From ef1374097f781975dc5634217301d972eaa8cce3 Mon Sep 17 00:00:00 2001
From: Patrick Steele-Idem <pnidem@gmail.com>
Date: Tue, 16 Feb 2016 22:24:03 -0700
Subject: [PATCH] Marko v3: Allow <else if(foo)>

---
 taglibs/core/else-tag.js                      | 25 +++++++++++++++++--
 .../autotest/if-else-if-concise/expected.html |  1 +
 .../if-else-if-concise/template.marko         |  4 +++
 .../autotest/if-else-if-concise/test.js       |  1 +
 4 files changed, 29 insertions(+), 2 deletions(-)
 create mode 100644 test/fixtures/render/autotest/if-else-if-concise/expected.html
 create mode 100644 test/fixtures/render/autotest/if-else-if-concise/template.marko
 create mode 100644 test/fixtures/render/autotest/if-else-if-concise/test.js

diff --git a/taglibs/core/else-tag.js b/taglibs/core/else-tag.js
index 19c8989e4..425285081 100644
--- a/taglibs/core/else-tag.js
+++ b/taglibs/core/else-tag.js
@@ -1,5 +1,7 @@
+'use strict';
+
 module.exports = function nodeFactory(el, context) {
-    var attributes = el.attributes;
+
     var elseStatement = context.builder.elseStatement();
 
     var argument = el.argument;
@@ -7,8 +9,27 @@ module.exports = function nodeFactory(el, context) {
         context.addError(elseStatement, 'Invalid <else> tag. Argument is not allowed');
     }
 
-    if (attributes.length) {
+    if (el.hasAttribute('if')) {
+        let ifAttr = el.getAttribute('if');
+        el.removeAttribute('if');
+
+        if (el.attributes.length) {
+            context.addError(elseStatement, 'Invalid <else if> tag. Only the "if" attribute is allowed.');
+            return el;
+        }
+
+        var testExpression = ifAttr.argument;
+        if (!testExpression) {
+            context.addError(elseStatement, 'Invalid <else if> tag. Invalid "if" attribute. Expected: <else if(<test>)>');
+            return el;
+        }
+        var elseIfStatement = context.builder.elseIfStatement(testExpression);
+        return elseIfStatement;
+    }
+
+    if (el.attributes.length) {
         context.addError(elseStatement, 'Invalid <else> tag. Attributes not allowed.');
+        return el;
     }
 
     return elseStatement;
diff --git a/test/fixtures/render/autotest/if-else-if-concise/expected.html b/test/fixtures/render/autotest/if-else-if-concise/expected.html
new file mode 100644
index 000000000..7371f47a6
--- /dev/null
+++ b/test/fixtures/render/autotest/if-else-if-concise/expected.html
@@ -0,0 +1 @@
+B
\ No newline at end of file
diff --git a/test/fixtures/render/autotest/if-else-if-concise/template.marko b/test/fixtures/render/autotest/if-else-if-concise/template.marko
new file mode 100644
index 000000000..7406859d7
--- /dev/null
+++ b/test/fixtures/render/autotest/if-else-if-concise/template.marko
@@ -0,0 +1,4 @@
+if(false)
+    - A
+else if(true)
+    - B
\ No newline at end of file
diff --git a/test/fixtures/render/autotest/if-else-if-concise/test.js b/test/fixtures/render/autotest/if-else-if-concise/test.js
new file mode 100644
index 000000000..c4013b344
--- /dev/null
+++ b/test/fixtures/render/autotest/if-else-if-concise/test.js
@@ -0,0 +1 @@
+exports.templateData = {};