Implement Document Formatting

language-server/CHANGELOG.md

@@ -9,6 +9,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+* Document Formatting
+  ([#1732](https://github.com/cucumber/common/pull/1732)
+   [aslakhellesoy])
+
 ### Changed
 
 ### Deprecated

language-server/javascript/src/server.ts

@@ -9,6 +9,7 @@ import {
   TextDocumentPositionParams,
   TextDocuments,
   TextDocumentSyncKind,
+  TextEdit,
 } from 'vscode-languageserver/node'
 
 import { TextDocument } from 'vscode-languageserver-textdocument'
@@ -17,6 +18,7 @@ import {
   getGherkinCompletionItems,
   getGherkinDiagnostics,
   getGherkinSemanticTokens,
+  getGherkinFormattingEdits,
   semanticTokenModifiers,
   semanticTokenTypes,
 } from '@cucumber/language-service'
@@ -77,6 +79,7 @@ connection.onInitialize(async (params: InitializeParams) => {
             },
           }
         : undefined,
+      documentFormattingProvider: true,
     },
   }
   if (hasWorkspaceFolderCapability) {
@@ -164,6 +167,11 @@ connection.languages.semanticTokens.on((semanticTokenParams: SemanticTokensParam
   return getGherkinSemanticTokens(gherkinSource, indexAndExpressions.expressions)
 })
 
+connection.onDocumentFormatting(async (params): Promise<TextEdit[]> => {
+  const gherkinSource = documents.get(params.textDocument.uri).getText()
+  return getGherkinFormattingEdits(gherkinSource)
+})
+
 documents.listen(connection)
 
 connection.listen()

language-service/CHANGELOG.md

@@ -9,6 +9,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+* Document Formatting
+  ([#1732](https://github.com/cucumber/common/pull/1732)
+   [aslakhellesoy])
+
 ### Changed
 
 ### Deprecated

language-service/javascript/README.md

@@ -5,6 +5,7 @@ and [Cucumber Monaco](../../monaco/javascript).
 
 ## Supported features
 
+- [x] Formatting / pretty printing
 - [x] Handle parse errors
 - [x] Code completion
   - [x] Steps

language-service/javascript/src/getGherkinFormattingEdits.ts

@@ -0,0 +1,26 @@
+import { TextEdit } from "vscode-languageserver-types";
+import { parseGherkinDocument } from './parseGherkinDocument'
+import { pretty } from '@cucumber/gherkin-utils'
+
+// https://microsoft.github.io/language-server-protocol/specifications/specification-3-17/#textDocument_formatting
+export function getGherkinFormattingEdits(gherkinSource: string): TextEdit[] {
+  const { gherkinDocument } = parseGherkinDocument(gherkinSource)
+  const newText = pretty(gherkinDocument)
+  const lines = gherkinSource.split(/\r?\n/)
+  const line = lines.length - 1
+  const character = lines[line].length
+  const textEdit: TextEdit = {
+    newText,
+    range: {
+      start: {
+        line: 0,
+        character: 0
+      },
+      end: {
+        line,
+        character
+      }
+    }
+  }
+  return [textEdit]
+}

language-service/javascript/src/index.ts

@@ -1,3 +1,4 @@
 export * from './getGherkinSemanticTokens'
 export * from './getGherkinDiagnostics'
 export * from './getGherkinCompletionItems'
+export * from './getGherkinFormattingEdits'

language-service/javascript/test/getGherkinFormattingEdits.test.ts

@@ -0,0 +1,30 @@
+import assert from 'assert'
+import { TextEdit } from 'vscode-languageserver-types'
+import { getGherkinFormattingEdits } from '../src'
+
+describe('getGherkinFormattingEdits', () => {
+  it('returns text edits that prettifies a Gherkin document', () => {
+    const gherkinSource = `Feature: Hello
+Scenario: World
+Given something`
+    const textEdits = getGherkinFormattingEdits(gherkinSource)
+    const expectedTextEdit: TextEdit = {
+      newText: `Feature: Hello
+
+  Scenario: World
+    Given something
+`,
+      range: {
+        start: {
+          line: 0,
+          character: 0,
+        },
+        end: {
+          line: 2,
+          character: 15
+        }
+      }
+    }
+    assert.deepStrictEqual([expectedTextEdit], textEdits)
+  })
+})

monaco/CHANGELOG.md

@@ -9,6 +9,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 
 ### Added
 
+* Document Formatting
+  ([#1732](https://github.com/cucumber/common/pull/1732)
+   [aslakhellesoy])
+
 ### Changed
 
 ### Deprecated

monaco/javascript/example/index.html

@@ -5,6 +5,17 @@
     <title>Cucumber Monaco</title>
 </head>
 <body>
+<h1>
+    Monaco Editor with Cucumber Plugin
+</h1>
+<p>
+    Things you can try:
+</p>
+<ul>
+    <li>⇧⌥F - Format Document</li>
+    <li>Modify the first step and see it underlined as undefined</li>
+    <li>Type a new step and see auto-complete suggestions</li>
+</ul>
 <script src="./main.bundle.js"></script>
 </body>
 </html>

monaco/javascript/example/index.js

@@ -38,6 +38,8 @@ Feature: Hello
   Scenario: Hi
     Given I have 58 cukes in my belly
     And this is an undefined step
+      | some | poorly |
+      | formatted | table |
 `,
   language: 'gherkin',
   theme: 'vs-dark',

monaco/javascript/src/index.ts

@@ -3,6 +3,7 @@ import {
   getGherkinCompletionItems,
   getGherkinDiagnostics,
   getGherkinSemanticTokens,
+  getGherkinFormattingEdits,
   semanticTokenModifiers,
   semanticTokenTypes
 } from '@cucumber/language-service'
@@ -85,4 +86,21 @@ export function configure(monaco: Monaco, index: Index | undefined, expressions:
       }
     }
   })
+
+  // Document Formatting
+  monaco.languages.registerDocumentFormattingEditProvider('gherkin', {
+    provideDocumentFormattingEdits: function (model) {
+      const gherkinSource = model.getValue()
+      const textEdits = getGherkinFormattingEdits(gherkinSource)
+      return textEdits.map(textEdit => ({
+        range: {
+          startLineNumber: textEdit.range.start.line + 1,
+          startColumn: textEdit.range.start.character + 1,
+          endLineNumber: textEdit.range.end.line + 1,
+          endColumn: textEdit.range.end.character + 1,
+        },
+        text: textEdit.newText
+      }))
+    }
+  })
 }