`ArrayIndexOutOfBoundsException` with the `FlutterColorProvider`

[AlexV525]

What happened

The exception was thrown when I was opening a project.

Version information

(SNAPSHOT indicates that I'm running with a local build on the main branch.)

IntelliJ IDEA 2025.2 • Flutter plugin io.flutter SNAPSHOT • Dart plugin 252.24322.5

Flutter 3.32.8 • channel stable • https://github.com/flutter/flutter.git
Framework • revision edada7c56e (5 weeks ago) • 2025-07-25 14:08:03 +0000
Engine • revision ef0cd00091 (5 weeks ago) • 2025-07-24 12:23:50 -0700
Tools • Dart 3.8.1 • DevTools 2.45.1

Exception

java.lang.ArrayIndexOutOfBoundsException: Index 915 out of bounds for length 915
	at com.intellij.util.text.CharArrayUtilKmp.getChars(CharArrayUtilKmp.kt:93)
	at com.intellij.util.text.CharArrayUtil.getChars(CharArrayUtil.java:50)
	at com.intellij.util.text.CharArrayUtil.getChars(CharArrayUtil.java:37)
	at com.intellij.psi.impl.source.tree.LeafElement.copyTo(LeafElement.java:74)
	at com.intellij.psi.impl.source.tree.AstBufferUtil$BufferVisitor.visitLeaf(AstBufferUtil.java:74)
	at com.intellij.psi.impl.source.tree.LeafElement.acceptTree(LeafElement.java:169)
	at com.intellij.psi.impl.source.tree.RecursiveTreeElementWalkingVisitor$1.visit(RecursiveTreeElementWalkingVisitor.java:66)
	at com.intellij.psi.impl.source.tree.RecursiveTreeElementWalkingVisitor$1.visit(RecursiveTreeElementWalkingVisitor.java:58)
	at com.intellij.util.WalkingState.walkChildren(WalkingState.java:63)
	at com.intellij.util.WalkingState.elementStarted(WalkingState.java:40)
	at com.intellij.psi.impl.source.tree.RecursiveTreeElementWalkingVisitor.visitNode(RecursiveTreeElementWalkingVisitor.java:85)
	at com.intellij.psi.impl.source.tree.RecursiveTreeElementWalkingVisitor.visitComposite(RecursiveTreeElementWalkingVisitor.java:80)
	at com.intellij.psi.impl.source.tree.AstBufferUtil$BufferVisitor.visitComposite(AstBufferUtil.java:96)
	at com.intellij.psi.impl.source.tree.CompositeElement.acceptTree(CompositeElement.java:115)
	at com.intellij.psi.impl.source.tree.AstBufferUtil.toBuffer(AstBufferUtil.java:22)
	at com.intellij.psi.impl.source.tree.AstBufferUtil.getTextSkippingWhitespaceComments(AstBufferUtil.java:29)
	at io.flutter.editor.FlutterColorProvider.parseColorElements(FlutterColorProvider.java:186)
	at io.flutter.editor.FlutterColorProvider.getColorFrom(FlutterColorProvider.java:76)
	at com.intellij.ui.ColorLineMarkerProvider.lambda$collectSlowLineMarkers$0(ColorLineMarkerProvider.java:49)
	at com.intellij.openapi.extensions.ExtensionPointName.computeSafeIfAny(ExtensionPointName.kt:86)
	at com.intellij.ui.ColorLineMarkerProvider.collectSlowLineMarkers(ColorLineMarkerProvider.java:48)
	at com.intellij.codeInsight.daemon.impl.LineMarkersPass.queryProviders(LineMarkersPass.java:227)
	at com.intellij.codeInsight.daemon.impl.LineMarkersPass.lambda$doCollectMarkers$2(LineMarkersPass.java:111)
	at com.intellij.codeInsight.daemon.impl.Divider.divideInsideAndOutsideInOneRoot(Divider.java:96)
	at com.intellij.codeInsight.daemon.impl.LineMarkersPass.doCollectMarkers(LineMarkersPass.java:107)
	at com.intellij.codeInsight.daemon.impl.LineMarkersPass.doCollectInformation(LineMarkersPass.java:79)
	at com.intellij.codeHighlighting.TextEditorHighlightingPass.collectInformation(TextEditorHighlightingPass.java:71)
	at com.intellij.codeInsight.daemon.impl.PassExecutorService$ScheduledPass.lambda$doRun$2(PassExecutorService.java:435)
	at com.intellij.platform.diagnostic.telemetry.helpers.TraceKt.use(trace.kt:29)
	at com.intellij.codeInsight.daemon.impl.PassExecutorService$ScheduledPass.lambda$doRun$3(PassExecutorService.java:431)
	at com.intellij.platform.locking.impl.NestedLocksThreadingSupport.tryRunReadAction(NestedLocksThreadingSupport.kt:826)
	at com.intellij.openapi.application.impl.ApplicationImpl.tryRunReadAction(ApplicationImpl.java:1221)
	at com.intellij.codeInsight.daemon.impl.PassExecutorService$ScheduledPass.lambda$doRun$4(PassExecutorService.java:421)
	at com.intellij.openapi.progress.impl.CoreProgressManager.lambda$executeProcessUnderProgress$14(CoreProgressManager.java:681)
	at com.intellij.openapi.progress.impl.CoreProgressManager.registerIndicatorAndRun(CoreProgressManager.java:756)
	at com.intellij.openapi.progress.impl.CoreProgressManager.computeUnderProgress(CoreProgressManager.java:712)
	at com.intellij.openapi.progress.impl.CoreProgressManager.executeProcessUnderProgress(CoreProgressManager.java:680)
	at com.intellij.openapi.progress.impl.ProgressManagerImpl.executeProcessUnderProgress(ProgressManagerImpl.java:78)
	at com.intellij.codeInsight.daemon.impl.PassExecutorService$ScheduledPass.doRun(PassExecutorService.java:420)
	at com.intellij.codeInsight.daemon.impl.PassExecutorService$ScheduledPass.lambda$run$0(PassExecutorService.java:395)
	at com.intellij.openapi.fileTypes.impl.FileTypeManagerImpl.cacheFileTypesInside(FileTypeManagerImpl.java:852)
	at com.intellij.codeInsight.daemon.impl.PassExecutorService$ScheduledPass.lambda$run$1(PassExecutorService.java:395)
	at com.intellij.openapi.application.impl.ApplicationImpl.executeByImpatientReader(ApplicationImpl.java:258)
	at com.intellij.codeInsight.daemon.impl.PassExecutorService$ScheduledPass.run(PassExecutorService.java:393)
	at com.intellij.concurrency.JobLauncherImpl$VoidForkJoinTask$1.exec(JobLauncherImpl.java:265)
	at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:507)
	at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1491)
	at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:2073)
	at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:2035)
	at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:187)

Flutter log

2025-08-30 14:54:50 io.flutter.run.daemon.DeviceDaemon [INFO   ] starting Flutter device daemon #1: flutter daemon  
2025-08-30 14:54:50 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, config, --machine]  
2025-08-30 14:54:50 io.flutter.jxbrowser.JxBrowserManager [INFO   ] card3-flutter: Installing JxBrowser  
2025-08-30 14:54:50 io.flutter.jxbrowser.JxBrowserManager [INFO   ] card3-flutter: JxBrowser platform files already exist, skipping download  
2025-08-30 14:54:50 io.flutter.jxbrowser.JxBrowserManager [INFO   ] Loaded JxBrowser files successfully  
2025-08-30 14:54:50 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, config, --machine]  
2025-08-30 14:54:50 io.flutter.FlutterInitializer [INFO   ] Executing Flutter plugin startup for project: project  
2025-08-30 14:54:50 io.flutter.FlutterInitializer [INFO   ] Flutter module has been found for project: project  
2025-08-30 14:54:50 io.flutter.sdk.FlutterSdk [INFO   ] flutter config --machine (406ms)  
2025-08-30 14:54:52 io.flutter.run.daemon.DeviceDaemon [INFO   ] flutter device daemon #1: Waiting for another flutter command to release the startup lock...  
2025-08-30 14:54:52 io.flutter.run.daemon.DeviceDaemon [INFO   ] flutter device daemon #1: A new version of Flutter is available!

To update to the latest version, run "flutter upgrade".  
2025-08-30 14:54:52 io.flutter.run.daemon.DeviceDaemon [INFO   ] flutter device daemon #1: Device daemon started.  
2025-08-30 14:54:52 io.flutter.sdk.FlutterSdk [INFO   ] flutter config --machine (2362ms)  
2025-08-30 14:55:12 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, pub, get]  
2025-08-30 14:56:00 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, pub, get]  
2025-08-30 14:57:06 io.flutter.run.daemon.DevToolsServerTask [INFO   ] Finding or starting DevTools  
2025-08-30 14:58:08 io.flutter.run.daemon.FlutterAppDaemonEventListener [WARNING] Failed request ConnectedApp.registerVmServiceto DTD with params: {"uri":"ws://127.0.0.1:62088/_g2-m4xOGOc=/ws","name":"dd61d003-a0e3-4ebc-b97e-b6bf000c9a0e"}  
2025-08-30 14:58:08 io.flutter.run.daemon.FlutterAppDaemonEventListener [WARNING] Result: null  
2025-08-30 17:53:23 io.flutter.run.daemon.FlutterAppDaemonEventListener [INFO   ] app shutdown took longer than 100ms  
2025-08-30 17:54:15 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, pub, get]  
2025-08-30 17:54:47 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, pub, get]  
2025-08-30 17:54:55 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, pub, get]  
2025-08-30 18:05:07 io.flutter.sdk.FlutterCommand [INFO   ] flutter [--no-color, config, --machine]  
2025-08-30 18:05:07 io.flutter.FlutterInitializer [INFO   ] Executing Flutter plugin startup for project: new_project  
2025-08-30 18:05:07 io.flutter.FlutterInitializer [INFO   ] Flutter module has been found for project: new_project  
2025-08-30 18:05:07 io.flutter.sdk.FlutterSdk [INFO   ] flutter config --machine (691ms)  
2025-08-30 18:05:08 io.flutter.run.daemon.DeviceDaemon [INFO   ] starting Flutter device daemon #2: flutter daemon  
2025-08-30 18:05:09 io.flutter.run.daemon.DeviceDaemon [INFO   ] flutter device daemon #2: Device daemon started.  

[helin24]

I'm not able to reproduce - is this in a small project you can share? Or is it any project?

[AlexV525]

I'm not able to reproduce - is this in a small project you can share? Or is it any project?

It only happened once last week. It doesn't seem to occur in a high frequency. I guess it's random based on file caches/index probably.

[helin24]

Ah okay, if it's intermittent I'm wondering if logging could help us in the future (if you can't tell, I've been working on logging. So it is occurring to me all over the place). I don't understand this code well enough to suggest what information might help here, but I'll mark this as a good first issue (at least, adding some informational logs) for now.