should find pivot in next selection after adjacent

Author: codingedgar

package.json

@@ -1,6 +1,6 @@
 {
   "name": "macos-multi-select",
-  "version": "0.1.0",
+  "version": "0.1.1",
   "description": "Given a list of ids, and an action, return a list of selected items with the same behaviour of macOS finder list view selection.",
   "main": "dist/index.js",
   "repository": "[email protected]:codingedgar/macos-multi-select.git",

src/index.ts

@@ -49,7 +49,7 @@ export function multiselect(context: Context, command: Command): Context {
     const adjacentPivot = findNextPivot(
       context.list,
       selected,
-      context.adjacentPivot
+      command.id
     );
 
     return {

src/spec/arrayUtils.spec.ts

@@ -168,17 +168,17 @@ describe('find next pivot', () => {
         .chain(sortedArray =>
           fc
             .nat(sortedArray.length - 2)
-            .chain(index =>
+            .chain(previousPivot =>
               fc
-                .integer(index + 1, sortedArray.length -1)
+                .integer(previousPivot + 1, sortedArray.length - 1)
                 .chain(nextPivot =>
                   fc.
                     tuple(
-                      fc.shuffledSubarray(sortedArray.slice(0, index)),
-                      fc.shuffledSubarray(sortedArray.slice(nextPivot +1, sortedArray.length - 1))
+                      fc.shuffledSubarray(sortedArray.slice(0, previousPivot)),
+                      fc.shuffledSubarray(sortedArray.slice(nextPivot + 1, sortedArray.length - 1))
                     )
                     .map(([left, right]) => ({
-                        previousPivot: sortedArray[index],
+                        previousPivot: sortedArray[previousPivot],
                         sortedArray: sortedArray,
                         nextPivot: sortedArray[nextPivot],
                         selection: left.concat([sortedArray[nextPivot]]).concat(right)

src/spec/toggleSelection.spec.ts

@@ -71,4 +71,69 @@ describe('Toggle Selection', () => {
       )
     )
   });
+
+
+  test('should find pivot in next selection even when pivot is in the initial state due to select adjacent on initial state', () => {
+    fc.assert(
+      fc.property(
+        fc.set(
+          fc.string(),
+          { minLength: 2 }
+        )
+        .chain(sortedArray =>
+          fc
+            .nat(sortedArray.length -2)
+            .chain(previousSelection => 
+              fc
+                .integer(previousSelection + 1, sortedArray.length - 1)
+                .chain(nextPivot =>
+                  fc.
+                    tuple(
+                      fc.constant(sortedArray.slice(0, previousSelection)),
+                      fc.shuffledSubarray(sortedArray.slice(nextPivot + 1, sortedArray.length - 1))
+                    )
+                    .map(([left, right]) => ({
+                        sortedArray: sortedArray,
+                        previousPivot: head(sortedArray)!,
+                        prevSelection: left
+                          .concat([sortedArray[previousSelection]])
+                          .concat([sortedArray[nextPivot]])
+                          .concat(right),
+                        deselectId: sortedArray[previousSelection],
+                        nextPivot: sortedArray[nextPivot],
+                        nextSelection: left
+                          .concat([sortedArray[nextPivot]])
+                          .concat(right),
+                    }))
+                ),
+            ),
+        )
+        ,
+        ({
+          previousPivot,
+          sortedArray,
+          prevSelection,
+          nextSelection,
+          nextPivot,
+          deselectId
+        }) => {
+          expect(
+            multiselect({
+              adjacentPivot: previousPivot,
+              list: sortedArray,
+              selected: prevSelection
+            }, {
+              type: "TOGGLE SELECTION",
+              id: deselectId
+            }
+          )
+          ).toEqual({
+            list: sortedArray,
+            adjacentPivot: nextPivot,
+            selected: nextSelection
+          })
+        }
+      )
+    )
+  })
 })