Set up testing and write tests for blocks reducer

.eslintrc.json

@@ -2,7 +2,8 @@
   "env": {
     "browser": true,
     "es2021": true,
-    "node": true
+    "node": true,
+    "jest": true
   },
   "extends": ["eslint:recommended", "plugin:react/recommended"],
   "parser": "babel-eslint",

.gitignore

@@ -1,3 +1,5 @@
 /node_modules
 /release-builds
 /dist
+/coverage
+/tools

__tests__/blocksReducer/createPiece.js

@@ -0,0 +1,45 @@
+import blocksReducer from "../../src/reducers/blocksReducer";
+import { NEW_PIECE } from "../../src/actions/types";
+import {
+  L_PIECE_1,
+  T_PIECE,
+  L_PIECE_2,
+  S_PIECE,
+  Z_PIECE_1,
+  Z_PIECE_2,
+  B_PIECE,
+} from "../../src/reducers/blocksReducer/pieces";
+import { createState } from "./utils";
+
+const pieces = [
+  L_PIECE_1,
+  T_PIECE,
+  L_PIECE_2,
+  S_PIECE,
+  Z_PIECE_1,
+  Z_PIECE_2,
+  B_PIECE,
+];
+
+describe("blocks reducer", () => {
+  const state = createState();
+  const newState = blocksReducer(state, { type: NEW_PIECE });
+
+  it("should create valid current piece", () => {
+    // The new piece created must match one of the pieces.
+    const index = pieces.findIndex(
+      (piece) => piece.type === newState.currentPiece.type
+    );
+    expect(index).not.toBe(-1);
+    expect(newState.currentPiece).toEqual(pieces[index]);
+  });
+
+  it("should create valid next piece", () => {
+    // The new piece created must match one of the pieces.
+    const index = pieces.findIndex(
+      (piece) => piece.type === newState.nextPiece.type
+    );
+    expect(index).not.toBe(-1);
+    expect(newState.nextPiece).toEqual(pieces[index]);
+  });
+});

__tests__/blocksReducer/movement/combine.js

@@ -0,0 +1,64 @@
+import { L_PIECE_1 } from "../../../src/reducers/blocksReducer/pieces";
+import {
+  LEFT_KEYCODE,
+  RIGHT_KEYCODE,
+  DOWN_KEYCODE,
+} from "../../../src/utils/constants";
+import { createState, moveCurrentPiece } from "../utils";
+
+describe("Can move piece and combine with floor", () => {
+  it("L_PIECE_1", () => {
+    let state = createState(L_PIECE_1);
+    // Must bring L piece closer to landed blocks
+    state = moveCurrentPiece(state, [DOWN_KEYCODE], 19);
+    // Current piece is removed when combined with floor
+    expect(state.currentPiece).toEqual({ blocks: [] });
+    expect(state.blocks).toEqual({
+      15: { 4: 0 },
+      16: { 4: 0 },
+      17: { 3: 0, 4: 0 },
+    });
+  });
+});
+
+describe("Can move piece and combine with landed blocks", () => {
+  // Landed L_PIECE_1
+  const landedBlocks = {
+    15: { 4: 0 },
+    16: { 4: 0 },
+    17: { 3: 0, 4: 0 },
+  };
+  // Ignore
+  const nextPiece = { blocks: [] };
+
+  it("L_PIECE_1 single direction", () => {
+    let state = createState(L_PIECE_1, nextPiece, landedBlocks);
+    // Must bring L piece closer to landed blocks
+    state = moveCurrentPiece(state, [DOWN_KEYCODE], 16);
+    // Current piece is removed when combined with landed blocks
+    expect(state.currentPiece).toEqual({ blocks: [] });
+    expect(state.blocks).toEqual({
+      12: { 4: 0 },
+      13: { 4: 0 },
+      14: { 3: 0, 4: 0 },
+      15: { 4: 0 },
+      16: { 4: 0 },
+      17: { 3: 0, 4: 0 },
+    });
+  });
+
+  it("L_PIECE_1 two directions", () => {
+    let state = createState(L_PIECE_1, nextPiece, landedBlocks);
+    state = moveCurrentPiece(state, [LEFT_KEYCODE], 2);
+    state = moveCurrentPiece(state, [DOWN_KEYCODE], 16);
+    // Now move in 2 directions
+    state = moveCurrentPiece(state, [RIGHT_KEYCODE, DOWN_KEYCODE], 2);
+    expect(state.currentPiece).toEqual({ blocks: [] });
+    expect(state.blocks).toEqual({
+      14: { 3: 0 },
+      15: { 3: 0, 4: 0 },
+      16: { 2: 0, 3: 0, 4: 0 },
+      17: { 3: 0, 4: 0 },
+    });
+  });
+});

__tests__/blocksReducer/movement/noMoveIntoWalls.js

@@ -0,0 +1,25 @@
+import { L_PIECE_1 } from "../../../src/reducers/blocksReducer/pieces";
+import { LEFT_KEYCODE, RIGHT_KEYCODE } from "../../../src/utils/constants";
+import { createState, moveCurrentPiece } from "../utils";
+
+describe("Cannot move into walls", () => {
+  it("L_PIECE_1", () => {
+    let state = createState(L_PIECE_1);
+    state = moveCurrentPiece(state, [LEFT_KEYCODE], 10);
+    // Cannot move into left wall
+    expect(state.currentPiece.blocks).toEqual([
+      { x: -1, y: 0, color: 0, type: 0 },
+      { x: -1, y: 1, color: 0, type: 1 },
+      { x: -2, y: 1, color: 0, type: 2 },
+      { x: -3, y: 1, color: 0, type: 1 },
+    ]);
+    state = moveCurrentPiece(state, [RIGHT_KEYCODE], 10);
+    // Cannot move into right wall
+    expect(state.currentPiece.blocks).toEqual([
+      { x: -1, y: 8, color: 0, type: 0 },
+      { x: -1, y: 9, color: 0, type: 1 },
+      { x: -2, y: 9, color: 0, type: 2 },
+      { x: -3, y: 9, color: 0, type: 1 },
+    ]);
+  });
+});