[GROOVY-9213] Parser runs (possibly) endless loop for unclosed parenthesis followed by many expressions/statements

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: parser-antlr2, parser-antlr4
• Assignee: Unassigned
• Reporter: Eric Milles
• Created: 05/Aug/19 16:49
• Updated: 05/Aug/19 17:22

Description

Consider the following:

int a = 0
// insert ( here instead of this comment and try to select anything below
a = 0
a = 0
a = 0
... (like 50 times)

With the unmatched parenthesis inserted at line 2, there is a loop in the parser looking for command arguments.

Here is a test case that demonstrates:

import groovy.transform.CompileStatic
import org.codehaus.groovy.control.CompilerConfiguration
import org.junit.Test

import static org.codehaus.groovy.control.ParserPluginFactory.antlr2
import static org.codehaus.groovy.control.ParserPluginFactory.antlr4

@CompileStatic
final class Groovy9213 {

    @Test(timeout=15000L)
    void testUnmatchedParenInLongScript2() {
        def config = new CompilerConfiguration()
        config.pluginFactory = antlr2()

        new GroovyShell(config).evaluate('''
            int a = 0
            (
        ''' + ('a = 0\n' * 50))
    }

    @Test(timeout=15000L)
    void testUnmatchedParenInLongScript4() {
        def config = new CompilerConfiguration()
        config.pluginFactory = antlr4(config)

        new GroovyShell(config).evaluate('''
            int a = 0
            (
        ''' + ('a = 0\n' * 50))
    }
}

This is a problem for users editing Groovy scripts in the IDE: https://github.com/groovy/groovy-eclipse/issues/932