[ES|QL] Separate RENAME autocomplete routine (#213641)

## Summary

Part of https://github.com/elastic/kibana/issues/195418

Gives `RENAME` autocomplete logic its own home 🏡

### Checklist

- [x] [Unit or functional
tests](https://www.elastic.co/guide/en/kibana/master/development-tests.html)
were updated or added to match the most common scenarios

### Identify risks

- [ ] As with any refactor, there's a possibility this will introduce a
regression in the behavior of commands. However, all automated tests are
passing and I have tested the behavior manually and can detect no
regression.

src/platform/packages/shared/kbn-esql-validation-autocomplete/src/autocomplete/__tests__/autocomplete.command.rename.test.ts

@@ -0,0 +1,53 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+import { getFieldNamesByType, setup } from './helpers';
+
+describe('autocomplete.suggest', () => {
+  describe('RENAME', () => {
+    it('suggests fields', async () => {
+      const { assertSuggestions } = await setup();
+      await assertSuggestions(
+        'from a | rename /',
+        getFieldNamesByType('any').map((field) => field + ' ')
+      );
+      await assertSuggestions(
+        'from a | rename fie/',
+        getFieldNamesByType('any').map((field) => field + ' ')
+      );
+      await assertSuggestions(
+        'from a | rename field AS foo, /',
+        getFieldNamesByType('any').map((field) => field + ' ')
+      );
+      await assertSuggestions(
+        'from a | rename field AS foo, fie/',
+        getFieldNamesByType('any').map((field) => field + ' ')
+      );
+    });
+
+    it('suggests AS after field', async () => {
+      const { assertSuggestions } = await setup();
+      await assertSuggestions('from a | rename field /', ['AS ']);
+      await assertSuggestions('from a | rename field A/', ['AS ']);
+      await assertSuggestions('from a | rename field AS foo, field2 /', ['AS ']);
+      await assertSuggestions('from a | rename field as foo , field2 /', ['AS ']);
+      await assertSuggestions('from a | rename field AS foo, field2 A/', ['AS ']);
+    });
+
+    it('suggests nothing after AS', async () => {
+      const { assertSuggestions } = await setup();
+      await assertSuggestions('from a | rename field AS /', []);
+    });
+
+    it('suggests pipe and comma after complete expression', async () => {
+      const { assertSuggestions } = await setup();
+      await assertSuggestions('from a | rename field AS foo /', ['| ', ', ']);
+    });
+  });
+});

src/platform/packages/shared/kbn-esql-validation-autocomplete/src/autocomplete/autocomplete.test.ts

@@ -112,12 +112,6 @@ describe('autocomplete', () => {
     testSuggestions('from a metadata _id | eval var0 = a | /', commands);
   });
 
-  describe('rename', () => {
-    testSuggestions('from a | rename /', getFieldNamesByType('any'));
-    testSuggestions('from a | rename keywordField /', ['AS $0'], ' ');
-    testSuggestions('from a | rename keywordField as /', ['var0']);
-  });
-
   for (const command of ['keep', 'drop']) {
     describe(command, () => {
       testSuggestions(`from a | ${command} /`, getFieldNamesByType('any'));
@@ -405,13 +399,13 @@ describe('autocomplete', () => {
     );
 
     // RENAME field
-    testSuggestions('FROM index1 | RENAME f/', getFieldNamesByType('any'));
+    testSuggestions(
+      'FROM index1 | RENAME f/',
+      getFieldNamesByType('any').map((name) => `${name} `)
+    );
 
     // RENAME field AS
-    testSuggestions('FROM index1 | RENAME field A/', ['AS $0']);
-
-    // RENAME field AS var0
-    testSuggestions('FROM index1 | RENAME field AS v/', ['var0']);
+    testSuggestions('FROM index1 | RENAME field A/', ['AS ']);
 
     // STATS argument
     testSuggestions('FROM index1 | STATS f/', [

src/platform/packages/shared/kbn-esql-validation-autocomplete/src/autocomplete/autocomplete.ts

@@ -22,7 +22,6 @@ import type { EditorContext, ItemKind, SuggestionRawDefinition, GetColumnsByType
 import {
   getColumnForASTNode,
   getCommandDefinition,
-  getCommandOption,
   getFunctionDefinition,
   isAssignment,
   isAssignmentComplete,
@@ -36,7 +35,6 @@ import {
   isTimeIntervalItem,
   getAllFunctions,
   isSingleItem,
-  nonNullable,
   getColumnExists,
   findPreviousWord,
   correctQuerySyntax,
@@ -59,7 +57,6 @@ import {
   getFunctionSuggestions,
   getCompatibleLiterals,
   buildConstantsDefinitions,
-  buildVariablesDefinitions,
   buildOptionDefinition,
   buildValueDefinitions,
   getDateLiterals,
@@ -172,13 +169,7 @@ export async function suggest(
     return suggestions.filter((def) => !isSourceCommand(def));
   }
 
-  if (
-    astContext.type === 'expression' ||
-    (astContext.type === 'option' && astContext.command?.name === 'join') ||
-    (astContext.type === 'option' && astContext.command?.name === 'dissect') ||
-    (astContext.type === 'option' && astContext.command?.name === 'from') ||
-    (astContext.type === 'option' && astContext.command?.name === 'enrich')
-  ) {
+  if (astContext.type === 'expression') {
     return getSuggestionsWithinCommandExpression(
       innerText,
       ast,
@@ -194,20 +185,6 @@ export async function suggest(
       supportsControls
     );
   }
-  if (astContext.type === 'option') {
-    // need this wrap/unwrap thing to make TS happy
-    const { option, ...rest } = astContext;
-    if (option && isOptionItem(option)) {
-      return getOptionArgsSuggestions(
-        innerText,
-        ast,
-        { option, ...rest },
-        getFieldsByType,
-        getFieldsMap,
-        getPolicyMetadata
-      );
-    }
-  }
   if (astContext.type === 'function') {
     return getFunctionArgsSuggestions(
       innerText,
@@ -1190,71 +1167,3 @@ async function getListArgsSuggestions(
   }
   return suggestions;
 }
-
-/**
- * @deprecated — this will disappear when https://github.com/elastic/kibana/issues/195418 is complete
- * because "options" will be handled in imperative command-specific routines instead of being independent.
- */
-async function getOptionArgsSuggestions(
-  innerText: string,
-  commands: ESQLCommand[],
-  {
-    command,
-    option,
-    node,
-  }: {
-    command: ESQLCommand;
-    option: ESQLCommandOption;
-    node: ESQLSingleAstItem | undefined;
-  },
-  getFieldsByType: GetColumnsByTypeFn,
-  getFieldsMaps: GetFieldsMapFn,
-  getPolicyMetadata: GetPolicyMetadataFn
-) {
-  const optionDef = getCommandOption(option.name);
-  if (!optionDef || !optionDef.signature) {
-    return [];
-  }
-  const { nodeArg, lastArg } = extractArgMeta(option, node);
-  const suggestions = [];
-  const isNewExpression = isRestartingExpression(innerText) || option.args.length === 0;
-
-  const fieldsMap = await getFieldsMaps();
-  const anyVariables = collectVariables(commands, fieldsMap, innerText);
-
-  if (command.name === 'rename') {
-    if (option.args.length < 2) {
-      suggestions.push(...buildVariablesDefinitions([findNewVariable(anyVariables)]));
-    }
-  }
-
-  if (optionDef) {
-    if (!suggestions.length) {
-      const argDefIndex = optionDef.signature.multipleParams
-        ? 0
-        : Math.max(option.args.length - 1, 0);
-      const types = [optionDef.signature.params[argDefIndex].type].filter(nonNullable);
-      // If it's a complete expression then proposed some final suggestions
-      // A complete expression is either a function or a column: <COMMAND> <OPTION> field <here>
-      // Or an assignment complete: <COMMAND> <OPTION> field = ... <here>
-      if (
-        (option.args.length && !isNewExpression && !isAssignment(lastArg)) ||
-        (isAssignment(lastArg) && isAssignmentComplete(lastArg))
-      ) {
-        suggestions.push(
-          ...getFinalSuggestions({
-            comma: optionDef.signature.multipleParams,
-          })
-        );
-      } else if (isNewExpression || (isAssignment(nodeArg) && !isAssignmentComplete(nodeArg))) {
-        suggestions.push(
-          ...(await getFieldsByType(types[0] === 'column' ? ['any'] : types, [], {
-            advanceCursor: true,
-            openSuggestions: true,
-          }))
-        );
-      }
-    }
-  }
-  return suggestions;
-}

src/platform/packages/shared/kbn-esql-validation-autocomplete/src/autocomplete/commands/rename/index.ts

@@ -0,0 +1,43 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the "Elastic License
+ * 2.0", the "GNU Affero General Public License v3.0 only", and the "Server Side
+ * Public License v 1"; you may not use this file except in compliance with, at
+ * your election, the "Elastic License 2.0", the "GNU Affero General Public
+ * License v3.0 only", or the "Server Side Public License, v 1".
+ */
+
+import { i18n } from '@kbn/i18n';
+import { CommandSuggestParams } from '../../../definitions/types';
+
+import type { SuggestionRawDefinition } from '../../types';
+import { commaCompleteItem, pipeCompleteItem } from '../../complete_items';
+
+export async function suggest({
+  getColumnsByType,
+  innerText,
+}: CommandSuggestParams<'rename'>): Promise<SuggestionRawDefinition[]> {
+  if (/(?:rename|,)\s+\S+\s+a?$/i.test(innerText)) {
+    return [asCompletionItem];
+  }
+
+  if (/rename(?:\s+\S+\s+as\s+\S+\s*,)*\s+\S+\s+as\s+[^\s,]+\s+$/i.test(innerText)) {
+    return [pipeCompleteItem, { ...commaCompleteItem, text: ', ' }];
+  }
+
+  if (/as\s+$/i.test(innerText)) {
+    return [];
+  }
+
+  return getColumnsByType('any', [], { advanceCursor: true, openSuggestions: true });
+}
+
+const asCompletionItem: SuggestionRawDefinition = {
+  detail: i18n.translate('kbn-esql-validation-autocomplete.esql.definitions.asDoc', {
+    defaultMessage: 'As',
+  }),
+  kind: 'Reference',
+  label: 'AS',
+  sortText: '1',
+  text: 'AS ',
+};

src/platform/packages/shared/kbn-esql-validation-autocomplete/src/definitions/commands.ts

@@ -42,6 +42,7 @@ import { suggest as suggestForShow } from '../autocomplete/commands/show';
 import { suggest as suggestForGrok } from '../autocomplete/commands/grok';
 import { suggest as suggestForDissect } from '../autocomplete/commands/dissect';
 import { suggest as suggestForEnrich } from '../autocomplete/commands/enrich';
+import { suggest as suggestForRename } from '../autocomplete/commands/rename';
 import { suggest as suggestForLimit } from '../autocomplete/commands/limit';
 import { suggest as suggestForMvExpand } from '../autocomplete/commands/mv_expand';
 
@@ -275,6 +276,7 @@ export const commandDefinitions: Array<CommandDefinition<any>> = [
     },
     options: [asOption],
     modes: [],
+    suggest: suggestForRename,
   },
   {
     name: 'limit',

src/platform/packages/shared/kbn-esql-validation-autocomplete/src/shared/context.ts

@@ -13,19 +13,19 @@ import {
   type ESQLAst,
   type ESQLFunction,
   type ESQLCommand,
-  type ESQLCommandOption,
-  type ESQLCommandMode,
   Walker,
   isIdentifier,
+  ESQLCommandOption,
+  ESQLCommandMode,
 } from '@kbn/esql-ast';
 import { FunctionDefinitionTypes } from '../definitions/types';
 import { EDITOR_MARKER } from './constants';
 import {
-  isOptionItem,
   isColumnItem,
   isSourceItem,
   pipePrecedesCurrentWord,
   getFunctionDefinition,
+  isOptionItem,
 } from './helpers';
 
 function findNode(nodes: ESQLAstItem[], offset: number): ESQLSingleAstItem | undefined {
@@ -119,7 +119,7 @@ export function removeMarkerArgFromArgsList<T extends ESQLSingleAstItem | ESQLCo
 function findAstPosition(ast: ESQLAst, offset: number) {
   const command = findCommand(ast, offset);
   if (!command) {
-    return { command: undefined, node: undefined, option: undefined, setting: undefined };
+    return { command: undefined, node: undefined };
   }
   return {
     command: removeMarkerArgFromArgsList(command)!,
@@ -144,8 +144,6 @@ function isOperator(node: ESQLFunction) {
  * Type details:
  * * "list": the cursor is inside a "in" list of values (i.e. `a in (1, 2, <here>)`)
  * * "function": the cursor is inside a function call (i.e. `fn(<here>)`)
- * * "option": the cursor is inside a command option (i.e. `command ... by <here>`)
- * * "setting": the cursor is inside a setting (i.e. `command _<here>`)
  * * "expression": the cursor is inside a command expression (i.e. `command ... <here>` or `command a = ... <here>`)
  * * "newCommand": the cursor is at the beginning of a new command (i.e. `command1 | command2 | <here>`)
  */
@@ -193,13 +191,6 @@ export function getAstContext(queryString: string, ast: ESQLAst, offset: number)
     return { type: 'newCommand' as const, command: undefined, node, option };
   }
 
-  // TODO — remove this option branch once https://github.com/elastic/kibana/issues/195418 is complete
-  if (command && isOptionItem(command.args[command.args.length - 1]) && command.name !== 'stats') {
-    if (option) {
-      return { type: 'option' as const, command, node, option };
-    }
-  }
-
   // command a ... <here> OR command a = ... <here>
   return {
     type: 'expression' as const,