feat(tag): add unless tag

unless tag is opposite of if tag

src/Tags/UnlessTag.js

@@ -0,0 +1,104 @@
+'use strict'
+
+/*
+ * edge
+ *
+ * (c) Harminder Virk <virk@adonisjs.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+*/
+
+const BaseTag = require('./BaseTag')
+
+/**
+ * The official unless tag. It is used
+ * as `@unless` inside templates.
+ *
+ * @class UnlessTag
+ * @extends {BaseTag}
+ * @static
+ */
+class UnlessTag extends BaseTag {
+  /**
+   * The tag name to used for registering the tag
+   *
+   * @attribute tagName
+   *
+   * @return {String}
+   */
+  get tagName () {
+    return 'unless'
+  }
+
+  /**
+   * Whether tag is a block level tag or
+   * not.
+   *
+   * @attribute isBlock
+   *
+   * @return {Boolean}
+   */
+  get isBlock () {
+    return true
+  }
+
+  /**
+   * The expressions allowed to be passed to the
+   * tag. Any other expressions will cause an
+   * error.
+   *
+   * @attribute allowedExpressions
+   *
+   * @return {Array}
+   */
+  get allowedExpressions () {
+    return ['BinaryExpression', 'Literal', 'Identifier', 'CallExpression', 'MemberExpression', 'UnaryExpression']
+  }
+
+  /**
+   * Compile the template and write to the buffer.
+   *
+   * @method compile
+   *
+   * @param  {Object} compiler
+   * @param  {Object} lexer
+   * @param  {Object} buffer
+   * @param  {String} options.body
+   * @param  {Array} options.childs
+   * @param  {Number} options.lineno
+   *
+   * @return {void}
+   */
+  compile (compiler, lexer, buffer, { body, childs, lineno }) {
+    const compiledStatement = this._compileStatement(lexer, body, lineno).toStatement()
+
+    /**
+     * Open if opposite of tag
+     */
+    buffer.writeLine(`if (!(${compiledStatement})) {`)
+    buffer.indent()
+
+    /**
+     * Re-parse all childs via compiler.
+     */
+    childs.forEach((child) => compiler.parseLine(child))
+
+    /**
+     * Close the opposite if tag
+     */
+    buffer.dedent()
+    buffer.writeLine('}')
+  }
+
+  /**
+   * Nothing needs to be in done in runtime for
+   * an if tag.
+   *
+   * @method run
+   */
+  run () {
+  }
+}
+
+module.exports = UnlessTag

src/Tags/index.js

@@ -20,5 +20,6 @@ module.exports = {
   sectionTag: new (require('./SectionTag'))(),
   yieldTag: new (require('./YieldTag'))(),
   debugger: new (require('./DebuggerTag'))(),
-  raw: new (require('./RawTag'))()
+  raw: new (require('./RawTag'))(),
+  unless: new (require('./UnlessTag'))()
 }

test/unit/tags/if.spec.js

@@ -121,7 +121,7 @@ test.group('Tags | If ', (group) => {
     }).bind(this)()`)
   })
 
-  test('parse block with arithmatic expression', (assert) => {
+  test('parse block with arithmetic expression', (assert) => {
     const statement = dedent`
     @if(2 + 2)
       <p> It is {{ 2 + 2 }} </p>
@@ -139,7 +139,7 @@ test.group('Tags | If ', (group) => {
     }).bind(this)()`)
   })
 
-  test('parse block with arithmatic and binary expression expression', (assert) => {
+  test('parse block with arithmetic and binary expression expression', (assert) => {
     const statement = dedent`
     @if(2 + 2 === cartTotal)
       <p> Hello {{ cartTotal }} </p>

test/unit/tags/unless.spec.js

@@ -0,0 +1,228 @@
+'use strict'
+
+/*
+ * adonis-edge
+ *
+ * (c) Harminder Virk <virk@adonisjs.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+*/
+
+const test = require('japa')
+const Template = require('../../../src/Template')
+const dedent = require('dedent-js')
+
+test.group('Tags | Unless ', (group) => {
+  group.before(() => {
+    require('../../../test-helpers/transform-tags')(this, require('../../../src/Tags'))
+  })
+
+  test('parse simple unless block to compiled template', (assert) => {
+    const statement = dedent`
+      @unless(username === 'virk')
+        <p> Hello virk </p>
+      @endunless
+    `
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(this.context.resolve('username') === 'virk')) {
+        out += \`  <p> Hello virk </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('parse block with else', (assert) => {
+    const statement = dedent`
+    @unless(username === 'virk')
+      <p> Hello virk </p>
+    @else
+      <p> Hello anonymous </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(this.context.resolve('username') === 'virk')) {
+        out += \`  <p> Hello virk </p>\\n\`
+      } else {
+        out += \`  <p> Hello anonymous </p>\\n\`
+      }
+      return out
+    }).bind(this)()
+    `)
+  })
+
+  test('parse block with literal inside unless', (assert) => {
+    const statement = dedent`
+    @unless('virk')
+      <p> Hello virk </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!('virk')) {
+        out += \`  <p> Hello virk </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('parse block with identifier inside unless', (assert) => {
+    const statement = dedent`
+    @unless(username)
+      <p> Hello {{ username }} </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(this.context.resolve('username'))) {
+        out += \`  <p> Hello \${this.context.escape(this.context.resolve('username'))} </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('parse block with arithmetic expression', (assert) => {
+    const statement = dedent`
+    @unless(2 + 2)
+      <p> It is {{ 2 + 2 }} </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(2 + 2)) {
+        out += \`  <p> It is \${this.context.escape(2 + 2)} </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('parse block with arithmatic and binary expression expression', (assert) => {
+    const statement = dedent`
+    @unless(2 + 2 === cartTotal)
+      <p> Hello {{ cartTotal }} </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(2 + 2 === this.context.resolve('cartTotal'))) {
+        out += \`  <p> Hello \${this.context.escape(this.context.resolve('cartTotal'))} </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('parse when a function has been passed', (assert) => {
+    const statement = dedent`
+    @unless(count(users))
+      <p> There are {{ count(users) }} </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(this.context.callFn('count', [this.context.resolve('users')]))) {
+        out += \`  <p> There are \${this.context.escape(this.context.callFn('count', [this.context.resolve('users')]))} </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('parse when a native function is called', (assert) => {
+    const statement = dedent`
+    @unless(users.indexOf('virk') > -1)
+      <p> Hello {{ users['virk'] }} </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(this.context.resolve('users').indexOf('virk') > -1)) {
+        out += \`  <p> Hello \${this.context.escape(this.context.accessChild(this.context.resolve('users'), ['virk']))} </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('parse when a property accessor is passed', (assert) => {
+    const statement = dedent`
+    @unless(user.isLoggedIn)
+      <p> Hello {{ user.username }} </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(this.context.accessChild(this.context.resolve('user'), ['isLoggedIn']))) {
+        out += \`  <p> Hello \${this.context.escape(this.context.accessChild(this.context.resolve('user'), ['username']))} </p>\\n\`
+      }
+      return out
+    }).bind(this)()`)
+  })
+
+  test('throw exception when assignment expression is passed', (assert) => {
+    const statement = dedent`
+    @unless(age = 22)
+      <p> You are 22 years old </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = () => template.compileString(statement)
+    assert.throw(output, 'lineno:1 charno:0 E_INVALID_EXPRESSION: Invalid expression <age = 22> passed to (unless) block')
+  })
+
+  test('throw exception when sequence expression is passed', (assert) => {
+    const statement = dedent`
+    @unless(age, username)
+      <p> You are 22 years old </p>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = () => template.compileString(statement)
+    assert.throw(output, 'lineno:1 charno:0 E_INVALID_EXPRESSION: Invalid expression <age, username> passed to (unless) block')
+  })
+
+  test('should work with unary expression', (assert) => {
+    const statement = dedent`
+    @unless(!age)
+      <h2> Please type your age </h2>
+    @endunless`
+
+    const template = new Template(this.tags)
+    const output = template.compileString(statement)
+    assert.equal(output, dedent`
+    return (function templateFn () {
+      let out = new String()
+      if (!(!this.context.resolve('age'))) {
+        out += \`  <h2> Please type your age </h2>\\n\`
+      }
+      return out
+    }).bind(this)()
+    `)
+  })
+})