test: add unit tests for CommandHistory functionality

packages/core/src/history/CommandHistory.test.ts

@@ -0,0 +1,186 @@
+// ─────────────────────────────────────────────────────
+// @termuijs/core — Tests for CommandHistory
+// ─────────────────────────────────────────────────────
+
+import { describe, it, expect } from 'vitest';
+import { CommandHistory } from './CommandHistory.js';
+
+describe('CommandHistory', () => {
+
+    // ── constructor ──────────────────────────────────
+
+    it('defaults maxSize to 100', () => {
+        const ch = new CommandHistory();
+        for (let i = 0; i < 101; i++) ch.add(`cmd${i}`);
+        expect(ch.getAll()).toHaveLength(100);
+    });
+
+    it('respects custom maxSize', () => {
+        const ch = new CommandHistory({ maxSize: 3 });
+        ch.add('a');
+        ch.add('b');
+        ch.add('c');
+        ch.add('d'); // evicts 'a'
+        expect(ch.getAll()).toEqual(['b', 'c', 'd']);
+    });
+
+    // ── add ──────────────────────────────────────────
+
+    it('add() stores a valid command', () => {
+        const ch = new CommandHistory();
+        ch.add('ls -la');
+        expect(ch.getAll()).toContain('ls -la');
+    });
+
+    it('add() ignores empty string', () => {
+        const ch = new CommandHistory();
+        ch.add('');
+        expect(ch.getAll()).toHaveLength(0);
+    });
+
+    it('add() ignores whitespace-only string', () => {
+        const ch = new CommandHistory();
+        ch.add('   ');
+        expect(ch.getAll()).toHaveLength(0);
+    });
+
+    it('add() evicts oldest command when maxSize exceeded', () => {
+        const ch = new CommandHistory({ maxSize: 2 });
+        ch.add('first');
+        ch.add('second');
+        ch.add('third'); // evicts 'first'
+        expect(ch.getAll()).not.toContain('first');
+        expect(ch.getAll()).toContain('third');
+    });
+
+    // ── previous ─────────────────────────────────────
+
+    it('previous() returns null when history is empty', () => {
+        const ch = new CommandHistory();
+        expect(ch.previous()).toBeNull();
+    });
+
+    it('previous() returns last command first', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd1');
+        ch.add('cmd2');
+        expect(ch.previous()).toBe('cmd2');
+    });
+
+    it('previous() navigates backward through history', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd1');
+        ch.add('cmd2');
+        ch.previous(); // cmd2
+        expect(ch.previous()).toBe('cmd1');
+    });
+
+    it('previous() clamps at the first command', () => {
+        const ch = new CommandHistory();
+        ch.add('only');
+        ch.previous();
+        ch.previous(); // should stay at 'only'
+        expect(ch.previous()).toBe('only');
+    });
+
+    // ── next ─────────────────────────────────────────
+
+    it('next() returns null when history is empty', () => {
+        const ch = new CommandHistory();
+        expect(ch.next()).toBeNull();
+    });
+
+    it('next() returns null when past the last command', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd1');
+        ch.previous(); // go back
+        ch.next();     // go forward to end
+        expect(ch.next()).toBeNull();
+    });
+
+    it('next() navigates forward after going back', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd1');
+        ch.add('cmd2');
+        ch.previous(); // cmd2
+        ch.previous(); // cmd1
+        expect(ch.next()).toBe('cmd2');
+    });
+
+    // ── search ───────────────────────────────────────
+
+    it('search() returns matching commands', () => {
+        const ch = new CommandHistory();
+        ch.add('git status');
+        ch.add('git commit');
+        ch.add('ls -la');
+        expect(ch.search('git')).toEqual(['git status', 'git commit']);
+    });
+
+    it('search() is case-insensitive', () => {
+    const ch = new CommandHistory();
+    ch.add('Git Status');
+    expect(ch.search('git')).toEqual(['Git Status']);
+});
+
+    it('search() returns empty array when no match', () => {
+        const ch = new CommandHistory();
+        ch.add('ls -la');
+        expect(ch.search('nonexistent')).toEqual([]);
+    });
+
+    // ── getAll ───────────────────────────────────────
+
+    it('getAll() returns all commands in order', () => {
+        const ch = new CommandHistory();
+        ch.add('first');
+        ch.add('second');
+        expect(ch.getAll()).toEqual(['first', 'second']);
+    });
+
+    it('getAll() returns a copy not the internal array', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd');
+        const all = ch.getAll();
+        all.push('injected');
+        expect(ch.getAll()).toHaveLength(1);
+    });
+
+    // ── clear ────────────────────────────────────────
+
+    it('clear() empties history', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd1');
+        ch.add('cmd2');
+        ch.clear();
+        expect(ch.getAll()).toHaveLength(0);
+    });
+
+    it('clear() resets navigation so previous() returns null', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd1');
+        ch.clear();
+        expect(ch.previous()).toBeNull();
+    });
+
+    // ── export / import ──────────────────────────────
+
+    it('export() serializes history to JSON string', () => {
+        const ch = new CommandHistory();
+        ch.add('cmd1');
+        ch.add('cmd2');
+        expect(ch.export()).toBe(JSON.stringify(['cmd1', 'cmd2']));
+    });
+
+    it('import() restores history from JSON string', () => {
+        const ch = new CommandHistory();
+        ch.import(JSON.stringify(['cmd1', 'cmd2']));
+        expect(ch.getAll()).toEqual(['cmd1', 'cmd2']);
+    });
+
+    it('import() allows navigation after restore', () => {
+        const ch = new CommandHistory();
+        ch.import(JSON.stringify(['cmd1', 'cmd2']));
+        expect(ch.previous()).toBe('cmd2');
+    });
+});