[Bug]: Ambiguous compiler error when instantiating a class that does not exist

[hasathcharu]

Description

When a class is instantiated with the new keyword, if you give a class that does not exist, the thrown compiler error is vague and causes a Bad Sad error. The project folder has a red dot marked on VS Code without an indication as to which file the error is stemming from. The resulting compiler error also points to the first line, first column of the bal file.

• VS Code Screen
  Here, note that the class db does not exist.

• Console Error Log

[2024-05-08 11:54:37,574] SEVERE {b7a.log.crash} - Cannot read field "flags" because "type.tsymbol" is null 
java.lang.NullPointerException: Cannot read field "flags" because "type.tsymbol" is null
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:2809)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:286)
        at org.wso2.ballerinalang.compiler.tree.expressions.BLangTypeInit.accept(BLangTypeInit.java:70)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.analyzeExpr(CodeAnalyzer.java:3605)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:3296)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:286)
        at org.wso2.ballerinalang.compiler.tree.expressions.BLangCheckedExpr.accept(BLangCheckedExpr.java:70)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.analyzeExpr(CodeAnalyzer.java:3605)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:1838)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:286)
        at org.wso2.ballerinalang.compiler.tree.statements.BLangAssignment.accept(BLangAssignment.java:86)
        at org.wso2.ballerinalang.compiler.tree.SimpleBLangNodeAnalyzer.visitNode(SimpleBLangNodeAnalyzer.java:217)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.analyzeNode(CodeAnalyzer.java:355)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:544)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:286)
        at org.wso2.ballerinalang.compiler.tree.BLangBlockFunctionBody.accept(BLangBlockFunctionBody.java:65)
        at org.wso2.ballerinalang.compiler.tree.SimpleBLangNodeAnalyzer.visitNode(SimpleBLangNodeAnalyzer.java:217)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.analyzeNode(CodeAnalyzer.java:355)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visitFunction(CodeAnalyzer.java:519)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:462)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:286)
        at org.wso2.ballerinalang.compiler.tree.BLangFunction.accept(BLangFunction.java:82)
        at org.wso2.ballerinalang.compiler.tree.SimpleBLangNodeAnalyzer.visitNode(SimpleBLangNodeAnalyzer.java:217)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.analyzeNode(CodeAnalyzer.java:355)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.analyzeTopLevelNodes(CodeAnalyzer.java:344)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:332)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.visit(CodeAnalyzer.java:286)
        at org.wso2.ballerinalang.compiler.tree.BLangPackage.accept(BLangPackage.java:172)
        at org.wso2.ballerinalang.compiler.tree.SimpleBLangNodeAnalyzer.visitNode(SimpleBLangNodeAnalyzer.java:217)
        at org.wso2.ballerinalang.compiler.semantics.analyzer.CodeAnalyzer.analyze(CodeAnalyzer.java:320)
        at io.ballerina.projects.internal.CompilerPhaseRunner.codeAnalyze(CompilerPhaseRunner.java:192)
        at io.ballerina.projects.internal.CompilerPhaseRunner.performTypeCheckPhases(CompilerPhaseRunner.java:115)
        at io.ballerina.projects.ModuleContext.compileInternal(ModuleContext.java:435)
        at io.ballerina.projects.ModuleCompilationState$1.compile(ModuleCompilationState.java:45)
        at io.ballerina.projects.ModuleContext.compile(ModuleContext.java:383)
        at io.ballerina.projects.PackageCompilation.compileModulesInternal(PackageCompilation.java:211)
        at io.ballerina.projects.PackageCompilation.compileModules(PackageCompilation.java:195)
        at io.ballerina.projects.PackageCompilation.compile(PackageCompilation.java:102)
        at io.ballerina.projects.PackageCompilation.from(PackageCompilation.java:97)
        at io.ballerina.projects.PackageContext.getPackageCompilation(PackageContext.java:244)
        at io.ballerina.projects.Package.getCompilation(Package.java:150)
        at io.ballerina.projects.Package.runCodeGeneratorPlugins(Package.java:323)
        at io.ballerina.cli.task.CompileTask.execute(CompileTask.java:153)
        at io.ballerina.cli.TaskExecutor.executeTasks(TaskExecutor.java:40)
        at io.ballerina.cli.cmd.RunCommand.execute(RunCommand.java:258)
        at java.base/java.util.Optional.ifPresent(Optional.java:178)
        at io.ballerina.cli.launcher.Main.main(Main.java:58)
 
ERROR [proj:(1:1,1:1)] Compilation failed due to: Cannot read field "flags" because "type.tsymbol" is null
error: compilation contains errors

Steps to Reproduce

• Create a new ballerina project
• Instantiate a class that does not exist

public function main() returns error? {
    _ = check new db ();
}

Affected Version(s)

Ballerina Swan Lake Update 09

OS, DB, other environment details and versions

OS: Ubuntu 22.04.4 LTS
VS Code Version: 1.88.1
Ballerina VS Code Extension: v4.6.0

Related area

-> Compilation

Related issue(s) (optional)

No response

Suggested label(s) (optional)

No response

Suggested assignee(s) (optional)

No response