CLI gives null-pointer exception

[edwardalee]

The following valid LF program gives an NPE coming from the CLI code.
Contents of file ExtendsBugInside.lf:

target C
reactor C(
    period: time(5 ms)
) {
    timer t(0, period)
}

reactor A(
    period: time(5 ms)
) {    
    a = new C(period = period)
}

Contents of file ExtendsBug.lf:

target C

import A from "ExtendsBugInside.lf"

reactor B extends A {}

main reactor {
    a = new B()
}

Result of trying to compile:

ealmac:C eal$ lfc src/rosace/ExtendsBug.lf 
lfc: fatal error: An unexpected error occurred:
java.lang.NullPointerException: Cannot invoke "org.eclipse.emf.common.util.URI.isPlatform()" because "uri" is null
	at org.lflang.util.FileUtil.toIPath(FileUtil.java:88)
	at org.lflang.util.FileUtil.toPath(FileUtil.java:71)
	at org.lflang.cli.CliBase.validateResource(CliBase.java:225)
	at org.lflang.cli.Lfc.invokeGenerator(Lfc.java:193)
	at org.lflang.cli.Lfc.run(Lfc.java:165)
	at picocli.CommandLine.executeUserObject(CommandLine.java:2026)
	at picocli.CommandLine.access$1500(CommandLine.java:148)
	at picocli.CommandLine$RunLast.executeUserObjectOfLastSubcommandWithSameParent(CommandLine.java:2461)
	at picocli.CommandLine$RunLast.handle(CommandLine.java:2453)
	at picocli.CommandLine$RunLast.handle(CommandLine.java:2415)
	at picocli.CommandLine$AbstractParseResultHandler.execute(CommandLine.java:2273)
	at picocli.CommandLine$RunLast.execute(CommandLine.java:2417)
	at picocli.CommandLine.execute(CommandLine.java:2170)
	at org.lflang.cli.CliBase.cliMain(CliBase.java:103)
	at org.lflang.cli.Lfc.main(Lfc.java:150)
	at org.lflang.cli.Lfc.main(Lfc.java:140)

[cmnrd]

The NPE is fixed by #1655. However, this NPE occurred in the error reporting and only masked another problem. With #1655, I get this output:

lfc: error: Error executing EValidator


lfc: fatal error: Aborting due to 1 previous error.

This indicates an exception in the validator. Unfortunately, the validator does not tell us where it occurs...

However, the problem disappears with #1580. I am not sure if it is an actual fix to the problem or just masking it though.