fix(pagination): ensure page never drops below first page

Closes: #182

src/components/Pagination.vue

@@ -87,7 +87,11 @@ export default {
   },
   methods: {
     goToPage(page) {
-      this.searchStore.page = Math.min(this.totalPages, page);
+      let p = page;
+      if (page <= 1) {
+        p = 1;
+      }
+      this.searchStore.page = Math.min(this.totalPages, p);
     },
     goToFirstPage() {
       this.goToPage(1);

src/components/__tests__/pagination.js

@@ -2,11 +2,9 @@ import Vue from 'vue';
 import { Pagination } from 'vue-instantsearch';
 
 test('renders proper HTML', () => {
-  const goToPage = jest.fn();
   const searchStore = {
     page: 2,
     totalPages: 10,
-    goToPage,
   };
   const Component = Vue.extend(Pagination);
   const vm = new Component({
@@ -20,11 +18,9 @@ test('renders proper HTML', () => {
 });
 
 test('accepts custom padding', () => {
-  const goToPage = jest.fn();
   const searchStore = {
     page: 5,
     totalPages: 10,
-    goToPage,
   };
   const Component = Vue.extend(Pagination);
   const vm = new Component({
@@ -37,3 +33,37 @@ test('accepts custom padding', () => {
 
   expect(vm.$el.outerHTML).toMatchSnapshot();
 });
+
+test('it should not try to go to a previous page that would be inferior to 1', () => {
+  const searchStore = {
+    page: 1,
+    totalPages: 20,
+  };
+  const Component = Vue.extend(Pagination);
+  const vm = new Component({
+    propsData: {
+      searchStore,
+    },
+  });
+
+  vm.goToPreviousPage();
+
+  expect(searchStore.page).toEqual(1);
+});
+
+test('it should not try to go to a next page that would be superior to total existing pages', () => {
+  const searchStore = {
+    page: 20,
+    totalPages: 20,
+  };
+  const Component = Vue.extend(Pagination);
+  const vm = new Component({
+    propsData: {
+      searchStore,
+    },
+  });
+
+  vm.goToNextPage();
+
+  expect(searchStore.page).toEqual(20);
+});