Zed XML

XML syntax highlighting for Zed.

See the official Zed XML Language Documentation.

Adding file types

This extension only claims .xml by default, plus any file whose first line matches an XML declaration (^<.*xml). There are too many XML based formats to hardcode them all, so extra extensions are left to you.

To associate more file types, add them to your Zed settings.json:

{
  "file_types": {
    "XML": ["*.svg", "*.xsl", "*.dtd"]
  }
}

Tree-Sitter

• https://github.com/tree-sitter-grammars/tree-sitter-xml

Language Server

This extension uses the eclipse-lemminx/lemminx language server for completion, validation and hover from XSD and DTD, XML catalogs and file associations.

The lemminx binary is found in this order:

1. lsp.lemminx.binary.path in your settings;
2. a lemminx binary in your PATH;
3. otherwise the extension downloads the native binary Red Hat publishes with redhat-developer/vscode-xml/releases, for macOS (x86_64 and aarch64), Linux (x86_64 and aarch64) and Windows (x86_64, which also runs on Windows on ARM). No Java is needed. The release is pinned in src/lemminx_release.rs and the binary is checked against the SHA-256 published with it.

If the download or the checksum fails, or there is no binary for your platform, install LemMinX yourself and point the extension at it:

  "lsp": {
    "lemminx": {
      "binary": {
        "path": "/path/to/lemminx",
        "arguments": []
      }
    }
  }

Settings

Everything under lsp.lemminx.settings reaches LemMinX as its settings, both at start-up and on every workspace/configuration request. See the vscode-xml settings and the LemMinX configuration for the full list.

Relative paths in xml.catalogs and xml.fileAssociations[].systemId are resolved against the project root, as the VS Code client does, so they can live in a project's .zed/settings.json. Absolute paths and URIs (https://…, file:///…) are passed through untouched.

  "lsp": {
    "lemminx": {
      "settings": {
        "xml": {
          "catalogs": ["schemas/catalog.xml"],
          "fileAssociations": [
            { "pattern": "**/config/*.xml", "systemId": "schemas/config.xsd" }
          ],
          "format": { "maxLineWidth": 120 }
        }
      }
    }
  }

A catalog maps namespaces to schemas, which is enough for completion and hover. LemMinX only validates a document bound to a grammar: by xsi:schemaLocation, a DOCTYPE or a file association.

Updating LemMinX

To move to a new release of redhat-developer/vscode-xml, run script/update-lemminx.sh <tag> (for example script/update-lemminx.sh 0.29.3). It rewrites src/lemminx_release.rs with the tag and the SHA-256 of each binary.

Formatter

Prettier

Use prettier with prettier/plugin-xml to format:

  "languages": {
    "XML": {
      "prettier": {
        "allowed": true,
        "plugins": ["@prettier/plugin-xml"]
      },
      "formatter": "prettier",
    }
  }

Language Server

Use lemminx language server to format documents:

  "languages": {
    "XML": {
      "format_on_save": "on",
      "formatter": "language_server"
    }
  }

Zed passes its indentation settings to LemMinX when formatting (tabSize, insertSpaces). Set them in an .editorconfig:

root = true

[*.xml]
indent_style = space
indent_size = 2

or with tab_size and hard_tabs in your Zed settings:

  "languages": {
    "XML": {
      "tab_size": 2,
      "hard_tabs": false
    }
  }

Manual formatting

If you prefer, you can manually use editor::FormatDocument (ctrl-shift-i on Linux, cmd-shift-i on macOS) and disable automatic "Format on Save" with:

  "languages": {
    "XML": {
      "format_on_save": "off"
    }
  }