From 4bab62eda4dde060172fada517dd85fa6233f7e4 Mon Sep 17 00:00:00 2001
From: Avi Goldman <avrahamymgoldman@gmail.com>
Date: Mon, 16 Oct 2017 00:16:45 -0700
Subject: [PATCH] moved logic for shorthands into render function

---
 packages/heml-render/src/index.js         | 14 +------
 packages/heml-render/src/renderElement.js | 46 ++++++++++++-----------
 2 files changed, 26 insertions(+), 34 deletions(-)

diff --git a/packages/heml-render/src/index.js b/packages/heml-render/src/index.js
index c4b977f..1e6c789 100644
--- a/packages/heml-render/src/index.js
+++ b/packages/heml-render/src/index.js
@@ -72,18 +72,6 @@ async function renderElements (elements, globals) {
 
     const renderedValue = await Promise.resolve(renderElement(element, attrs, contents))
 
-    switch (renderedValue) {
-      case false:
-        $node.remove()
-        break
-
-      case true:
-        // do nothing
-        break
-
-      default:
-        $node.replaceWith(renderedValue.trim())
-        break
-    }
+    $node.replaceWith(renderedValue.trim())
   }
 }
diff --git a/packages/heml-render/src/renderElement.js b/packages/heml-render/src/renderElement.js
index e99b913..e9259e2 100644
--- a/packages/heml-render/src/renderElement.js
+++ b/packages/heml-render/src/renderElement.js
@@ -1,10 +1,15 @@
 import stringifyAttributes from 'stringify-attributes'
 import isPromise from 'is-promise'
-import { isString, isArray, defaults, mapValues, castArray } from 'lodash'
+import { isPlainObject, defaults, mapValues, castArray, compact } from 'lodash'
 import selfClosingHtmlTags from 'html-tags/void'
 
 export default function (name, attrs, contents) {
-  if (!isString(name)) {
+  if (!name || (isPlainObject(name) && !name.render)) {
+    throw new Error(`name must be a HEML element or HTML tag name (.e.g 'td'). Received: ${JSON.stringify(name)}`)
+  }
+
+  if (isPlainObject(name) && name.render) {
+    /** set the defaults and massage attribute values */
     attrs = defaults({}, attrs, name.defaultAttrs || {})
     attrs = mapValues(attrs, (value, name) => {
       if ((value === '' && name !== 'class') || value === 'true' || value === 'on') { return true }
@@ -14,29 +19,28 @@ export default function (name, attrs, contents) {
       return value
     })
 
-    /** custom elements can return promises, arrays, strings */
+    /**
+     * custom elements can return promises, arrays, or strings
+     *
+     * we will:
+     * 1. check for the shorthands and render on that
+     * 2. return a string synchronously if we can
+     * 3. return a string in a promise
+     */
     const renderResults = castArray(name.render(attrs, contents))
 
-    /** we want to return synchronously if we can */
-    if (!isPromise(renderResults) && renderResults.filter(isPromise).length === 0) { return renderResults.join('') }
+    /** 1. catch shorthands for rerendering the element */
+    if (renderResults.length === 1 && renderResults[0] === true) {
+      return renderResults(name.tagName, attrs, contents)
+    }
+
+    /** 2. we want to return synchronously if we can */
+    if (renderResults.filter(isPromise).length === 0) {
+      return compact(renderResults).join('')
+    }
 
     /** otherwise, combine the array of promises/strings into a single string */
-    return Promise.resolve(name.render(attrs, contents))
-      .then((results) => {
-        if (isArray(results)) {
-          return Promise.all(results).then((results) => {
-            let str = ''
-
-            results.forEach(function (part) {
-              str += part
-            })
-
-            return str
-          })
-        }
-
-        return results
-      })
+    return Promise.all(renderResults).then((results) => compact(results).join(''))
   }
 
   /** if we have a regular ol element go ahead and convert it to a string */