548003 – Content assist inside of specific lambdas results in NullPointerException

Bug 548003 - Content assist inside of specific lambdas results in NullPointerException

Summary: Content assist inside of specific lambdas results in NullPointerException

Status:	NEW

Alias:	None

Product:	JDT
Classification:	Eclipse Project
Component:	Core (show other bugs)
Version:	4.11
Hardware:	All All

Importance:	P3 normal (vote)
Target Milestone:	---
Assignee:	JDT-Core-Inbox
QA Contact:

URL:
Whiteboard:	stalebug
Keywords:

Depends on:
Blocks:

Reported:	2019-06-06 09:16 EDT by Markus Gaisbauer
Modified:	2023-05-25 16:39 EDT (History)
CC List:	1 user (show)

See Also:

Attachments
Java class which reproduces the problem (1.74 KB, application/octet-stream) 2019-06-06 09:16 EDT, Markus Gaisbauer	no flags	Details
View All Add an attachment (proposed patch, testcase, etc.)

Note You need to log in before you can comment on or make changes to this bug.

Description Markus Gaisbauer

2019-06-06 09:16:26 EDT

Created attachment 278837 [details]
Java class which reproduces the problem

We heavily use nested lambdas in our code base and I ran into problems with content assist. Either it does not show any proposals or it shows a popup "Problems During Content Assist".

The following reproduces the problem in Eclipse 2019.03:

    static class X {
        public X child(Consumer<X> c) {
            return this;
        }
    }

    void bad(X x) {
        new Runnable() {
            @Override
            public void run() {
                x.child(_1 -> _1
                    .child(_2 -> _2 // . CTRL-SPACE does not work here
                        .child(_3 -> {})
                    )
                );
            }
        };
        
        new Runnable() {
            @Override
            public void run() {
                x.child(_1 -> _1
                    .child(_2 -> _2 // . CTRL-SPACE results in NullPointerException and popup
                        .child(new Consumer<X>() {
                            @Override
                            public void accept(X x) {

                            }
                        })
                    )
                );
            }
        };
    }

I get the following exception stacktrace in the log:

    !ENTRY org.eclipse.jdt.ui 2 0 2019-06-06 14:38:43.891
    !MESSAGE The 'org.eclipse.jdt.ui.JavaAllCompletionProposalComputer' proposal computer from the 'org.eclipse.jdt.ui' plug-in did not complete normally. The extension has thrown a runtime exception.
    !STACK 0
    java.lang.NullPointerException
        at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.getAnonymousConstructorBinding(QualifiedAllocationExpression.java:659)
        at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveTypeForQualifiedAllocationExpression(QualifiedAllocationExpression.java:553)
        at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveType(QualifiedAllocationExpression.java:303)
        at org.eclipse.jdt.internal.compiler.ast.MessageSend.resolveType(MessageSend.java:730)
        at org.eclipse.jdt.internal.compiler.ast.ReturnStatement.resolve(ReturnStatement.java:333)
        at org.eclipse.jdt.internal.compiler.ast.LambdaExpression.resolveType(LambdaExpression.java:453)
        at org.eclipse.jdt.internal.compiler.ast.ASTNode.resolvePolyExpressionArguments(ASTNode.java:705)
        at org.eclipse.jdt.internal.compiler.ast.MessageSend.findMethodBinding(MessageSend.java:961)
        at org.eclipse.jdt.internal.compiler.ast.MessageSend.resolveType(MessageSend.java:775)
        at org.eclipse.jdt.internal.compiler.ast.Expression.resolve(Expression.java:1034)
        at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolveStatements(AbstractMethodDeclaration.java:641)
        at org.eclipse.jdt.internal.compiler.ast.MethodDeclaration.resolveStatements(MethodDeclaration.java:316)
        at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolve(AbstractMethodDeclaration.java:551)
        at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1229)
        at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1329)
        at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.getAnonymousConstructorBinding(QualifiedAllocationExpression.java:662)
        at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveTypeForQualifiedAllocationExpression(QualifiedAllocationExpression.java:553)
        at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveType(QualifiedAllocationExpression.java:303)
        at org.eclipse.jdt.internal.compiler.ast.Expression.resolve(Expression.java:1034)
        at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolveStatements(AbstractMethodDeclaration.java:641)
        at org.eclipse.jdt.internal.compiler.ast.MethodDeclaration.resolveStatements(MethodDeclaration.java:316)
        at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolve(AbstractMethodDeclaration.java:551)
        at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1229)
        at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1354)
        at org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration.resolve(CompilationUnitDeclaration.java:652)
        at org.eclipse.jdt.internal.codeassist.CompletionEngine.complete(CompletionEngine.java:2250)
        at org.eclipse.jdt.internal.core.Openable.codeComplete(Openable.java:136)
        at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:368)
        at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:358)
        at org.eclipse.jdt.internal.ui.text.java.JavaCompletionProposalComputer.internalComputeCompletionProposals(JavaCompletionProposalComputer.java:253)
        at org.eclipse.jdt.internal.ui.text.java.JavaCompletionProposalComputer.computeCompletionProposals(JavaCompletionProposalComputer.java:215)
        at org.eclipse.jdt.internal.ui.text.java.JavaTypeCompletionProposalComputer.computeCompletionProposals(JavaTypeCompletionProposalComputer.java:66)
        at org.eclipse.jdt.internal.ui.text.java.CompletionProposalComputerDescriptor.computeCompletionProposals(CompletionProposalComputerDescriptor.java:336)
        at org.eclipse.jdt.internal.ui.text.java.CompletionProposalCategory.computeCompletionProposals(CompletionProposalCategory.java:340)
        at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.collectProposals(ContentAssistProcessor.java:334)
        at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.computeCompletionProposals(ContentAssistProcessor.java:291)
        at org.eclipse.jface.text.contentassist.ContentAssistant$2.lambda$0(ContentAssistant.java:2014)
        at java.util.Collections$SingletonSet.forEach(Collections.java:4767)
        at org.eclipse.jface.text.contentassist.ContentAssistant$2.run(ContentAssistant.java:2013)
        at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
        at org.eclipse.jface.text.contentassist.ContentAssistant.computeCompletionProposals(ContentAssistant.java:2010)
        at org.eclipse.jface.text.contentassist.CompletionProposalPopup.computeProposals(CompletionProposalPopup.java:573)
        at org.eclipse.jface.text.contentassist.CompletionProposalPopup.lambda$0(CompletionProposalPopup.java:503)
        at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:72)
        at org.eclipse.jface.text.contentassist.CompletionProposalPopup.showProposals(CompletionProposalPopup.java:498)
        at org.eclipse.jface.text.contentassist.ContentAssistant$AutoAssistListener.lambda$0(ContentAssistant.java:380)
        at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:40)
        at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:185)
        at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:3919)
        at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3550)
        at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$5.run(PartRenderingEngine.java:1173)
        at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
        at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1062)
        at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
        at org.eclipse.ui.internal.Workbench.lambda$3(Workbench.java:636)
        at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:339)
        at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:563)
        at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:151)
        at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:155)
        at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:203)
        at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:137)
        at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:107)
        at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:400)
        at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:255)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:659)
        at org.eclipse.equinox.launcher.Main.basicRun(Main.java:595)
        at org.eclipse.equinox.launcher.Main.run(Main.java:1501)

The following are small variations of the code above where content assist works as expected:

    void good(X x) {
        new Runnable() {
            @Override
            public void run() {
                x.child(_1 -> _1
                    .child(_2 -> _2 // . CTRL-SPACE works here
                        .child(_3 -> _3.hashCode())
                    )
                );
            }
        };

        Runnable r = () -> {
            x.child(_1 -> _1
                .child(_2 -> _2// . CTRL-SPACE works here
                    .child(_3 -> {})
                )
            );
        };

        new Runnable() {
            @Override
            public void run() {
                x.child(new Consumer<X>() {
                    @Override
                    public void accept(X x) {
                        x.child(_2 -> _2 // . CTRL-SPACE works here
                            .child(_3 -> {})
                        );
                    }
                });
            }
        };

    }

Comment 1 Andrey Loskutov

2019-06-06 09:46:21 EDT

I can't reproduce your NPE with Eclipse 4.12 RC1. 

I've tried to invoke content assist on lines with comments placing cursor after the "dot".

However I see CCE errors while code completion inside "void" keyword and full UI hangup (100% CPU load) on line 30 on completion inside "accept" name, both coming from e4 tools proposal computer.

Comment 2 Andrey Loskutov

2019-06-06 10:07:01 EDT

(In reply to Andrey Loskutov from comment #1)
> I can't reproduce your NPE with Eclipse 4.12 RC1. 
> 
> I've tried to invoke content assist on lines with comments placing cursor
> after the "dot".
> 
> However I see CCE errors while code completion inside "void" keyword and
> full UI hangup (100% CPU load) on line 30 on completion inside "accept"
> name, both coming from e4 tools proposal computer.

Here are the stacks (I had to kill IDE):

The "regular" error:

java.lang.ClassCastException: class org.eclipse.jdt.internal.compiler.ast.TypeDeclaration cannot be cast to class org.eclipse.jdt.internal.compiler.ast.AbstractVariableDeclaration (org.eclipse.jdt.internal.compiler.ast.TypeDeclaration and org.eclipse.jdt.internal.compiler.ast.AbstractVariableDeclaration are in unnamed module of loader org.eclipse.osgi.internal.loader.EquinoxClassLoader @4b9dc62f)
	at org.eclipse.jdt.internal.compiler.parser.Parser.consumeExitVariableWithoutInitialization(Parser.java:4026)
	at org.eclipse.jdt.internal.codeassist.complete.CompletionParser.consumeExitVariableWithoutInitialization(CompletionParser.java:2833)
	at org.eclipse.jdt.internal.compiler.parser.Parser.consumeRule(Parser.java:6850)
	at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:11999)
	at org.eclipse.jdt.internal.codeassist.impl.AssistParser.parseBlockStatements(AssistParser.java:2029)
	at org.eclipse.jdt.internal.codeassist.impl.AssistParser.parseBlockStatements(AssistParser.java:1869)
	at org.eclipse.jdt.internal.codeassist.impl.Engine.parseBlockStatements(Engine.java:349)
	at org.eclipse.jdt.internal.codeassist.impl.Engine.parseBlockStatements(Engine.java:312)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.complete(CompletionEngine.java:2250)
	at org.eclipse.jdt.internal.core.Openable.codeComplete(Openable.java:136)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:368)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:363)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:353)
	at org.eclipse.jdt.ui.text.java.JavaContentAssistInvocationContext.computeKeywordsAndContext(JavaContentAssistInvocationContext.java:301)
	at org.eclipse.jdt.ui.text.java.JavaContentAssistInvocationContext.getCoreContext(JavaContentAssistInvocationContext.java:177)
	at org.eclipse.e4.internal.tools.jdt.templates.E4TemplateCompletionProposalComputer.computeCompletionEngine(E4TemplateCompletionProposalComputer.java:166)
	at org.eclipse.jdt.internal.ui.text.java.AbstractTemplateCompletionProposalComputer.computeCompletionProposals(AbstractTemplateCompletionProposalComputer.java:65)
	at org.eclipse.jdt.internal.ui.text.java.CompletionProposalComputerDescriptor.computeCompletionProposals(CompletionProposalComputerDescriptor.java:336)
	at org.eclipse.jdt.internal.ui.text.java.CompletionProposalCategory.computeCompletionProposals(CompletionProposalCategory.java:340)
	at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.collectProposals(ContentAssistProcessor.java:334)
	at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.computeCompletionProposals(ContentAssistProcessor.java:291)
	at org.eclipse.jface.text.contentassist.ContentAssistant$2.lambda$0(ContentAssistant.java:2014)


The endless loop case:

Stack Trace
	at org.eclipse.jdt.internal.compiler.parser.Scanner.<init>(Scanner.java:202)
	at org.eclipse.jdt.internal.compiler.parser.Scanner.<init>(Scanner.java:303)
	at org.eclipse.jdt.internal.codeassist.complete.CompletionScanner.<init>(CompletionScanner.java:56)
	at org.eclipse.jdt.internal.codeassist.complete.CompletionParser.initializeScanner(CompletionParser.java:5203)
	at org.eclipse.jdt.internal.compiler.parser.Parser.<init>(Parser.java:963)
	at org.eclipse.jdt.internal.codeassist.impl.AssistParser.<init>(AssistParser.java:134)
	at org.eclipse.jdt.internal.codeassist.complete.CompletionParser.<init>(CompletionParser.java:190)
	at org.eclipse.jdt.internal.codeassist.complete.CompletionParser.createSnapShotParser(CompletionParser.java:5544)
	at org.eclipse.jdt.internal.codeassist.complete.CompletionParser.updateRecoveryState(CompletionParser.java:5701)
	at org.eclipse.jdt.internal.compiler.parser.Parser.resumeOnSyntaxError(Parser.java:13325)
	at org.eclipse.jdt.internal.codeassist.complete.CompletionParser.resumeOnSyntaxError(CompletionParser.java:5585)
	at org.eclipse.jdt.internal.compiler.parser.Parser.parse(Parser.java:11905)
	at org.eclipse.jdt.internal.codeassist.impl.AssistParser.parseBlockStatements(AssistParser.java:2029)
	at org.eclipse.jdt.internal.codeassist.impl.AssistParser.parseBlockStatements(AssistParser.java:1869)
	at org.eclipse.jdt.internal.codeassist.impl.Engine.parseBlockStatements(Engine.java:349)
	at org.eclipse.jdt.internal.codeassist.impl.Engine.parseBlockStatements(Engine.java:312)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.complete(CompletionEngine.java:2250)
	at org.eclipse.jdt.internal.core.Openable.codeComplete(Openable.java:136)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:368)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:363)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:353)
	at org.eclipse.jdt.ui.text.java.JavaContentAssistInvocationContext.computeKeywordsAndContext(JavaContentAssistInvocationContext.java:301)
	at org.eclipse.jdt.ui.text.java.JavaContentAssistInvocationContext.getCoreContext(JavaContentAssistInvocationContext.java:177)
	at org.eclipse.e4.internal.tools.jdt.templates.E4TemplateCompletionProposalComputer.computeCompletionEngine(E4TemplateCompletionProposalComputer.java:166)
	at org.eclipse.jdt.internal.ui.text.java.AbstractTemplateCompletionProposalComputer.computeCompletionProposals(AbstractTemplateCompletionProposalComputer.java:65)
	at org.eclipse.jdt.internal.ui.text.java.CompletionProposalComputerDescriptor.computeCompletionProposals(CompletionProposalComputerDescriptor.java:336)
	at org.eclipse.jdt.internal.ui.text.java.CompletionProposalCategory.computeCompletionProposals(CompletionProposalCategory.java:340)
	at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.collectProposals(ContentAssistProcessor.java:334)
	at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.computeCompletionProposals(ContentAssistProcessor.java:291)
	at org.eclipse.jface.text.contentassist.ContentAssistant$2.lambda$0(ContentAssistant.java:2014)
	at org.eclipse.jface.text.contentassist.ContentAssistant$2$$Lambda$1350/0x0000000841253440.accept(Unknown Source)
	at java.base@11.0.2/java.util.Collections$SingletonSet.forEach(Collections.java:4795)
	at org.eclipse.jface.text.contentassist.ContentAssistant$2.run(ContentAssistant.java:2013)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
	at org.eclipse.jface.text.contentassist.ContentAssistant.computeCompletionProposals(ContentAssistant.java:2010)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.computeProposals(CompletionProposalPopup.java:575)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.lambda$0(CompletionProposalPopup.java:505)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup$$Lambda$1349/0x0000000841253c40.run(Unknown Source)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:72)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.showProposals(CompletionProposalPopup.java:500)
	at org.eclipse.jface.text.contentassist.ContentAssistant.showPossibleCompletions(ContentAssistant.java:1824)
	at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitEditor$AdaptedSourceViewer.doOperation(CompilationUnitEditor.java:189)
	at org.eclipse.ui.texteditor.ContentAssistAction.lambda$0(ContentAssistAction.java:85)
	at org.eclipse.ui.texteditor.ContentAssistAction$$Lambda$1490/0x00000008405acc40.run(Unknown Source)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:72)
	at org.eclipse.ui.texteditor.ContentAssistAction.run(ContentAssistAction.java:84)

Comment 3 Markus Gaisbauer

2019-06-06 10:09:03 EDT

To clarify. In all of the samples I added a "dot" directly after "_2 -> _2" like "_2 -> _2." and then hit Ctrl-Space.

Comment 4 Markus Gaisbauer

2019-06-06 10:12:28 EDT

While content assist is invoked, the whole expression is invalid (two "dot" tokens in a row).

Comment 5 Andrey Loskutov

2019-06-06 10:13:25 EDT

(In reply to Markus Gaisbauer from comment #3)
> To clarify. In all of the samples I added a "dot" directly after "_2 -> _2"
> like "_2 -> _2." and then hit Ctrl-Space.

OK, thanks, I can reproduce this now. I've also disabled e4 proposals, still same problem, here the fresh stack from 4.12 RC2:

eclipse.buildId=4.12.0.I20190605-1800
java.version=11.0.2
java.vendor=Oracle Corporation
BootLoader constants: OS=linux, ARCH=x86_64, WS=gtk, NL=en_US
Command-line arguments:  -os linux -ws gtk -arch x86_64

org.eclipse.jdt.ui
Warning
Thu Jun 06 16:11:14 CEST 2019
The 'org.eclipse.jdt.ui.JavaAllCompletionProposalComputer' proposal computer from the 'org.eclipse.jdt.ui' plug-in did not complete normally. The extension has thrown a runtime exception.

java.lang.NullPointerException
	at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.getAnonymousConstructorBinding(QualifiedAllocationExpression.java:659)
	at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveTypeForQualifiedAllocationExpression(QualifiedAllocationExpression.java:553)
	at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveType(QualifiedAllocationExpression.java:303)
	at org.eclipse.jdt.internal.compiler.ast.MessageSend.resolveType(MessageSend.java:729)
	at org.eclipse.jdt.internal.compiler.ast.ReturnStatement.resolve(ReturnStatement.java:310)
	at org.eclipse.jdt.internal.compiler.ast.LambdaExpression.resolveType(LambdaExpression.java:453)
	at org.eclipse.jdt.internal.compiler.ast.ASTNode.resolvePolyExpressionArguments(ASTNode.java:708)
	at org.eclipse.jdt.internal.compiler.ast.MessageSend.findMethodBinding(MessageSend.java:960)
	at org.eclipse.jdt.internal.compiler.ast.MessageSend.resolveType(MessageSend.java:774)
	at org.eclipse.jdt.internal.compiler.ast.Expression.resolve(Expression.java:1066)
	at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolveStatements(AbstractMethodDeclaration.java:641)
	at org.eclipse.jdt.internal.compiler.ast.MethodDeclaration.resolveStatements(MethodDeclaration.java:316)
	at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolve(AbstractMethodDeclaration.java:551)
	at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1280)
	at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1380)
	at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.getAnonymousConstructorBinding(QualifiedAllocationExpression.java:662)
	at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveTypeForQualifiedAllocationExpression(QualifiedAllocationExpression.java:553)
	at org.eclipse.jdt.internal.compiler.ast.QualifiedAllocationExpression.resolveType(QualifiedAllocationExpression.java:303)
	at org.eclipse.jdt.internal.compiler.ast.Expression.resolve(Expression.java:1066)
	at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolveStatements(AbstractMethodDeclaration.java:641)
	at org.eclipse.jdt.internal.compiler.ast.MethodDeclaration.resolveStatements(MethodDeclaration.java:316)
	at org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration.resolve(AbstractMethodDeclaration.java:551)
	at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1280)
	at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.resolve(TypeDeclaration.java:1405)
	at org.eclipse.jdt.internal.compiler.ast.CompilationUnitDeclaration.resolve(CompilationUnitDeclaration.java:652)
	at org.eclipse.jdt.internal.codeassist.CompletionEngine.complete(CompletionEngine.java:2255)
	at org.eclipse.jdt.internal.core.Openable.codeComplete(Openable.java:136)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:368)
	at org.eclipse.jdt.internal.core.CompilationUnit.codeComplete(CompilationUnit.java:358)
	at org.eclipse.jdt.internal.ui.text.java.JavaCompletionProposalComputer.internalComputeCompletionProposals(JavaCompletionProposalComputer.java:253)
	at org.eclipse.jdt.internal.ui.text.java.JavaCompletionProposalComputer.computeCompletionProposals(JavaCompletionProposalComputer.java:215)
	at org.eclipse.jdt.internal.ui.text.java.JavaTypeCompletionProposalComputer.computeCompletionProposals(JavaTypeCompletionProposalComputer.java:66)
	at org.eclipse.jdt.internal.ui.text.java.CompletionProposalComputerDescriptor.computeCompletionProposals(CompletionProposalComputerDescriptor.java:336)
	at org.eclipse.jdt.internal.ui.text.java.CompletionProposalCategory.computeCompletionProposals(CompletionProposalCategory.java:340)
	at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.collectProposals(ContentAssistProcessor.java:334)
	at org.eclipse.jdt.internal.ui.text.java.ContentAssistProcessor.computeCompletionProposals(ContentAssistProcessor.java:291)
	at org.eclipse.jface.text.contentassist.ContentAssistant$2.lambda$0(ContentAssistant.java:2014)
	at java.base/java.util.Collections$SingletonSet.forEach(Collections.java:4795)
	at org.eclipse.jface.text.contentassist.ContentAssistant$2.run(ContentAssistant.java:2013)
	at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:45)
	at org.eclipse.jface.text.contentassist.ContentAssistant.computeCompletionProposals(ContentAssistant.java:2010)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.computeProposals(CompletionProposalPopup.java:575)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.lambda$0(CompletionProposalPopup.java:505)
	at org.eclipse.swt.custom.BusyIndicator.showWhile(BusyIndicator.java:72)
	at org.eclipse.jface.text.contentassist.CompletionProposalPopup.showProposals(CompletionProposalPopup.java:500)
	at org.eclipse.jface.text.contentassist.ContentAssistant.showPossibleCompletions(ContentAssistant.java:1824)
	at org.eclipse.jdt.internal.ui.javaeditor.CompilationUnitEditor$AdaptedSourceViewer.doOperation(CompilationUnitEditor.java:189)
	at org.eclipse.ui.texteditor.ContentAssistAction.lambda$0(ContentAssistAction.java:85)

Comment 6 Andrey Loskutov

2019-06-06 10:14:34 EDT

(In reply to Markus Gaisbauer from comment #4)
> While content assist is invoked, the whole expression is invalid (two "dot"
> tokens in a row).

No need in second dot, just hit Ctrl+Space with cursor right after "_2" and you will see the error.

Comment 7 Markus Gaisbauer

2019-06-06 10:21:24 EDT

Correct. But without the dot I would not hit Ctrl-Space because I already know that the proposal list is empty :) E.g. also directly after "_1 -> _1".

Comment 8 Eclipse Genie

2021-05-27 05:59:16 EDT

This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet.

If you have further information on the current state of the bug, please add it. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant.

--
The automated Eclipse Genie.

Comment 9 Eclipse Genie

2023-05-25 16:39:45 EDT

This bug hasn't had any activity in quite some time. Maybe the problem got resolved, was a duplicate of something else, or became less pressing for some reason - or maybe it's still relevant but just hasn't been looked at yet.

If you have further information on the current state of the bug, please add it. The information can be, for example, that the problem still occurs, that you still want the feature, that more information is needed, or that the bug is (for whatever reason) no longer relevant.

--
The automated Eclipse Genie.