Initial commit

.gitignore

+# Dependency directories
+node_modules/
+
+# Logs
+logs/
+*.log
+npm-debug.log*
+
+# Optional npm cache directory
+.npm/
+
+# Optional REPL history
+.node_repl_history/

.npmignore

+*

LICENCE

+MIT License
+
+Copyright (c) 2018 Vadym Gidulian
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

+# is-vue-functional-component-prop-truthy
+Checks if a property passed to Vue functional component is truthy
+
+## Usage
+
+```js
+const isTruthy = require(...)(options);
+
+... = isTruthy(context, propName);
+```
+
+- `options`
+    - `isPropsOmitted`
+
+        > Note: in versions before 2.3.0, the `props` option is required if you wish to accept props in a functional component. In 2.3.0+ you can omit the `props` option and all attributes found on the component node will be implicitly extracted as props.
+        >
+        > — [Vue.js Guide](https://vuejs.org/v2/guide/render-function.html#Functional-Components)
+
+- `context` – the component's context
+- `propName` – the property name
+
+### Examples
+
+```js
+const isTruthy = require(...)();
+
+module.exports = {
+	functional: true,
+	props: ['prop'],
+	render(h, context) {
+		const isProp = isTruthy(context, 'prop');
+		...
+	}
+};
+```
+```js
+const isTruthy = require(...)({isPropsOmitted: true});
+
+module.exports = {
+	functional: true,
+	render(h, context) {
+		const isProp = isTruthy(context, 'prop');
+		...
+	}
+};
+```
+
+## Caveats
+
+|Code                            |`isPropsOmitted`|`!isPropsOmitted`|`!isPropsOmitted`, `!props.includes('prop')`|
+|--------------------------------|----------------|-----------------|--------------------------------------------|
+|`<component/>`                  |`false`         |`false`          |`false`                                     |
+|`<component prop/>`             |`true`          |`false`²         |`true`³                                     |
+|`<component prop=""/>`          |`true`          |`false`²         |`true`³                                     |
+|`<component prop="prop"/>`      |`true`          |`true`           |`true`³                                     |
+|`<component prop="false"/>`     |`true`          |`true`           |`true`³                                     |
+|`<component :prop="false"/>`    |`false`         |`false`          |`true`³                                     |
+|`<component :prop="undefined"/>`|`false`         |`false`          |`true`³                                     |
+|`<component :prop="null"/>`     |`false`         |`false`          |`true`³                                     |
+|`<component :prop="0"/>`        |`false`         |`false`          |`true`³                                     |
+|`<component :prop="NaN"/>`      |`false`         |`false`          |`true`³                                     |
+|`<component :prop="''"/>`       |`true`¹         |`false`          |`true`³                                     |
+
+1. `:prop="''"` considered the same as `prop=""`
+
+2. `prop=""` considered the same as `:prop="''"`
+
+3. Since `prop` is not declared as prop, it will be resolved to `true` as attribute, because of its presence

index.js

+'use strict';
+
+module.exports = function (options) {
+	options = Object.assign({}, {isPropsOmitted: false}, options);
+	
+	return function (context, name) {
+		if (options.isPropsOmitted) return (name in context.props) && (typeof context.props[name] === 'string');
+		
+		if (name in context.props) {
+			return !!context.props[name];
+		}
+		
+		return context.data.attrs && (name in context.data.attrs);
+	};
+};

package.json

+{
+	"name":        "@gviagroup/is-vue-functional-component-prop-truthy",
+	"version":     "1.0.0",
+	"description": "Checks if a property passed to Vue functional component is truthy",
+	"license":     "MIT",
+	
+	"main": "index.js",
+	
+	"peerDependencies":  {
+		"vue": ">=2"
+	}
+}