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Codemirror on Angular for SQL hints works but gives Typescript typing error


Attaching Stackblitz: https://stackblitz.com/edit/angular-ivy-vxm6gg?file=src/app/app.component.ts

I am trying to implement CodeMirror in Angular 10 for SQL hints as here: https://codemirror.net/mode/sql/. The functionality works correctly on the webpage, and I can also see the correct options in the console log. But, I also see this error not assignable to type 'ShowHintOptions' because I am incorrectly setting the hintOptions option. I haven't found any alternative examples, and my attempts to follow the correct typing were unsuccessful. Please help.

Installation npm install codemirror @types/codemirror

Code

// imports
import * as codemirror from 'codemirror';
import 'codemirror/mode/sql/sql';
import 'codemirror/addon/hint/show-hint';
import 'codemirror/addon/hint/sql-hint';

// Element Ref for this HTML <textarea #ref></textarea>
@ViewChild('ref', { static: true }) ref: ElementRef; 
editor: CodeMirror.EditorFromTextArea;

ngOnInit(): void {
  this.editor = codemirror.fromTextArea(this.ref.nativeElement, {
    mode: 'text/x-mysql',
    showHint: true,
    extraKeys: { 'Ctrl-Space': 'autocomplete' },
    hintOptions: {
      tables: {
        'users': ['name', 'score', 'birthDate'],
        'countries': ['name', 'population', 'size']
      }
    }
  });
  console.log(this.editor.getOption('hintOptions'));
}

Error

 error TS2322: Type '{ tables: { users: string[]; countries: string[]; }; }' is not assignable to type 'ShowHintOptions'.
      Object literal may only specify known properties, and 'tables' does not exist in type 'ShowHintOptions'.
    
    42           tables: {
                 ~~~~~~~~~
    43             'users': ['name', 'score', 'birthDate'],
       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    44             'countries': ['name', 'population', 'size']
       ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    45           }
       ~~~~~~~~~~~
    
      node_modules/@types/codemirror/addon/hint/show-hint.d.ts:81:9
        81         hintOptions?: ShowHintOptions;
                   ~~~~~~~~~~~
        The expected type comes from property 'hintOptions' which is declared here on type 'EditorConfiguration'

Solution

  • Got a workaround to resolve the error.

    Add a variable of any type to hold the values.

    const options: any = {
      tables: {
        users: ["name", "score", "birthDate"],
        countries: ["name", "population", "size"]
      }
    };
    

    Cast the variable as ShowHintOptions

    hintOptions: options as codemirror.ShowHintOptions,

    New code

    ngOnInit(): void {
     const options: any = {
      tables: {
        users: ["name", "score", "birthDate"],
        countries: ["name", "population", "size"]
      }
    };
    this.editor = codemirror.fromTextArea(this.ref.nativeElement, {
      mode: "text/x-mysql",
      hintOptions: options as codemirror.ShowHintOptions,
      extraKeys: { "Ctrl-Space": "autocomplete" }
    });
    console.log(this.editor.getOption('hintOptions'));
    }