bug #23086 [FrameworkBundle] Fix perf issue in CacheClearCommand::war…

…mup() (nicolas-grekas)

This PR was merged into the 2.7 branch.

Discussion
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[FrameworkBundle] Fix perf issue in CacheClearCommand::warmup()

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | -
| License       | MIT
| Doc PR        | -

On slow file systems (eg on Windows), I noticed that writing files without doing any changes just kills perf.
Limiting the depth also helps when the symfony/cache component is used (because it can store thousands of files in its cache pool directory structure, and iterating there is also a waste of *fs* time).
I choose the max depth by looking at where existing apps put their files and added one level more just in case.

Commits
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b58f060 [FrameworkBundle] Fix perf issue in CacheClearCommand::warmup()

src/Symfony/Bundle/FrameworkBundle/Command/CacheClearCommand.php

@@ -141,7 +141,7 @@ protected function warmup($warmupDir, $realCacheDir, $enableOptionalWarmers = tr
         $safeTempKernel = str_replace('\\', '\\\\', get_class($tempKernel));
         $realKernelFQN = get_class($realKernel);
 
-        foreach (Finder::create()->files()->name('*.meta')->in($warmupDir) as $file) {
+        foreach (Finder::create()->files()->depth('<3')->name('*.meta')->in($warmupDir) as $file) {
             file_put_contents($file, preg_replace(
                 '/(C\:\d+\:)"'.$safeTempKernel.'"/',
                 sprintf('$1"%s"', $realKernelFQN),
@@ -153,14 +153,16 @@ protected function warmup($warmupDir, $realCacheDir, $enableOptionalWarmers = tr
         $search = array($warmupDir, str_replace('\\', '\\\\', $warmupDir));
         $replace = str_replace('\\', '/', $realCacheDir);
         foreach (Finder::create()->files()->in($warmupDir) as $file) {
-            $content = str_replace($search, $replace, file_get_contents($file));
-            file_put_contents($file, $content);
+            $content = str_replace($search, $replace, file_get_contents($file), $count);
+            if ($count) {
+                file_put_contents($file, $content);
+            }
         }
 
         // fix references to container's class
         $tempContainerClass = get_class($tempKernel->getContainer());
         $realContainerClass = get_class($realKernel->getContainer());
-        foreach (Finder::create()->files()->name($tempContainerClass.'*')->in($warmupDir) as $file) {
+        foreach (Finder::create()->files()->depth('<2')->name($tempContainerClass.'*')->in($warmupDir) as $file) {
             $content = str_replace($tempContainerClass, $realContainerClass, file_get_contents($file));
             file_put_contents($file, $content);
             rename($file, str_replace(DIRECTORY_SEPARATOR.$tempContainerClass, DIRECTORY_SEPARATOR.$realContainerClass, $file));