Stop re-running tests when mtime has not changed

CHANGELOG.md

@@ -71,6 +71,7 @@
 - `[expect]` Fix toMatchObject matcher when used with `Object.create(null)` ([#7334](https://github.com/facebook/jest/pull/7334))
 - `[jest-haste-map]` [**BREAKING**] Recover files correctly after haste name collisions are fixed ([#7329](https://github.com/facebook/jest/pull/7329))
 - `[jest-haste-map]` Remove legacy condition for duplicate module detection ([#7333](https://github.com/facebook/jest/pull/7333))
+- `[jest-haste-map]` Stop reporting files as changed when they are only accessed ([#7347](https://github.com/facebook/jest/pull/7347))
 
 ### Chore & Maintenance
 

packages/jest-haste-map/src/index.js

@@ -800,6 +800,19 @@ class HasteMap extends EventEmitter {
         return;
       }
 
+      const relativeFilePath = fastPath.relative(rootDir, filePath);
+      const fileMetadata = hasteMap.files.get(relativeFilePath);
+
+      // The file has been accessed, not modified
+      if (
+        fileMetadata &&
+        type === 'change' &&
+        stat &&
+        fileMetadata[H.MTIME] === stat.mtime.getTime()
+      ) {
+        return;
+      }
+
       changeQueue = changeQueue
         .then(() => {
           // If we get duplicate events for the same file, ignore them.
@@ -830,9 +843,6 @@ class HasteMap extends EventEmitter {
 
           const add = () => eventsQueue.push({filePath, stat, type});
 
-          const relativeFilePath = fastPath.relative(rootDir, filePath);
-          const fileMetadata = hasteMap.files.get(relativeFilePath);
-
           // If it's not an addition, delete the file and all its metadata
           if (fileMetadata != null) {
             const moduleName = fileMetadata[H.ID];