diff --git a/src/core/sourceType.js b/src/core/sourceType.js
new file mode 100644
index 000000000..4243be4cf
--- /dev/null
+++ b/src/core/sourceType.js
@@ -0,0 +1,7 @@
+/**
+ * @param {import('eslint').Rule.RuleContext} context
+ * @returns 'module' | 'script' | undefined
+ */
+export default function sourceType(context) {
+  return context.parserOptions.sourceType;
+}
diff --git a/src/rules/no-default-export.js b/src/rules/no-default-export.js
index fcb4f1b2f..d18f0c48f 100644
--- a/src/rules/no-default-export.js
+++ b/src/rules/no-default-export.js
@@ -1,6 +1,7 @@
 import { getSourceCode } from 'eslint-module-utils/contextCompat';
 
 import docsUrl from '../docsUrl';
+import sourceType from '../core/sourceType';
 
 module.exports = {
   meta: {
@@ -15,7 +16,7 @@ module.exports = {
 
   create(context) {
     // ignore non-modules
-    if (context.parserOptions.sourceType !== 'module') {
+    if (sourceType(context) !== 'module') {
       return {};
     }
 
diff --git a/src/rules/no-named-export.js b/src/rules/no-named-export.js
index efaf9dc4c..fc9b2c48d 100644
--- a/src/rules/no-named-export.js
+++ b/src/rules/no-named-export.js
@@ -1,3 +1,4 @@
+import sourceType from '../core/sourceType';
 import docsUrl from '../docsUrl';
 
 module.exports = {
@@ -13,7 +14,7 @@ module.exports = {
 
   create(context) {
     // ignore non-modules
-    if (context.parserOptions.sourceType !== 'module') {
+    if (sourceType(context) !== 'module') {
       return {};
     }
 
diff --git a/src/rules/unambiguous.js b/src/rules/unambiguous.js
index 91152ea2a..2491fad3e 100644
--- a/src/rules/unambiguous.js
+++ b/src/rules/unambiguous.js
@@ -5,6 +5,7 @@
 
 import { isModule } from 'eslint-module-utils/unambiguous';
 import docsUrl from '../docsUrl';
+import sourceType from '../core/sourceType';
 
 module.exports = {
   meta: {
@@ -19,7 +20,7 @@ module.exports = {
 
   create(context) {
     // ignore non-modules
-    if (context.parserOptions.sourceType !== 'module') {
+    if (sourceType(context) !== 'module') {
       return {};
     }