Fix (graphql-language-service) Hover for first line

packages/graphql-language-service-server/src/__tests__/GraphQLLanguageService.test.ts

@@ -12,7 +12,7 @@ import { join } from 'node:path';
 import { GraphQLConfig } from 'graphql-config';
 import { GraphQLLanguageService } from '../GraphQLLanguageService';
 import { SymbolKind } from 'vscode-languageserver-protocol';
-import { Position } from 'graphql-language-service';
+import { getRange, Position } from 'graphql-language-service';
 import { NoopLogger } from '../Logger';
 import { GraphQLEnumType } from 'graphql';
 
@@ -207,6 +207,7 @@ describe('GraphQLLanguageService', () => {
     );
     expect(definitionQueryResult?.definitions.length).toEqual(1);
   });
+
   it('runs definition service on fragment spread', async () => {
     const definitionQueryResult = await languageService.getDefinition(
       'fragment TestFragment on Human { name }\nquery { ...TestFragment }',
@@ -236,6 +237,24 @@ describe('GraphQLLanguageService', () => {
     expect(definitionQueryResult?.definitions.length).toEqual(1);
   });
 
+  it('can get range on first line', async () => {
+    const range = await getRange(
+      { line: 0, column: 15 },
+      `query myHero($id: ID) {
+          hero(id: $id) {
+            name
+            id
+          }
+        }
+    `,
+    );
+
+    expect(range).toMatchObject({
+      end: { character: 23, line: -1 },
+      start: { character: 22, line: -1 },
+    });
+  });
+
   it('runs hover service as expected', async () => {
     const hoverInformation = await languageService.getHoverInformation(
       'type Query { hero(episode: String): String }',

packages/graphql-language-service/src/interface/getDiagnostics.ts

@@ -181,7 +181,12 @@ export function getRange(location: SourceLocation, queryText: string): IRange {
 
   let stream = null;
 
-  for (let i = 0; i < location.line; i++) {
+  // LSP may count from 1, but monaco counts from 0
+  for (
+    let i = 0;
+    location.line === 0 ? i <= location.line : i < location.line;
+    i++
+  ) {
     stream = new CharacterStream(lines[i]);
     while (!stream.eol()) {
       const style = parser.token(stream, state);

packages/graphql-language-service/src/parser/CharacterStream.ts

@@ -46,7 +46,12 @@ export default class CharacterStream implements CharacterStreamInterface {
     return isMatched;
   }
 
-  public eol = (): boolean => this._sourceText.length === this._pos;
+  public eol = (): boolean => {
+    if (!this._sourceText) {
+      return true;
+    }
+    return this._sourceText.length === this._pos;
+  };
 
   public sol = (): boolean => this._pos === 0;