gatsby-remark-prismjs

// In your gatsby-config.js
plugins: [
  {
    resolve: `gatsby-transformer-remark`,
    options: {
      plugins: [
        {
          resolve: `gatsby-remark-prismjs`,
          options: {
            // Class prefix for <pre> tags containing syntax highlighting;
            // defaults to 'language-' (e.g. <pre class="language-js">).
            // If your site loads Prism into the browser at runtime,
            // (e.g. for use with libraries like react-live),
            // you may use this to prevent Prism from re-processing syntax.
            // This is an uncommon use-case though;
            // If you're unsure, it's best to use the default value.
            classPrefix: "language-",
            // This is used to allow setting a language for inline code
            // (i.e. single backticks) by creating a separator.
            // This separator is a string and will do no white-space
            // stripping.
            // A suggested value for English speakers is the non-ascii
            // character '›'.
            inlineCodeMarker: null,
            // This lets you set up language aliases.  For example,
            // setting this to '{ sh: "bash" }' will let you use
            // the language "sh" which will highlight using the
            // bash highlighter.
            aliases: {},
            // This toggles the display of line numbers globally alongside the code.
            // To use it, add the following line in gatsby-browser.js
            // right after importing the prism color scheme:
            //  require("prismjs/plugins/line-numbers/prism-line-numbers.css")
            // Defaults to false.
            // If you wish to only show line numbers on certain code blocks,
            // leave false and use the {numberLines: true} syntax below
            showLineNumbers: false,
            // If setting this to true, the parser won't handle and highlight inline
            // code used in markdown i.e. single backtick code like `this`.
            noInlineHighlight: false,
            // This adds a new language definition to Prism or extend an already
            // existing language definition. More details on this option can be
            // found under the header "Add new language definition or extend an
            // existing language" below.
            languageExtensions: [
              {
                language: "superscript",
                extend: "javascript",
                definition: {
                  superscript_types: /(SuperType)/,
                },
                insertBefore: {
                  function: {
                    superscript_keywords: /(superif|superelse)/,
                  },
                },
              },
            ],
            // Customize the prompt used in shell output
            // Values below are default
            prompt: {
              user: "root",
              host: "localhost",
              global: false,
            },
            // By default the HTML entities <>&'" are escaped.
            // Add additional HTML escapes by providing a mapping
            // of HTML entities and their escape value IE: { '}': '&#123;' }
            escapeEntities: {},
          },
        },
      ],
    },
  },
]

// gatsby-browser.js
require("prismjs/themes/prism-solarizedlight.css")

.gatsby-highlight-code-line {
  background-color: #feb;
  display: block;
  margin-right: -1em;
  margin-left: -1em;
  padding-right: 1em;
  padding-left: 0.75em;
  border-left: 0.25em solid #f99;
}

/**
 * Add back the container background-color, border-radius, padding, margin
 * and overflow that we removed from <pre>.
 */
.gatsby-highlight {
  background-color: #fdf6e3;
  border-radius: 0.3em;
  margin: 0.5em 0;
  padding: 1em;
  overflow: auto;
}

/**
 * Remove the default PrismJS theme background-color, border-radius, margin,
 * padding and overflow.
 * 1. Make the element just wide enough to fit its content.
 * 2. Always fill the visible space in .gatsby-highlight.
 * 3. Adjust the position of the line numbers
 */
.gatsby-highlight pre[class*="language-"] {
  background-color: transparent;
  margin: 0;
  padding: 0;
  overflow: initial;
  float: left; /* 1 */
  min-width: 100%; /* 2 */
}

// gatsby-browser.js
require("prismjs/plugins/line-numbers/prism-line-numbers.css")

/**
 * If you already use line highlighting
 */

/* Adjust the position of the line numbers */
.gatsby-highlight pre[class*="language-"].line-numbers {
  padding-left: 2.8em;
}

/**
 * If you only want to use line numbering
 */

.gatsby-highlight {
  background-color: #fdf6e3;
  border-radius: 0.3em;
  margin: 0.5em 0;
  padding: 1em;
  overflow: auto;
}

.gatsby-highlight pre[class*="language-"].line-numbers {
  padding: 0;
  padding-left: 2.8em;
  overflow: initial;
}

// gatsby-browser.js
require("prismjs/plugins/command-line/prism-command-line.css")

.command-line-prompt > span:before {
  color: #999;
  content: " ";
  display: block;
  padding-right: 0.8em;
}

/* Prompt for all users */
.command-line-prompt > span[data-user]:before {
  content: "[" attr(data-user) "@" attr(data-host) "] $";
}

/* Prompt for root */
.command-line-prompt > span[data-user="root"]:before {
  content: "[" attr(data-user) "@" attr(data-host) "] #";
}

.command-line-prompt > span[data-prompt]:before {
  content: attr(data-prompt);
}

```javascript
// In your gatsby-config.js
plugins: [
  {
    resolve: `gatsby-transformer-remark`,
    options: {
      plugins: [
        `gatsby-remark-prismjs`,
      ]
    }
  }
]
```

```javascript{numberLines: true}
// In your gatsby-config.js
plugins: [
  {
    resolve: `gatsby-transformer-remark`,
    options: {
      plugins: [
        `gatsby-remark-prismjs`,
      ]
    }
  }
]
```

```javascript{numberLines: 5}
// In your gatsby-config.js
plugins: [
  {
    resolve: `gatsby-transformer-remark`,
    options: {
      plugins: [
        `gatsby-remark-prismjs`,
      ]
    }
  }
]
```

```jsx
class FlavorForm extends React.Component {  constructor(props) {
    super(props);
    this.state = {value: 'coconut'};

    this.handleChange = this.handleChange.bind(this);
    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleChange(event) {
    this.setState({value: event.target.value});  }

  handleSubmit(event) {    alert('Your favorite flavor is: ' + this.state.value);    event.preventDefault();  }
  render() {
    return (
      <form onSubmit={this.handleSubmit}>        <label>
          Pick your favorite flavor:
          <select value={this.state.value} onChange={this.handleChange}>            <option value="grapefruit">Grapefruit</option>            <option value="lime">Lime</option>            <option value="coconut">Coconut</option>            <option value="mango">Mango</option>          </select>        </label>
        <input type="submit" value="Submit" />
      </form>    );
  }
}
```

```javascript{1,4-6}
// In your gatsby-config.js
plugins: [
  {
    resolve: `gatsby-transformer-remark`,
    options: {
      plugins: [
        `gatsby-remark-prismjs`,
      ]
    }
  }
]
```

```shell{outputLines: 2-10,12}

```shell{promptUser: alice}{promptHost: dev.localhost}

```diff-javascript

I can highlight `css±.some-class { background-color: red }` with CSS syntax.

languageExtensions: [
  {
    language: "superscript",
    extend: "javascript",
    definition: {
      superscript_types: /(SuperType)/,
    },
    insertBefore: {
      function: {
        superscript_keywords: /(superif|superelse)/,
      },
    },
  },
]

<span class="token superscript_keywords">superif</span>