I get an AST compiler error when trying to use gwt-beans-validator (which includes gwt-time 2.0.10) with GWT 2.10.0

[dnouls]

I have a large project where I am trying to migrate to GWT 2.10.0. We are depending on gwt-beans-validator, which is now depending on gwt-time 2.0.10.

For some reason I cannot even compile a simple utility library and run the GWTTestCases there.
When trying to run the GWTTestCase I get the following compiler exception:

[ERROR] Compiler aborted with an exception 
com.google.gwt.dev.jjs.InternalCompilerException: Error constructing Java AST
	at com.google.gwt.dev.jjs.impl.GwtAstBuilder.translateException(GwtAstBuilder.java:4033)
	at com.google.gwt.dev.jjs.impl.GwtAstBuilder$AstVisitor.endVisit(GwtAstBuilder.java:647)
	at org.eclipse.jdt.internal.compiler.ast.ConditionalExpression.traverse(ConditionalExpression.java:827)
	at org.eclipse.jdt.internal.compiler.ast.BinaryExpression.traverse(BinaryExpression.java:1920)
	at org.eclipse.jdt.internal.compiler.ast.BinaryExpression.traverse(BinaryExpression.java:1919)
	at org.eclipse.jdt.internal.compiler.ast.BinaryExpression.traverse(BinaryExpression.java:1919)
	at org.eclipse.jdt.internal.compiler.ast.BinaryExpression.traverse(BinaryExpression.java:1919)
	at org.eclipse.jdt.internal.compiler.ast.CombinedBinaryExpression.traverse(CombinedBinaryExpression.java:370)
	at org.eclipse.jdt.internal.compiler.ast.ReturnStatement.traverse(ReturnStatement.java:402)
	at org.eclipse.jdt.internal.compiler.ast.MethodDeclaration.traverse(MethodDeclaration.java:365)
	at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.traverse(TypeDeclaration.java:1560)
	at org.eclipse.jdt.internal.compiler.ast.TypeDeclaration.traverse(TypeDeclaration.java:1432)
	at com.google.gwt.dev.jjs.impl.GwtAstBuilder.processImpl(GwtAstBuilder.java:3969)
	at com.google.gwt.dev.jjs.impl.GwtAstBuilder.process(GwtAstBuilder.java:4007)
	at com.google.gwt.dev.javac.CompilationStateBuilder$CompileMoreLater$UnitProcessorImpl.process(CompilationStateBuilder.java:128)
	at com.google.gwt.dev.javac.JdtCompiler$CompilerImpl.process(JdtCompiler.java:322)
	at org.eclipse.jdt.internal.compiler.Compiler.processCompiledUnits(Compiler.java:575)
	at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:475)
	at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:426)
	at com.google.gwt.dev.javac.JdtCompiler.doCompile(JdtCompiler.java:1020)
	at com.google.gwt.dev.javac.CompilationStateBuilder$CompileMoreLater.compile(CompilationStateBuilder.java:322)
	at com.google.gwt.dev.javac.CompilationStateBuilder.doBuildFrom(CompilationStateBuilder.java:532)
	at com.google.gwt.dev.javac.CompilationStateBuilder.buildFrom(CompilationStateBuilder.java:464)
	at com.google.gwt.dev.cfg.ModuleDef.getCompilationState(ModuleDef.java:423)
	at com.google.gwt.dev.Precompile.precompile(Precompile.java:210)
	at com.google.gwt.dev.Precompile.precompile(Precompile.java:190)
	at com.google.gwt.dev.Precompile.precompile(Precompile.java:131)
	at com.google.gwt.dev.Compiler.compile(Compiler.java:192)
	at com.google.gwt.dev.Compiler.compile(Compiler.java:143)
	at com.google.gwt.junit.JUnitShell.compileForWebMode(JUnitShell.java:1093)
	at com.google.gwt.junit.JUnitShell.maybeCompileForWebMode(JUnitShell.java:1158)
	at com.google.gwt.junit.CompileStrategy.maybeCompileModuleImpl2(CompileStrategy.java:183)
	at com.google.gwt.junit.CompileStrategy.maybeCompileModuleImpl(CompileStrategy.java:113)
	at com.google.gwt.junit.SimpleCompileStrategy.maybeCompileModule(SimpleCompileStrategy.java:36)
	at com.google.gwt.junit.JUnitShell.runTestImpl(JUnitShell.java:1349)
	at com.google.gwt.junit.JUnitShell.runTestImpl(JUnitShell.java:1317)
	at com.google.gwt.junit.JUnitShell.runTest(JUnitShell.java:681)
	at com.google.gwt.junit.client.GWTTestCase.runTest(GWTTestCase.java:421)
	at junit.framework.TestCase.runBare(TestCase.java:141)
	at junit.framework.TestResult$1.protect(TestResult.java:122)
	at junit.framework.TestResult.runProtected(TestResult.java:142)
	at junit.framework.TestResult.run(TestResult.java:125)
	at junit.framework.TestCase.run(TestCase.java:129)
	at com.google.gwt.junit.client.GWTTestCase.run(GWTTestCase.java:247)
	at junit.framework.TestSuite.runTest(TestSuite.java:252)
	at junit.framework.TestSuite.run(TestSuite.java:247)
	at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:86)
	at org.junit.runners.Suite.runChild(Suite.java:128)
	at org.junit.runners.Suite.runChild(Suite.java:27)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
	at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
	at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
	at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
	at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:235)
	at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:54)
Caused by: java.lang.AssertionError
	at com.google.gwt.dev.javac.JdtUtil.signature(JdtUtil.java:369)
	at com.google.gwt.dev.jjs.impl.ReferenceMapper.get(ReferenceMapper.java:121)
	at com.google.gwt.dev.jjs.impl.GwtAstBuilder$AstVisitor.endVisit(GwtAstBuilder.java:641)
	... 60 more

When I run the debugger and put a breakpoint when this exception happens, I see that it is seems to be related to compiling DateTimeFormatterBuilder$LocalizedPrinterParser::toString

Is this a known issue ?

--- Class Scope ---
Member type : LocalizedPrinterParser (id=NoId)
static final class java.time.format.DateTimeFormatterBuilder$LocalizedPrinterParser
	extends java.lang.Object
	implements : java.time.format.DateTimeFormatterBuilder.DateTimePrinterParser
	enclosing type : java.time.format.DateTimeFormatterBuilder
/*   fields   */
private final java.time.format.FormatStyle dateStyle
private final java.time.format.FormatStyle timeStyle
/*   methods   */
void <init>(java.time.format.FormatStyle, java.time.format.FormatStyle) 
private java.time.format.DateTimeFormatter formatter(java.util.Locale, java.time.chrono.Chronology) 
public int parse(java.time.format.DateTimeParseContext, java.lang.CharSequence, int) 
public boolean print(java.time.format.DateTimePrintContext, java.lang.StringBuilder) 
public java.lang.String toString()

[dnouls]

It turns out that there is a problem with assertions in GWT 2.9/2.10 due to changes in JDT.
There will be a fix when the patch gets merged and a newer GWT is released.

[dnouls]

In the meantime it would be smart to refrain from using that ternary operation in the DateTimeFormatterBuilder@LocalizedPrinterParser::toString method.
It seems that you were already aware of this AST error problem some time ago since I saw you linked to this bug with a previous commit: gwtproject/gwt#9694

[foal]

Yes, I am already aware of this issue. Unfortunately, it is not a single place in the code that affected by this issue. So, for existing versions of GWT (2.9.0/2.10.0) I suggest to use the workaround - disable JVM asserts as it suggested in gwtproject/gwt#9694.

I will update the readme to mentioned that.