Different output depending on compilation with intellij or sbt - scala

Question

I have the following scala program that simply counts the words in a file:
package com.impatient
import java.util.Scanner
object Main extends App {
countWords()
def countWords(): Unit = {
val in = new Scanner(new java.io.File("C:\\tmp\\SampleText.txt"))
var wc = 0
while (in.hasNext()) {
var word = in.next()
wc += 1
println( wc + ". " + word)
}
in.close()
println("======================")
println(s"Total words: $wc")
}
def TestFunction(): Unit ={
println("Hello from test function!")
}
TestFunction()
}
When I execute this in intellij, either directly or via the sbt shell inside intellij, I get the following output:
mostly
positive:
======================
Total words: 309
Hello from test function!
So it correctly counts 309 words in the text file.
However if I try to execute the jar that I just compiled with intellij, directly, either via scala or sbt I get the following output:
λ scala .\impatientscala2_2.12-1.0.jar
======================
Total words: 0
Hello from test function!
So in this case, although the methods in Main are executed the wordcount is 0.
Why would be this the case? Is intellij referencing some other java libraries that standalone sbt or scala isn't? In that case why doesn't the Scanner fail?
Edit 1
I have cloned this repo to another PC to see what happens. And in that case I can observe the exact opposite, i.e.:
The program returns 0 word count when run from Intellij
When the jar is run directly with scala, it gives the current wordcount.
The 0 wordcount is due to not processing the while loop, as in.hasNext() returns nothing.

Answer 1

I found a workaround by using Paths.get from java.nio.file._.
//val in = new Scanner(new java.io.File("C:/tmp/SampleText.txt"))
val in: Scanner = new Scanner(Paths.get("C/tmp/SampleText.txt"))
This produces the correct jars on both PCs, when using Run | Sbt Task in Intellij, using SBT Shell in intellij, and using standalone SBT shell. If anyone can provide an explanation of why would java.io.File fail in certain setups that would be great.