diff --git a/dist/index.js b/dist/index.js
index facf8cb..a91707d 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -71,9 +71,9 @@ function parseDirectories(file, depth, targetDirectory) {
 }
 
 function buildMatrix(changedDirectories) {
-    include = [];
-    var directory;
-    for (directory of changedDirectories) {
+    let directories = [...new Set(changedDirectories)];
+    let include = []
+    for (directory of directories) {
         include.push({'directory': directory});
     }
     return {'include': include};
diff --git a/index.js b/index.js
index 9f04890..27ba10a 100644
--- a/index.js
+++ b/index.js
@@ -64,9 +64,9 @@ function parseDirectories(file, depth, targetDirectory) {
 }
 
 function buildMatrix(changedDirectories) {
-    include = [];
-    var directory;
-    for (directory of changedDirectories) {
+    let directories = [...new Set(changedDirectories)];
+    let include = []
+    for (directory of directories) {
         include.push({'directory': directory});
     }
     return {'include': include};