moldable

A CLI tool for code generation under the influence of plop and scaffdog. It has the best of each tool, yet it is faster and more flexible. See the benchmarks for more information.

Installation

npm install -g moldable

Quick Start

Create a .moldable folder in the root directory of your application, and create Markdown file within it shown below. Name the file quick-start.md.

---
name: "quick-start"
description: "Quick Start"
prompts:
  - type: "base"
    name: "name"
    message: "Type your name"
    validate: "{{if eq (len .input) 0}}Name must have more than - characters{{end}}"
  - type: "select"
    name: "favoriteColor"
    message: "Select your favorite color"
    choices:
      - "Red"
      - "Green"
      - "Blue"
actions:
  - type: "add"
    path: "src/quick-start.json"
    template: "quick-start.json"
---

# quick-start.json

```json
{
  "name": "{{.name}}",
  "favoriteColor": "{{.favoriteColor}}"
}
```

Execute moldable in the root directory of your application, and select the quick-start generator.

# Answer the questions
? Select Generator:
  ▸ quick-start - Quick Start

✔  Type your name : John Doe█

?  Select your favorite color :
  ▸ Red
    Green
    Blue

# Results
🖨  Added:
  src/quick-start.json

Answer the questions that appear, and the code will be generated in the quick-start.json file.

{
  "name": "John Doe",
  "favoriteColor": "Red"
}

Advanced Usage

You can describe a generator for generating any code. Create a /.moldable folder in the root directory of your application, and create Markdown files within it.

.
└──  .moldable
    ├── foo.md
    └── bar.md

The name of the Markdown file corresponds to the generator name displayed when you launch moldable. When you run moldable, an interactive question starts according to the selected generator, and when all are answered, code is generated. This generator is divided into metadata (in YAML format) and content (in Markdown format). The structure of the metadata is as follows. You can use the syntax of Go's text/template in some properties.

Name	Description	Required	Type	Example
name	Template name (must match the Markdown file name)	✅	String	"pages"
description	Template description	✅	String	"Page Generator"
prompts	Questions to be asked sequentially after selecting a template	✅	Array of mapping	type: "base" name: "name" message: "Type a page name"
actions	Settings for generating code using the values of the answers to the questions	✅	Array of mapping	type: "add" path: "src/app/{{.name}}/page.tsx" template: "{{.name | pascal}}/page.tsx"

The structure of each element of the prompts value is as follows.

Name	Description	Required	Type
type	Format of the question ・base: Text input ・select: Single selection ・multiselect: Multiple selection ・confirm: Y/N binary choice	✅	"base" | "select" | "multiselect" | "confirm"
name	Variable name to store the result of the question. In places where text/template is valid, it can be referenced with a . start.	✅	String
message	Content of the question	✅	String
prefix	Supplement to the question, displayed before the question		String
suffix	Supplement to the question, displayed after the question		String
when	Place to skip the question. The results of the questions up to the current question can be referenced.		String(text/template)
validate	Place to validate the question. The value of the question being entered can be referenced with .input.		String(text/template)
defaultValues	Default value of the result of the question Data type ・base: String ・select: String ・multiselect: Array of String ・confirm: Boolean		Any
choises	Choices for select and multiselect	Required if type is select or multiselect	Array of String

The structure of each element of the actions value is as follows.

Name	Description	Required	Type
type	Type of code generation	✅	"add" | "append"
path	Destination of the code output	✅	String(text/template)
template	Template name for code generation (must match the heading in the content)	✅	String(text/template)
skip	Place to skip code generation		String(text/template)
pattern	Destination to add code in append	Required if type is append	String

In addition, for variables referenced within text/template, you can convert to the following cases using the format .var | case.

Name	Case
camel	camelCase
snake	snake_case
kebab	kebab-case
dash	dash-case
dot	dot.case
proper	ProperCase
pascal	PascalCase
lower	lower case
sentence	Sentence case
constant	CONSTANT_CASE
title	Title Case

[!NOTE]

By attaching OnlyAlphanumeric to the end of each case modifier (e.g. pascalOnlyAlphanumeric), if the first character of the string is not alphanumeric, it is excluded and the case is converted. For example, [projectId] is converted to ProjectId with pascalOnlyAlphanumeric.

The content consists of headings and code blocks as follows.

---
actions:
  - type: "add"
    template: "page.tsx"
---

# page.tsx

```tsx
export const Page = (children: { children: React.ReactNode }) => <div>{children}</div>;
```

As mentioned earlier, the template of any element contained in actions needs to match the heading in the content. The syntax of text/template can also be used for headings.

Benchmarks

Environment

• OS: macOS Monterey 12.6.3
• CPU: Apple M1 Max
• Memory: 64GB
• Node.js: 20.11.1
• npm: 10.5.1

We measured the time it took to generate a simple React component with each package. The benchmark project is available here.

import React from "react";

export const {{ name }}: React.FC = (children: { children: React.ReactNode }) => <div>{children}</div>;

Result

Package	Version	Average time of 10 times(ms)
plop	6.2.11	0.233
scaffdog	3.0.0	0.385
moldable	0.0.4	0.182

Moldable is the fastest. This is because it is written in Go and executed by node after compiling it into a binary.

Third Party License

Parts of the code from the following projects have been borrowed and modified for use.

• Plop.js(MIT License)
• Scaffdog(MIT License)
• eslint-interactive(MIT License)

The list of licenses is available at THIRD_PARTY_LICENSE.

License

MIT License

Developers

• Shuta Hirai - GitHub
• Satoshi Kotake - GitHub
• Takuma Shibuya - GitHub

Copyright

CyberAgent, Inc. All rights reserved.