chore(cli-repl): MONGOSH-377 separate out autocompleter into its own lerna package (#389)

Co-authored-by: Anna Henningsen <[email protected]>

Author: lrlna

packages/autocomplete/.eslintignore

@@ -0,0 +1,2 @@
+node_modules
+lib/

packages/autocomplete/.eslintrc.js

@@ -0,0 +1 @@
+module.exports = require('../../config/eslintrc.base');

packages/autocomplete/.gitignore

@@ -0,0 +1 @@
+lib/

packages/autocomplete/README.md

@@ -0,0 +1,50 @@
+# `@mongosh/autocomplete`
+
+Package for [MongoDB Shell](mongosh)
+
+## Usage
+
+```js
+const autocomplete = require('@mongosh/autocomplete');
+const serverVersion = '4.4.0';
+const line = 'db.coll.fin';
+const completions = autocomplete(serverVersion, line);
+if (!completions || !completions.length) {
+  return [];
+}
+const entries = completions[0].map((completion) => {
+  return {
+    completion
+  };
+});
+```
+### API
+
+#### completions = autocomplete(serverVersion, line)
+__serverVersion:__ current version of MongoDB
+__line:__ current line to autcomplete
+
+Returns an array of completions, and the line we were autocompleting. For
+example:
+
+```js
+const autocomplete = require('@mongosh/autocomplete');
+const serverVersion = '4.4.0';
+const line = 'db.coll.re';
+const completions = autocomplete(serverVersion, line);
+// returns:
+// [
+//   [ 'db.coll.renameCollection', 'db.coll.replaceOne', 'db.coll.reIndex' ],
+//   'db.coll.re' 
+// ]
+```
+
+Autocomplete is based on currently implemeted APIs in [@mongosh/shell-api](https://www.npmjs.com/package/@mongosh/shell-api)
+
+
+## Installation
+```shell
+npm install -S @mongosh/errors
+```
+
+[mongosh]: https://github.com/mongodb-js/mongosh

packages/cli-repl/src/completer.spec.ts renamed to packages/autocomplete/index.spec.ts

@@ -1,4 +1,4 @@
-import completer from './completer';
+import completer from './';
 import { signatures as shellSignatures } from '@mongosh/shell-api';
 
 import { expect } from 'chai';

packages/cli-repl/src/completer.ts renamed to packages/autocomplete/index.ts

@@ -17,7 +17,7 @@ const BASE_COMPLETIONS = EXPRESSION_OPERATORS.concat(
 const MATCH_COMPLETIONS = QUERY_OPERATORS.concat(BSON_TYPES);
 
 /**
- * The proect stage operator.
+ * The project stage operator.
  */
 const PROJECT = '$project';
 
@@ -29,7 +29,8 @@ const GROUP = '$group';
 /**
  * Return complete suggestions given currently typed line
  *
- * @param {string} Line - Current user input.
+ * @param {string} mdbVersion - Current mongoDB version.
+ * @param {string} line - Current user input.
  *
  * @returns {array} Matching Completions, Current User Input.
  */
@@ -78,7 +79,7 @@ function completer(mdbVersion: string, line: string): [string[], string] {
         expressions = BASE_COMPLETIONS.concat(getStageAccumulators(
           elToComplete, mdbVersion));
       } else {
-        // collection quering just needs MATCH COMPLETIONS
+        // collection querying just needs MATCH COMPLETIONS
         expressions = MATCH_COMPLETIONS;
       }
       // split on {, as a stage/query will always follow an open curly brace
@@ -128,8 +129,7 @@ function filterQueries(mdbVersion: string, completions: any, prefix: string, spl
     return e.name.startsWith(prefix) && semver.gte(mdbVersion, e.version);
   });
 
-  const adjusted = hits.map(h => `${split}${h.name}`);
-  return adjusted;
+  return hits.map(h => `${split}${h.name}`);
 }
 
 function filterShellAPI(mdbVersion: string, completions: object, prefix: string, split?: string[]): any {
@@ -141,8 +141,7 @@ function filterShellAPI(mdbVersion: string, completions: object, prefix: string,
   });
 
   if (split) {
-    const adjusted = hits.map(h => `${split.slice(0, -1).join('.')}.${h}`);
-    return adjusted;
+    return hits.map(h => `${split.slice(0, -1).join('.')}.${h}`);
   }
 
   return hits;