Tweak jest-haste-map watchman initial query to make it faster

CHANGELOG.md

@@ -4,6 +4,10 @@
 
 - `[jest-cli]` Watch plugins now have access to a broader range of global configuration options in their `updateConfigAndRun` callbacks, so they can provide a wider set of extra features ([#6473](https://github.com/facebook/jest/pull/6473))
 
+## Fixes
+
+- `[jest-haste-map]` Optimize watchman crawler by using `glob` on initial query ([#6689](https://github.com/facebook/jest/pull/6689))
+
 ## 23.4.0
 
 ### Features

packages/jest-haste-map/src/crawlers/__tests__/watchman.test.js

@@ -141,7 +141,12 @@ describe('watchman watch', () => {
 
       expect(query[2].fields).toEqual(['name', 'exists', 'mtime_ms']);
 
-      expect(query[2].suffix).toEqual(['js', 'json']);
+      expect(query[2].glob).toEqual([
+        'fruits/**/*.js',
+        'fruits/**/*.json',
+        'vegetables/**/*.js',
+        'vegetables/**/*.json',
+      ]);
 
       expect(data.clocks).toEqual({
         [ROOT_MOCK]: 'c:fake-clock:1',
@@ -412,7 +417,7 @@ describe('watchman watch', () => {
 
       expect(query[2].fields).toEqual(['name', 'exists', 'mtime_ms']);
 
-      expect(query[2].suffix).toEqual(['js', 'json']);
+      expect(query[2].glob).toEqual(['**/*.js', '**/*.json']);
 
       expect(data.clocks).toEqual({
         [ROOT_MOCK]: 'c:fake-clock:1',

packages/jest-haste-map/src/crawlers/watchman.js

@@ -93,18 +93,30 @@ module.exports = async function watchmanCrawl(
       Array.from(rootProjectDirMappings).map(
         async ([root, directoryFilters]) => {
           const expression = Array.from(defaultWatchExpression);
+          const glob = [];
+
           if (directoryFilters.length > 0) {
             expression.push([
               'anyof',
               ...directoryFilters.map(dir => ['dirname', dir]),
             ]);
+
+            for (const directory of directoryFilters) {
+              for (const extension of extensions) {
+                glob.push(`${directory}/**/*.${extension}`);
+              }
+            }
+          } else {
+            for (const extension of extensions) {
+              glob.push(`**/*.${extension}`);
+            }
           }
 
           const query = clocks[root]
             ? // Use the `since` generator if we have a clock available
               {expression, fields, since: clocks[root]}
-            : // Otherwise use the `suffix` generator
-              {expression, fields, suffix: extensions};
+            : // Otherwise use the `glob` filter
+              {expression, fields, glob};
 
           const response = await cmd('query', root, query);