Fixed deprecation warnings on webpack@5.

src/index.ts

@@ -632,6 +632,7 @@ function getTranspilationEmit(
     reportDiagnostics: true,
     fileName,
   });
+  const module = loaderContext._module;
 
   addDependenciesFromSolutionBuilder(instance, fileName, file =>
     loaderContext.addDependency(path.resolve(file))
@@ -644,11 +645,19 @@ function getTranspilationEmit(
       instance.loaderOptions,
       instance.colors,
       instance.compiler,
-      { module: loaderContext._module },
+      { module },
       loaderContext.context
     );
 
-    loaderContext._module.errors.push(...errors);
+    /**
+     * Since webpack 5, the `errors` property is deprecated,
+     * so we can check if some methods for reporting errors exist.
+     */
+    if (!!module.addError) {
+      errors.forEach(error => module.addError(error));
+    } else {
+      module.errors.push(...errors);
+    }
   }
 
   return { outputText, sourceMapText };

src/instances.ts

@@ -146,6 +146,7 @@ function successfulTypeScriptInstance(
     }
   }
 
+  const module = loader._module;
   const basePath = loaderOptions.context || path.dirname(configFilePath || '');
   const configParseResult = getConfigParseResult(
     compiler,
@@ -165,7 +166,15 @@ function successfulTypeScriptInstance(
       loader.context
     );
 
-    loader._module.errors.push(...errors);
+    /**
+     * Since webpack 5, the `errors` property is deprecated,
+     * so we can check if some methods for reporting errors exist.
+     */
+    if (!!module.addError) {
+      errors.forEach(error => module.addError(error));
+    } else {
+      module.errors.push(...errors);
+    }
 
     return {
       error: makeError(
@@ -415,6 +424,7 @@ export function reportTranspileErrors(
   if (!instance.reportTranspileErrors) {
     return;
   }
+  const module = loader._module;
   instance.reportTranspileErrors = false;
   // happypack does not have _module.errors - see https://github.com/TypeStrong/ts-loader/issues/336
   if (!instance.loaderOptions.happyPackMode) {
@@ -431,7 +441,15 @@ export function reportTranspileErrors(
       { file: instance.configFilePath || 'tsconfig.json' },
       loader.context
     );
-    loader._module.errors.push(...solutionErrors, ...errors);
+    /**
+     * Since webpack 5, the `errors` property is deprecated,
+     * so we can check if some methods for reporting errors exist.
+     */
+    if (!!module.addError) {
+      [...solutionErrors, ...errors].forEach(error => module.addError(error));
+    } else {
+      module.errors.push(...solutionErrors, ...errors);
+    }
   }
 }