Gradle generateGrammarSource task isn't working - gradle

Question

I want to generate antlr4 lexer using gradle generateGrammarSource task.
Path to g4 file is src/main/antlr4/my/package/mygrammar.g4
I tried to use some examples I found so build.gradle has the following code:
buildscript {
ext.kotlin_version = '1.3.20'
repositories {
mavenCentral()
}
dependencies {
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
}
}
group 'my.package'
version '1.0-SNAPSHOT'
apply plugin: 'kotlin'
apply plugin: 'antlr'
repositories {
mavenCentral()
}
dependencies {
compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
compile group: 'org.antlr', name: 'antlr4', version: '4.7.2'
testCompile "org.jetbrains.kotlin:kotlin-test-junit:$kotlin_version"
}
generateGrammarSource {
arguments += ['-package', 'my.package']
}
compileKotlin {
kotlinOptions.jvmTarget = "1.8"
}
compileTestKotlin {
kotlinOptions.jvmTarget = "1.8"
}
Executing generateGrammarSource task generates nothing and gives the following output:
:generateGrammarSource NO-SOURCE
BUILD SUCCESSFUL in 0s
How can I fix it?

Answer 1

you need to create directory src/main/antlr and add Kotlin grammar files into there. most likely the my/package/ is the reason why it cannot find the grammar files; while this answers hints for, to add generated sources to the source-set. see The ANTLR Plugin.