Preserve file data when sha1s match

jestjs · Sep 17, 2018 · 38c79fa · 38c79fa
1 parent 9822231
commit 38c79fa
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Showing 2 changed files with 31 additions and 14 deletions.
diff --git a/packages/jest-haste-map/src/crawlers/__tests__/watchman.test.js b/packages/jest-haste-map/src/crawlers/__tests__/watchman.test.js
@@ -223,6 +223,8 @@ describe('watchman watch', () => {
   });
 
   test('resets the file object when watchman is restarted', () => {
+    const mockTomatoSha1 = '321f6b7e8bf7f29aab89c5e41a555b1b0baa41a9';
+
     mockResponse = {
       'list-capabilities': {
         [undefined]: {
@@ -245,8 +247,9 @@ describe('watchman watch', () => {
             },
             {
               exists: true,
-              mtime_ms: {toNumber: () => 31},
+              mtime_ms: {toNumber: () => 76},
               name: 'fruits/tomato.js',
+              'content.sha1hex': mockTomatoSha1,
             },
           ],
           is_fresh_instance: true,
@@ -256,8 +259,10 @@ describe('watchman watch', () => {
       'watch-project': WATCH_PROJECT_MOCK,
     };
 
-    const mockMetadata = ['Banana', 41, 1, ['Raspberry'], null];
-    mockFiles.set(BANANA, mockMetadata);
+    const mockBananaMetadata = ['Banana', 41, 1, ['Raspberry'], null];
+    mockFiles.set(BANANA, mockBananaMetadata);
+    const mockTomatoMetadata = ['Tomato', 31, 1, [], mockTomatoSha1];
+    mockFiles.set(TOMATO, mockTomatoMetadata);
 
     const clocks = createMap({
       [ROOT_MOCK]: 'c:fake-clock:1',
@@ -284,17 +289,18 @@ describe('watchman watch', () => {
       // /fruits/strawberry.js was removed from the file list.
       expect(data.files).toEqual(
         createMap({
-          [BANANA]: mockMetadata,
+          [BANANA]: mockBananaMetadata,
           [KIWI]: ['', 42, 0, [], null],
-          [TOMATO]: mockFiles.get(TOMATO),
+          [TOMATO]: ['Tomato', 76, 1, [], mockTomatoSha1],
         }),
       );
 
       // Even though the file list was reset, old file objects are still reused
-      // if no changes have been made.
-      expect(data.files.get(BANANA)).toBe(mockMetadata);
+      // if no changes have been made
+      expect(data.files.get(BANANA)).toBe(mockBananaMetadata);
 
-      expect(data.files.get(TOMATO)).toBe(mockFiles.get(TOMATO));
+      // Old file objects are not reused if they have a different mtime
+      expect(data.files.get(TOMATO)).not.toBe(mockTomatoMetadata);
     });
   });
 

diff --git a/packages/jest-haste-map/src/crawlers/watchman.js b/packages/jest-haste-map/src/crawlers/watchman.js
@@ -169,16 +169,27 @@ module.exports = async function watchmanCrawl(
           typeof fileData.mtime_ms === 'number'
             ? fileData.mtime_ms
             : fileData.mtime_ms.toNumber();
+        let sha1hex = fileData['content.sha1hex'];
+        if (typeof sha1hex !== 'string' || sha1hex.length !== 40) {
+          sha1hex = null;
+        }
+
         const existingFileData = data.files.get(name);
         if (existingFileData && existingFileData[H.MTIME] === mtime) {
           files.set(name, existingFileData);
+        } else if (
+          existingFileData &&
+          sha1hex &&
+          existingFileData[H.SHA1] === sha1hex
+        ) {
+          files.set(name, [
+            existingFileData[0],
+            mtime,
+            existingFileData[2],
+            existingFileData[3],
+            existingFileData[4],
+          ]);
         } else {
-          let sha1hex = fileData['content.sha1hex'];
-
-          if (typeof sha1hex !== 'string' || sha1hex.length !== 40) {
-            sha1hex = null;
-          }
-
           // See ../constants.js
           files.set(name, ['', mtime, 0, [], sha1hex]);
         }