It seems to be a common mistake to write "foo: bar" instead of "foo = bar" in build scripts. For example:

compile("junit:junit:4.8.2") {
  transitive: false // should be: transitive = false
}

Since Groovy interprets "transitive:" as a label, it won't complain and the error will be hard to find. People are used to the "foo: bar" syntax because Gradle makes heavy use of named parameters.

To avoid this trap, we could write an AST transform that forbids the use of labels in build scripts.