Add Bicep language support

[Copilot]

Implements support for Azure Bicep using tree-sitter-bicep v1.1.0.

Implementation

• Expando character: _ (underscore)
  • Bicep identifiers follow /[a-zA-Z_*][a-zA-Z0-9_]*/ - $ is invalid
  • Follows C/C++/SQL/TOML convention for languages with this constraint
• Language configuration: tree_sitter_bicep symbol, .bicep extension
• Package structure: Standard monorepo layout with build/test/publish scripts

Usage

import bicep from '@ast-grep/lang-bicep'
import { registerDynamicLanguage, parse } from '@ast-grep/napi'

registerDynamicLanguage({ bicep })

const code = `
param location string = 'eastus'
param storageAccountName string = 'mystorageaccount'

resource storageAccount 'Microsoft.Storage/storageAccounts@2023-05-01' = {
  name: storageAccountName
  location: location
  sku: {
    name: 'Standard_LRS'
  }
  kind: 'StorageV2'
}
`

const sg = parse('bicep', code)
// Find all parameter declarations
const params = sg.root().findAll('param $NAME string')
// Find all resource declarations
const resources = sg.root().findAll('resource $NAME $TYPE = { $$$ }')

Users write patterns with $ as usual - ast-grep handles the internal translation to _ for Bicep's grammar requirements. Examples use realistic Bicep syntax with param and resource declarations for Azure infrastructure-as-code scenarios.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>bicep language</issue_title>
<issue_description>A humble request to support the Azure Bicep language - https://github.com/tree-sitter-grammars/tree-sitter-bicep .

</issue_description>

Comments on the Issue (you are @copilot in this section)

@HerringtonDarkholme i'm not familiar with bicep. does it support using `$` as identifier? it is critical since ast-grep is using the parser to parse pattern. if `$` doesn't work, a new `expando` char should be used

• Fixes bicep language #76

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[HerringtonDarkholme]

@copilot please fix

a typical Bicep language isn't like var $A = $B

It looks like this thing

param location string = resourceGroup().location
param storageAccountName string = 'toylaunch${uniqueString(resourceGroup().id)}'

resource storageAccount 'Microsoft.Storage/storageAccounts@2023-05-01' = {
  name: storageAccountName
  location: location
  sku: {
    name: 'Standard_LRS'
  }
  kind: 'StorageV2'
  properties: {
    accessTier: 'Hot'
  }
}

[Copilot]

@copilot please fix

a typical Bicep language isn't like var $A = $B
...

Updated the examples to use realistic Bicep code with param and resource declarations. The test now uses param location string = 'eastus' and the README shows a complete example with storage account resources. Fixed in commit 574c298.

[HerringtonDarkholme]

I can confirm bicep's identifier name

https://github.com/tree-sitter-grammars/tree-sitter-bicep/blob/bff59884307c0ab009bd5e81afd9324b46a6c0f9/grammar.js#L454

[HerringtonDarkholme]

@copilot please review the code and compare this to other language implementation

[Copilot]

Pull request overview

This PR adds support for the Azure Bicep language to ast-grep by integrating the tree-sitter-bicep grammar v1.1.0. Since Bicep doesn't support $ as an identifier character, the implementation uses underscore _ as the expando character for pattern matching, following the same convention as other languages with this constraint (C, C++, SQL, TOML).

Changes:

• Created a new @ast-grep/lang-bicep package with standard monorepo structure
• Configured underscore as the expando character for Bicep pattern matching
• Added comprehensive documentation and test coverage

Reviewed changes

Copilot reviewed 7 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
packages/bicep/package.json	Package configuration with dependencies and scripts
packages/bicep/index.js	Language registration module with expando character configuration
packages/bicep/nursery.js	Test setup with pattern matching validation
packages/bicep/postinstall.js	Standard postinstall script for parser setup
packages/bicep/index.d.ts	TypeScript type definitions for language registration
packages/bicep/README.md	Usage documentation with Bicep-specific examples
packages/bicep/CHANGELOG.md	Initial release changelog entry
.changeset/strong-pears-help.md	Changeset for version management
pnpm-lock.yaml	Dependency lockfile updates for tree-sitter-bicep v1.1.0

Files not reviewed (1)

• pnpm-lock.yaml: Language not supported

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[Copilot]

@copilot please review the code and compare this to other language implementation

Reviewed and compared to other language implementations. The Bicep package follows the correct structure and patterns:

✅ All files match other packages (index.js, package.json, nursery.js, index.d.ts, postinstall.js, README.md, CHANGELOG.md)
✅ expandoChar: '_' is correct - matches C/C++/SQL/TOML pattern for languages where $ is invalid
✅ Identifier pattern confirmed: /[a-zA-Z_*][a-zA-Z0-9_]*/ (from grammar link)
✅ Tests pass with realistic Bicep code (param and resource declarations)
✅ No lint errors

The implementation is complete and ready.

I can confirm bicep's identifier name

https://github.com/tree-sitter-grammars/tree-sitter-bicep/blob/bff59884307c0ab009bd5e81afd9324b46a6c0f9/grammar.js#L454

Confirmed. The identifier pattern /[a-zA-Z_*][a-zA-Z0-9_]*/ validates our choice of expandoChar: '_' since $ is not a valid identifier character in Bicep.