[ES|QL] Add improved support for Elasticsearch sub-types in AST for b…

…oth validation and autocomplete (elastic#188600)

## Summary

This PR addresses elastic#174710 and
leverages sub-types in AST for both validation and autocomplete. Changes
include:
- Expanded the automatically generated function signatures to not longer
cast to `string` or `number`. Instead, it expands out to `keyword`,
`text`, `double`, `long`, `float`, etc.
- Expanded math function signatures to reflect the true return types
(e.g double + interger => double)
- Expanded function signatures for `bucket`
- Expanded builtin functions to better support types
-  Literal support: 
- Added a `decimal` literal context → Which will be accepted by function
signatures for 'double', 'long', 'float', etc.
- Added and `integer` literal type → Which will be accepted by function
signatures for 'interger'
- Updated tests

After:
<img width="1181" alt="Screenshot 2024-07-24 at 13 06 23"
src="https://github.com/user-attachments/assets/42f32f3b-2e6e-4dff-8b20-dd60f8c45750">
<img width="1726" alt="Screenshot 2024-07-24 at 13 06 47"
src="https://github.com/user-attachments/assets/3c6f1eac-600e-4b2c-9e57-f71f79ad9ce9">
<img width="1726" alt="Screenshot 2024-07-24 at 13 07 09"
src="https://github.com/user-attachments/assets/e8b5817e-d4de-446b-8b41-c6c7b8612420">

### Checklist

Delete any items that are not applicable to this PR.

- [ ] Any text added follows [EUI's writing
guidelines](https://elastic.github.io/eui/#/guidelines/writing), uses
sentence case text and includes [i18n
support](https://github.com/elastic/kibana/blob/main/packages/kbn-i18n/README.md)
- [ ]
[Documentation](https://www.elastic.co/guide/en/kibana/master/development-documentation.html)
was added for features that require explanation or tutorials
- [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
- [ ] [Flaky Test
Runner](https://ci-stats.kibana.dev/trigger_flaky_test_runner/1) was
used on any tests changed
- [ ] Any UI touched in this PR is usable by keyboard only (learn more
about [keyboard accessibility](https://webaim.org/techniques/keyboard/))
- [ ] Any UI touched in this PR does not create any new axe failures
(run axe in browser:
[FF](https://addons.mozilla.org/en-US/firefox/addon/axe-devtools/),
[Chrome](https://chrome.google.com/webstore/detail/axe-web-accessibility-tes/lhdoppojpmngadmnindnejefpokejbdd?hl=en-US))
- [ ] If a plugin configuration key changed, check if it needs to be
allowlisted in the cloud and added to the [docker
list](https://github.com/elastic/kibana/blob/main/src/dev/build/tasks/os_packages/docker_generator/resources/base/bin/kibana-docker)
- [ ] This renders correctly on smaller devices using a responsive
layout. (You can test this [in your
browser](https://www.browserstack.com/guide/responsive-testing-on-local-server))
- [ ] This was checked for [cross-browser
compatibility](https://www.elastic.co/support/matrix#matrix_browsers)


### Risk Matrix

Delete this section if it is not applicable to this PR.

Before closing this PR, invite QA, stakeholders, and other developers to
identify risks that should be tested prior to the change/feature
release.

When forming the risk matrix, consider some of the following examples
and how they may potentially impact the change:

| Risk | Probability | Severity | Mitigation/Notes |

|---------------------------|-------------|----------|-------------------------|
| Multiple Spaces&mdash;unexpected behavior in non-default Kibana Space.
| Low | High | Integration tests will verify that all features are still
supported in non-default Kibana Space and when user switches between
spaces. |
| Multiple nodes&mdash;Elasticsearch polling might have race conditions
when multiple Kibana nodes are polling for the same tasks. | High | Low
| Tasks are idempotent, so executing them multiple times will not result
in logical error, but will degrade performance. To test for this case we
add plenty of unit tests around this logic and document manual testing
procedure. |
| Code should gracefully handle cases when feature X or plugin Y are
disabled. | Medium | High | Unit tests will verify that any feature flag
or plugin combination still results in our service operational. |
| [See more potential risk
examples](https://github.com/elastic/kibana/blob/main/RISK_MATRIX.mdx) |


### For maintainers

- [ ] This was checked for breaking API changes and was [labeled
appropriately](https://www.elastic.co/guide/en/kibana/master/contributing.html#kibana-release-notes-process)

---------

Co-authored-by: kibanamachine <42973632+kibanamachine@users.noreply.github.com>
Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

packages/kbn-esql-ast/src/ast_factory.ts

@@ -205,7 +205,7 @@ export class AstListener implements ESQLParserListener {
     const command = createCommand('limit', ctx);
     this.ast.push(command);
     if (ctx.getToken(esql_parser.INTEGER_LITERAL, 0)) {
-      const literal = createLiteral('number', ctx.INTEGER_LITERAL());
+      const literal = createLiteral('integer', ctx.INTEGER_LITERAL());
       if (literal) {
         command.args.push(literal);
       }

packages/kbn-esql-ast/src/ast_helpers.ts

@@ -35,7 +35,9 @@ import type {
   ESQLCommandMode,
   ESQLInlineCast,
   ESQLUnknownItem,
+  ESQLNumericLiteralType,
   FunctionSubtype,
+  ESQLNumericLiteral,
 } from './types';
 
 export function nonNullable<T>(v: T): v is NonNullable<T> {
@@ -87,11 +89,14 @@ export function createList(ctx: ParserRuleContext, values: ESQLLiteral[]): ESQLL
   };
 }
 
-export function createNumericLiteral(ctx: DecimalValueContext | IntegerValueContext): ESQLLiteral {
+export function createNumericLiteral(
+  ctx: DecimalValueContext | IntegerValueContext,
+  literalType: ESQLNumericLiteralType
+): ESQLLiteral {
   const text = ctx.getText();
   return {
     type: 'literal',
-    literalType: 'number',
+    literalType,
     text,
     name: text,
     value: Number(text),
@@ -100,10 +105,13 @@ export function createNumericLiteral(ctx: DecimalValueContext | IntegerValueCont
   };
 }
 
-export function createFakeMultiplyLiteral(ctx: ArithmeticUnaryContext): ESQLLiteral {
+export function createFakeMultiplyLiteral(
+  ctx: ArithmeticUnaryContext,
+  literalType: ESQLNumericLiteralType
+): ESQLLiteral {
   return {
     type: 'literal',
-    literalType: 'number',
+    literalType,
     text: ctx.getText(),
     name: ctx.getText(),
     value: ctx.PLUS() ? 1 : -1,
@@ -158,20 +166,21 @@ export function createLiteral(
     location: getPosition(node.symbol),
     incomplete: isMissingText(text),
   };
-  if (type === 'number') {
+  if (type === 'decimal' || type === 'integer') {
     return {
       ...partialLiteral,
       literalType: type,
       value: Number(text),
-    };
+      paramType: 'number',
+    } as ESQLNumericLiteral<'decimal'> | ESQLNumericLiteral<'integer'>;
   } else if (type === 'param') {
     throw new Error('Should never happen');
   }
   return {
     ...partialLiteral,
     literalType: type,
     value: text,
-  };
+  } as ESQLLiteral;
 }
 
 export function createTimeUnit(ctx: QualifiedIntegerLiteralContext): ESQLTimeInterval {

packages/kbn-esql-ast/src/ast_walker.ts

@@ -84,7 +84,7 @@ import {
   createUnknownItem,
 } from './ast_helpers';
 import { getPosition } from './ast_position_utils';
-import type {
+import {
   ESQLLiteral,
   ESQLColumn,
   ESQLFunction,
@@ -289,7 +289,7 @@ function visitOperatorExpression(
     const arg = visitOperatorExpression(ctx.operatorExpression());
     // this is a number sign thing
     const fn = createFunction('*', ctx, undefined, 'binary-expression');
-    fn.args.push(createFakeMultiplyLiteral(ctx));
+    fn.args.push(createFakeMultiplyLiteral(ctx, 'integer'));
     if (arg) {
       fn.args.push(arg);
     }
@@ -328,16 +328,21 @@ function getConstant(ctx: ConstantContext): ESQLAstItem {
     // e.g. 1 year, 15 months
     return createTimeUnit(ctx);
   }
+
+  // Decimal type covers multiple ES|QL types: long, double, etc.
   if (ctx instanceof DecimalLiteralContext) {
-    return createNumericLiteral(ctx.decimalValue());
+    return createNumericLiteral(ctx.decimalValue(), 'decimal');
   }
+
+  // Integer type encompasses integer
   if (ctx instanceof IntegerLiteralContext) {
-    return createNumericLiteral(ctx.integerValue());
+    return createNumericLiteral(ctx.integerValue(), 'integer');
   }
   if (ctx instanceof BooleanLiteralContext) {
     return getBooleanValue(ctx);
   }
   if (ctx instanceof StringLiteralContext) {
+    // String literal covers multiple ES|QL types: text and keyword types
     return createLiteral('string', ctx.string_().QUOTED_STRING());
   }
   if (
@@ -346,14 +351,18 @@ function getConstant(ctx: ConstantContext): ESQLAstItem {
     ctx instanceof StringArrayLiteralContext
   ) {
     const values: ESQLLiteral[] = [];
+
     for (const numericValue of ctx.getTypedRuleContexts(NumericValueContext)) {
+      const isDecimal =
+        numericValue.decimalValue() !== null && numericValue.decimalValue() !== undefined;
       const value = numericValue.decimalValue() || numericValue.integerValue();
-      values.push(createNumericLiteral(value!));
+      values.push(createNumericLiteral(value!, isDecimal ? 'decimal' : 'integer'));
     }
     for (const booleanValue of ctx.getTypedRuleContexts(BooleanValueContext)) {
       values.push(getBooleanValue(booleanValue)!);
     }
     for (const string of ctx.getTypedRuleContexts(StringContext)) {
+      // String literal covers multiple ES|QL types: text and keyword types
       const literal = createLiteral('string', string.QUOTED_STRING());
       if (literal) {
         values.push(literal);

packages/kbn-esql-ast/src/types.ts

@@ -179,19 +179,30 @@ export interface ESQLList extends ESQLAstBaseItem {
   values: ESQLLiteral[];
 }
 
+export type ESQLNumericLiteralType = 'decimal' | 'integer';
+
 export type ESQLLiteral =
-  | ESQLNumberLiteral
+  | ESQLDecimalLiteral
+  | ESQLIntegerLiteral
   | ESQLBooleanLiteral
   | ESQLNullLiteral
   | ESQLStringLiteral
   | ESQLParamLiteral<string>;
 
+// Exporting here to prevent TypeScript error TS4058
+// Return type of exported function has or is using name 'ESQLNumericLiteral' from external module
 // @internal
-export interface ESQLNumberLiteral extends ESQLAstBaseItem {
+export interface ESQLNumericLiteral<T extends ESQLNumericLiteralType> extends ESQLAstBaseItem {
   type: 'literal';
-  literalType: 'number';
+  literalType: T;
   value: number;
 }
+// We cast anything as decimal (e.g. 32.12) as generic decimal numeric type here
+// @internal
+export type ESQLDecimalLiteral = ESQLNumericLiteral<'decimal'>;
+
+// @internal
+export type ESQLIntegerLiteral = ESQLNumericLiteral<'integer'>;
 
 // @internal
 export interface ESQLBooleanLiteral extends ESQLAstBaseItem {

packages/kbn-esql-ast/src/walker/walker.test.ts

@@ -211,7 +211,7 @@ describe('structurally can walk all nodes', () => {
           expect(columns).toMatchObject([
             {
               type: 'literal',
-              literalType: 'number',
+              literalType: 'integer',
               name: '123',
             },
             {
@@ -244,7 +244,7 @@ describe('structurally can walk all nodes', () => {
           expect(columns).toMatchObject([
             {
               type: 'literal',
-              literalType: 'number',
+              literalType: 'integer',
               name: '1',
             },
             {
@@ -264,7 +264,7 @@ describe('structurally can walk all nodes', () => {
             },
             {
               type: 'literal',
-              literalType: 'number',
+              literalType: 'decimal',
               name: '3.14',
             },
           ]);
@@ -288,12 +288,12 @@ describe('structurally can walk all nodes', () => {
                 values: [
                   {
                     type: 'literal',
-                    literalType: 'number',
+                    literalType: 'integer',
                     name: '1',
                   },
                   {
                     type: 'literal',
-                    literalType: 'number',
+                    literalType: 'integer',
                     name: '2',
                   },
                 ],
@@ -318,12 +318,12 @@ describe('structurally can walk all nodes', () => {
                 values: [
                   {
                     type: 'literal',
-                    literalType: 'number',
+                    literalType: 'integer',
                     name: '1',
                   },
                   {
                     type: 'literal',
-                    literalType: 'number',
+                    literalType: 'integer',
                     name: '2',
                   },
                 ],
@@ -333,7 +333,7 @@ describe('structurally can walk all nodes', () => {
                 values: [
                   {
                     type: 'literal',
-                    literalType: 'number',
+                    literalType: 'decimal',
                     name: '3.3',
                   },
                 ],
@@ -342,17 +342,17 @@ describe('structurally can walk all nodes', () => {
             expect(literals).toMatchObject([
               {
                 type: 'literal',
-                literalType: 'number',
+                literalType: 'integer',
                 name: '1',
               },
               {
                 type: 'literal',
-                literalType: 'number',
+                literalType: 'integer',
                 name: '2',
               },
               {
                 type: 'literal',
-                literalType: 'number',
+                literalType: 'decimal',
                 name: '3.3',
               },
             ]);
@@ -511,7 +511,7 @@ describe('structurally can walk all nodes', () => {
 
       describe('cast expression', () => {
         test('can visit cast expression', () => {
-          const query = 'FROM index | STATS a = 123::number';
+          const query = 'FROM index | STATS a = 123::integer';
           const { ast } = getAstAndSyntaxErrors(query);
 
           const casts: ESQLInlineCast[] = [];
@@ -523,10 +523,10 @@ describe('structurally can walk all nodes', () => {
           expect(casts).toMatchObject([
             {
               type: 'inlineCast',
-              castType: 'number',
+              castType: 'integer',
               value: {
                 type: 'literal',
-                literalType: 'number',
+                literalType: 'integer',
                 value: 123,
               },
             },

packages/kbn-esql-validation-autocomplete/scripts/generate_function_definitions.ts

@@ -12,7 +12,6 @@ import { join } from 'path';
 import _ from 'lodash';
 import type { RecursivePartial } from '@kbn/utility-types';
 import { FunctionDefinition } from '../src/definitions/types';
-import { esqlToKibanaType } from '../src/shared/esql_to_kibana_type';
 
 const aliasTable: Record<string, string[]> = {
   to_version: ['to_ver'],
@@ -240,10 +239,10 @@ function getFunctionDefinition(ESFunctionDefinition: Record<string, any>): Funct
         ...signature,
         params: signature.params.map((param: any) => ({
           ...param,
-          type: esqlToKibanaType(param.type),
+          type: param.type,
           description: undefined,
         })),
-        returnType: esqlToKibanaType(signature.returnType),
+        returnType: signature.returnType,
         variadic: undefined, // we don't support variadic property
         minParams: signature.variadic
           ? signature.params.filter((param: any) => !param.optional).length