Stack

hojas · hojas · commit ceaa8817ed31 · 2024-01-14T19:11:06.000+08:00
diff --git a/src/data-structures/stack/Stack.test.ts b/src/data-structures/stack/Stack.test.ts
@@ -0,0 +1,83 @@
+import { describe, expect, it } from 'vitest'
+import { Stack } from './Stack'
+
+describe('stack', () => {
+  it('should create empty stack', () => {
+    const stack = new Stack()
+
+    expect(stack.size()).toBe(0)
+    expect(stack.isEmpty()).toBe(true)
+  })
+
+  it('should push items to stack', () => {
+    const stack = new Stack()
+
+    stack.push(1)
+    expect(stack.size()).toBe(1)
+    expect(stack.isEmpty()).toBe(false)
+    expect(stack.toString()).toBe('1')
+
+    stack.push(2)
+    expect(stack.size()).toBe(2)
+    expect(stack.isEmpty()).toBe(false)
+    expect(stack.toString()).toBe('2,1')
+  })
+
+  it('should pop items from stack', () => {
+    const stack = new Stack()
+
+    stack.push(1)
+    stack.push(2)
+
+    expect(stack.pop()).toBe(2)
+    expect(stack.size()).toBe(1)
+    expect(stack.pop()).toBe(1)
+    expect(stack.size()).toBe(0)
+    expect(stack.pop()).toBe(undefined)
+    expect(stack.isEmpty()).toBe(true)
+  })
+
+  it('should peek data from stack', () => {
+    const stack = new Stack()
+
+    expect(stack.peek()).toBe(undefined)
+
+    stack.push(1)
+    stack.push(2)
+
+    expect(stack.peek()).toBe(2)
+    expect(stack.size()).toBe(2)
+  })
+
+  it('should check if stack is empty', () => {
+    const stack = new Stack()
+
+    expect(stack.isEmpty()).toBe(true)
+
+    stack.push(1)
+    expect(stack.isEmpty()).toBe(false)
+  })
+
+  it('should clear the stack', () => {
+    const stack = new Stack()
+
+    stack.push(1)
+    stack.push(2)
+
+    stack.clear()
+    expect(stack.isEmpty()).toBe(true)
+    expect(stack.size()).toBe(0)
+  })
+
+  it('should be possible to push/pop objects', () => {
+    const stack = new Stack()
+
+    stack.push({ value: 'test1', key: 'key1' })
+    stack.push({ value: 'test2', key: 'key2' })
+
+    const stringifier = (value: any) => `${value.key}:${value.value}`
+    expect(stack.toString(stringifier)).toBe('key2:test2,key1:test1')
+    expect(stack.pop().value).toBe('test2')
+    expect(stack.pop().value).toBe('test1')
+  })
+})
diff --git a/src/data-structures/stack/Stack.ts b/src/data-structures/stack/Stack.ts
@@ -0,0 +1,34 @@
+export class Stack {
+  private items: any[] = []
+
+  push(item: any) {
+    this.items.push(item)
+  }
+
+  pop() {
+    return this.items.pop()
+  }
+
+  peek() {
+    return this.items[this.items.length - 1]
+  }
+
+  isEmpty() {
+    return this.items.length === 0
+  }
+
+  size() {
+    return this.items.length
+  }
+
+  clear() {
+    this.items = []
+  }
+
+  toString(callback?: (item: any) => string) {
+    const list = this.items.toReversed()
+    if (callback)
+      return list.map(callback).toString()
+    return list.toString()
+  }
+}
diff --git a/tsconfig.json b/tsconfig.json
@@ -1,23 +1,19 @@
 {
   "compilerOptions": {
-    "target": "ES2020",
+    "target": "ES2015",
+    "lib": ["ES2023", "DOM", "DOM.Iterable"],
     "useDefineForClassFields": true,
     "module": "ESNext",
-    "lib": ["ES2020", "DOM", "DOM.Iterable"],
-    "skipLibCheck": true,
-
-    /* Bundler mode */
     "moduleResolution": "bundler",
-    "allowImportingTsExtensions": true,
     "resolveJsonModule": true,
-    "isolatedModules": true,
-    "noEmit": true,
-
-    /* Linting */
+    "allowImportingTsExtensions": true,
     "strict": true,
+    "noFallthroughCasesInSwitch": true,
     "noUnusedLocals": true,
     "noUnusedParameters": true,
-    "noFallthroughCasesInSwitch": true
+    "noEmit": true,
+    "isolatedModules": true,
+    "skipLibCheck": true
   },
   "include": ["src"]
 }
