Fix triple selection extending to next block (#1605)

* Fix triple selection extending to next block

* Remove unused startOffset

* Add Iscollapsed check to prevent failing setBlock on initial block position

* Fix across-blocks.js test

* Test new hanging selection behaviour

* Lint

* Revert e902fa1acb

* Lint

* Use ternary operator instead of if/else

packages/slate/src/changes/at-range.js

@@ -948,7 +948,26 @@ Changes.setBlockAtRange = (change, range, properties, options = {}) => {
   const { document } = value
   const blocks = document.getBlocksAtRange(range)
 
-  blocks.forEach(block => {
+  const { startKey, startOffset, endKey, endOffset, isCollapsed } = range
+  const isStartVoid = document.hasVoidParent(startKey)
+  const startBlock = document.getClosestBlock(startKey)
+  const endBlock = document.getClosestBlock(endKey)
+
+  // Check if we have a "hanging" selection case where the even though the
+  // selection extends into the start of the end node, we actually want to
+  // ignore that for UX reasons.
+  const isHanging =
+    isCollapsed == false &&
+    startOffset == 0 &&
+    endOffset == 0 &&
+    isStartVoid == false &&
+    startKey == startBlock.getFirstText().key &&
+    endKey == endBlock.getFirstText().key
+
+  // If it's a hanging selection, ignore the last block.
+  const sets = isHanging ? blocks.slice(0, -1) : blocks
+
+  sets.forEach(block => {
     change.setNodeByKey(block.key, properties, { normalize })
   })
 }

packages/slate/test/changes/at-current-range/set-block/across-blocks.js

@@ -13,7 +13,7 @@ export const input = (
         <anchor />word
       </paragraph>
       <paragraph>
-        <focus />another
+        a<focus />nother
       </paragraph>
     </document>
   </value>
@@ -26,7 +26,7 @@ export const output = (
         <anchor />word
       </code>
       <code>
-        <focus />another
+        a<focus />nother
       </code>
     </document>
   </value>

packages/slate/test/changes/at-current-range/set-block/hanging-selection.js

@@ -0,0 +1,33 @@
+/** @jsx h */
+
+import h from '../../../helpers/h'
+
+export default function(change) {
+  change.setBlock({ type: 'code' })
+}
+
+export const input = (
+  <value>
+    <document>
+      <paragraph>
+        <anchor />word
+      </paragraph>
+      <paragraph>
+        <focus />another
+      </paragraph>
+    </document>
+  </value>
+)
+
+export const output = (
+  <value>
+    <document>
+      <code>
+        <anchor />word
+      </code>
+      <paragraph>
+        <focus />another
+      </paragraph>
+    </document>
+  </value>
+)