toggle selection #2

Author: codingedgar

package.json

@@ -1,6 +1,6 @@
 {
   "name": "macos-multi-select",
-  "version": "0.0.1",
+  "version": "0.0.2",
   "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

@@ -1,17 +1,35 @@
-type Context = {
+export type Context = {
   list: string[],
   selected: string[],
 }
 
 type Command =
-  | {type: "SINGLE SELECT", id: string}
+  | { type: "SELECT ONE", id: string }
+  | { type: "TOGGLE SELECTION", id: string }
 
 export function multiselect(context: Context, command: Command): Context {
-  if (command.type === 'SINGLE SELECT' && context.list.includes(command.id)) {
+  if (command.type === "SELECT ONE" && context.list.includes(command.id)) {
     return {
       ...context,
       selected: [command.id]
     };
+  } else if (
+      command.type === 'TOGGLE SELECTION' &&
+      context.list.includes(command.id) &&
+      context.selected.includes(command.id)
+    ) {
+    return {
+      ...context,
+      selected: context.selected.filter(x => x !== command.id),
+    };
+  } else if (
+      command.type === 'TOGGLE SELECTION' &&
+      context.list.includes(command.id)
+    ) {
+    return {
+      ...context,
+      selected: context.selected.concat([command.id])
+    };
   } else {
     return context;
   }

src/spec/selectAnItem.spec.ts renamed to src/spec/selectOne.ts

@@ -1,5 +1,6 @@
 import fc from 'fast-check';
-import {multiselect} from '../index';
+import { multiselect } from '../index';
+
 describe('Select an Item', () => {
   test('should be able to select one item in a non empty list', () => {
 
@@ -26,7 +27,7 @@ describe('Select an Item', () => {
                   selected: [],
                 },
                 {
-                  type: 'SINGLE SELECT',
+                  type: "SELECT ONE",
                   id,
                 }
               )
@@ -69,7 +70,7 @@ describe('Select an Item', () => {
                   selected: [selectedId],
                 },
                 {
-                  type: 'SINGLE SELECT',
+                  type: "SELECT ONE",
                   id,
                 }
               )

src/spec/toggleSelection.spec.ts

@@ -0,0 +1,52 @@
+import fc from 'fast-check';
+import { multiselect, Context } from '../index';
+
+describe('TOGGLE SELECTION', () => {
+  test('should be able to add to selection one item in a non empty list', () => {
+
+    fc.assert(
+      fc.property(
+        fc.set(
+          fc.string()
+        )
+        .filter(list => list.length > 0)
+        .chain(list =>
+          fc.record({
+            list: fc.constant(list),
+            toSelect: fc.set(
+              fc.integer(0, list.length-1)
+              .map(index => list[index]),
+            ),
+          })  
+        ),
+          ({
+            list,
+            toSelect,
+          }) => {
+
+            expect(
+              toSelect.reduce(
+                (context: Context, id) =>
+                  multiselect(
+                    context,
+                    {
+                      type: "TOGGLE SELECTION",
+                      id,
+                    }
+                  ),
+                  {
+                    list,
+                    selected: []
+                  }
+                )
+            )
+              .toEqual({
+                list,
+                selected: toSelect
+              })
+          }
+        )
+    )
+
+  });
+})