add getrange command (stipsan#165)

* added badge to compat table for easy overview

* fix messed up render

* add title

* add getrange command

compat.md

@@ -1,11 +1,11 @@
+## Supported commands ![Commands Coverage: 29%](https://img.shields.io/badge/coverage-29%25-orange.svg)
 
-### Supported commands
 | redis | ioredis | ioredis-mock |
 |-------|:-------:|:------------:|
 |[append](http://redis.io/commands/APPEND)|:white_check_mark:|:white_check_mark:|
-|[auth](http://redis.io/commands/AUTH)|:white_check_mark:|:x:|
-|[bgrewriteaof](http://redis.io/commands/BGREWRITEAOF)|:white_check_mark:|:x:|
-|[bgsave](http://redis.io/commands/BGSAVE)|:white_check_mark:|:x:|
+|[auth](http://redis.io/commands/AUTH)|:white_check_mark:|:white_check_mark:|
+|[bgrewriteaof](http://redis.io/commands/BGREWRITEAOF)|:white_check_mark:|:white_check_mark:|
+|[bgsave](http://redis.io/commands/BGSAVE)|:white_check_mark:|:white_check_mark:|
 |[bitcount](http://redis.io/commands/BITCOUNT)|:white_check_mark:|:x:|
 |[bitfield](http://redis.io/commands/BITFIELD)|:white_check_mark:|:x:|
 |[bitop](http://redis.io/commands/BITOP)|:white_check_mark:|:x:|
@@ -62,7 +62,7 @@
 |[incrbyfloat](http://redis.io/commands/INCRBYFLOAT)|:white_check_mark:|:x:|
 |[info](http://redis.io/commands/INFO)|:white_check_mark:|:x:|
 |[keys](http://redis.io/commands/KEYS)|:white_check_mark:|:white_check_mark:|
-|[lastsave](http://redis.io/commands/LASTSAVE)|:white_check_mark:|:x:|
+|[lastsave](http://redis.io/commands/LASTSAVE)|:white_check_mark:|:white_check_mark:|
 |[lindex](http://redis.io/commands/LINDEX)|:white_check_mark:|:x:|
 |[linsert](http://redis.io/commands/LINSERT)|:white_check_mark:|:x:|
 |[llen](http://redis.io/commands/LLEN)|:white_check_mark:|:white_check_mark:|
@@ -107,7 +107,7 @@
 |[rpush](http://redis.io/commands/RPUSH)|:white_check_mark:|:white_check_mark:|
 |[rpushx](http://redis.io/commands/RPUSHX)|:white_check_mark:|:x:|
 |[sadd](http://redis.io/commands/SADD)|:white_check_mark:|:white_check_mark:|
-|[save](http://redis.io/commands/SAVE)|:white_check_mark:|:x:|
+|[save](http://redis.io/commands/SAVE)|:white_check_mark:|:white_check_mark:|
 |[scan](http://redis.io/commands/SCAN)|:white_check_mark:|:x:|
 |[scard](http://redis.io/commands/SCARD)|:white_check_mark:|:x:|
 |[script](http://redis.io/commands/SCRIPT)|:white_check_mark:|:x:|

scripts/update-compat.js

@@ -21,18 +21,44 @@ const blacklist = [
 ];
 const filteredCommands = commands.list.filter(command => blacklist.indexOf(command) === -1);
 
-let tableMd = `
-### Supported commands
+let supportedCommands = 0;
+let tableRows = `
 | redis | ioredis | ioredis-mock |
 |-------|:-------:|:------------:|`;
 filteredCommands.forEach((command) => {
   const redisCol = `[${command}](http://redis.io/commands/${command.toUpperCase()})`;
   const ioredisCol = command in redis.prototype ? ':white_check_mark:' : ':x:';
-  const ioredisMockCol = command in mockedRedis ? ':white_check_mark:' : ':x:';
-  tableMd += `
+  const supportedCommand = command in mockedRedis;
+  const ioredisMockCol = supportedCommand ? ':white_check_mark:' : ':x:';
+  if (supportedCommand) {
+    supportedCommands += 1;
+  }
+  tableRows += `
 |${redisCol}|${ioredisCol}|${ioredisMockCol}|`;
 });
 
+const percentage = Math.floor((supportedCommands / filteredCommands.length) * 100);
+
+let color = 'red';
+if (percentage >= 25) {
+  color = 'orange';
+}
+if (percentage >= 55) {
+  color = 'yellow';
+}
+if (percentage >= 70) {
+  color = 'yellowgreen';
+}
+if (percentage >= 85) {
+  color = 'green';
+}
+if (percentage === 100) {
+  color = 'brightgreen';
+}
+
+const tableMd = `## Supported commands ![Commands Coverage: ${percentage}%](https://img.shields.io/badge/coverage-${percentage}%25-${color}.svg)
+${tableRows}`;
+
 fs.writeFile(path.resolve(__dirname, '..', 'compat.md'), tableMd, (err) => {
   if (err) throw err;
 });

src/commands/getrange.js

@@ -0,0 +1,9 @@
+export function getrange(key, start, end) {
+  const val = this.data.get(key);
+
+  if (end === -1) {
+    return val.slice(start);
+  }
+
+  return val.slice(start, end + 1);
+}

src/commands/index.js

@@ -9,6 +9,7 @@ export * from './del';
 export * from './exists';
 export * from './expire';
 export * from './get';
+export * from './getrange';
 export * from './getset';
 export * from './hdel';
 export * from './hexists';

test/commands/getrange.js

@@ -0,0 +1,27 @@
+import expect from 'expect';
+
+import MockRedis from '../../src';
+
+describe('getrange', () => {
+  const redis = new MockRedis({
+    data: {
+      foo: 'This is a string',
+    },
+  });
+
+  it('should return "This"', () =>
+    redis.getrange('foo', 0, 3).then(result => expect(result).toBe('This'))
+  );
+
+  it('should return "ing"', () =>
+    redis.getrange('foo', -3, -1).then(result => expect(result).toBe('ing'))
+  );
+
+  it('should return "This is a string"', () =>
+    redis.getrange('foo', 0, -1).then(result => expect(result).toBe('This is a string'))
+  );
+
+  it('should return "string"', () =>
+    redis.getrange('foo', 10, 100).then(result => expect(result).toBe('string'))
+  );
+});