0
+      if selection.type == "Range" and selection.isCollapsed
+	      # The selection is inside the Shadow DOM of a node. We can check the node it registers as being
+	      # before, since this represents the node whose Shadow DOM it's inside.
+        containerNode = selection.anchorNode.childNodes[selection.anchorOffset]
+        element == containerNode # True if the selection is inside the Shadow DOM of our element.
+      else
+        false
 
   simulateSelect: (element) ->
     # If element is already active, then we don't move the selection.  However, we also won't get a new focus
@@ -185,11 +190,17 @@ DomUtils =
       handlerStack.bubbleEvent "click", target: element
     else
       element.focus()
-      unless @isSelected element
-        # When focusing a textbox (without an existing selection), put the selection caret at the end of the
-        # textbox's contents.  For some HTML5 input types (eg. date) we can't position the caret, so we wrap
-        # this with a try.
-        try element.setSelectionRange(element.value.length, element.value.length)
+      # If the cursor is at the start of the element's contents, send it to the end. Motivation:
+      # * the end is a more useful place to focus than the start,
+      # * this way preserves the last used position (except when it's at the beginning), so the user can
+      #   'resume where they left off'.
+      # NOTE(mrmr1993): Some elements throw an error when we try to access their selection properties, so
+      # wrap this with a try.
+      try
+        if element.selectionStart == 0 and element.selectionEnd == 0
+          element.setSelectionRange element.value.length, element.value.length
+
+
 
   simulateClick: (element, modifiers) ->
     modifiers ||= {}