refactor: use chainable asError/asWarning/asSuggestion for Reporter severity

Author: johnsoncodehk

packages/core/index.ts

@@ -139,9 +139,9 @@ export function createLinter(
 						rule2Mode.set(currentRuleId, true);
 						shouldRetry = true;
 					} else if (err instanceof Error) {
-						report(err.stack ?? err.message, 0, 0, ts.DiagnosticCategory.Message, [err, 0]);
+						report(err.stack ?? err.message, 0, 0, [err, 0]);
 					} else {
-						report(String(err), 0, 0, ts.DiagnosticCategory.Message, [new Error(), Number.MAX_VALUE]);
+						report(String(err), 0, 0, [new Error(), Number.MAX_VALUE]);
 					}
 				}
 
@@ -201,9 +201,9 @@ export function createLinter(
 
 			return diagnostics;
 
-			function report(message: string, start: number, end: number, category: ts.DiagnosticCategory = ts.DiagnosticCategory.Message, reportAt: [Error, number] = [new Error(), 1]): Reporter {
+			function report(message: string, start: number, end: number, reportAt: [Error, number] = [new Error(), 1]): Reporter {
 				const error: ts.DiagnosticWithLocation = {
-					category,
+					category: ts.DiagnosticCategory.Message,
 					code: currentRuleId as any,
 					messageText: message,
 					file: rulesContext.file,
@@ -237,6 +237,18 @@ export function createLinter(
 				const fixes = diagnostic2Fixes.get(error)!;
 
 				return {
+					asWarning() {
+						error.category = ts.DiagnosticCategory.Warning;
+						return this;
+					},
+					asError() {
+						error.category = ts.DiagnosticCategory.Error;
+						return this;
+					},
+					asSuggestion() {
+						error.category = ts.DiagnosticCategory.Suggestion;
+						return this;
+					},
 					withDeprecated() {
 						error.reportsDeprecated = true;
 						return this;

packages/eslint/index.ts

@@ -249,7 +249,16 @@ export function convertRule(
 						}
 					}
 				} catch { }
-				const reporter = report(message, start, end, category, [new Error(), 1]);
+				const reporter = report(message, start, end, [new Error(), 1]);
+				if (category === 0 satisfies ts.DiagnosticCategory.Warning) {
+					reporter.asWarning();
+				}
+				else if (category === 1 satisfies ts.DiagnosticCategory.Error) {
+					reporter.asError();
+				}
+				else if (category === 2 satisfies ts.DiagnosticCategory.Suggestion) {
+					reporter.asSuggestion();
+				}
 				if (descriptor.fix) {
 					// @ts-expect-error
 					const textChanges = getTextChanges(descriptor.fix);

packages/tslint/index.ts

@@ -25,9 +25,17 @@ export function convertRule(
 				failure.getFailure(),
 				failure.getStartPosition().getPosition(),
 				failure.getEndPosition().getPosition(),
-				category,
 				[new Error(), Number.MAX_VALUE]
 			);
+			if (category === 0 satisfies ts.DiagnosticCategory.Warning) {
+				reporter.asWarning();
+			}
+			else if (category === 1 satisfies ts.DiagnosticCategory.Error) {
+				reporter.asError();
+			}
+			else if (category === 2 satisfies ts.DiagnosticCategory.Suggestion) {
+				reporter.asSuggestion();
+			}
 			if (failure.hasFix()) {
 				const ruleName = Rule.metadata?.ruleName;
 				reporter.withFix(

packages/types/index.ts

@@ -1,7 +1,6 @@
 import type {
 	CodeFixAction,
 	Diagnostic,
-	DiagnosticCategory,
 	DiagnosticWithLocation,
 	FileTextChanges,
 	LanguageService,
@@ -45,10 +44,13 @@ export interface RuleContext {
 	typescript: typeof import('typescript');
 	program: Program;
 	file: SourceFile;
-	report(message: string, start: number, end: number, category?: DiagnosticCategory, reportAt?: [Error, number]): Reporter;
+	report(message: string, start: number, end: number, reportAt?: [Error, number]): Reporter;
 }
 
 export interface Reporter {
+	asWarning(): Reporter;
+	asError(): Reporter;
+	asSuggestion(): Reporter;
 	withDeprecated(): Reporter;
 	withUnnecessary(): Reporter;
 	withFix(title: string, getChanges: () => FileTextChanges[]): Reporter;