Fix scala runner exit codes

[rochala]

Adoption of scala2 exit code implementation. Fixes #15022

Now main runner returns proper status code when it fails during runtime.
Also tried to cleanup this class a bit.

I added tests for all combinations of MainGenericCompiler / Runner that I could think of and found that -print-tasty flag was returning wrong exit codes despite errors. I didn't know it that's the best place to put them but i think they count as scripting tests.

The last change that I've made is improving error messages for scala expressions (-e). Before it created virtual files from compileFromStrings even though we explicitly passed one source. It lead to very high horizontal length of stack trace making it less clear as those files had UUID in their name. It now creates single file to make it shorter.

Exception in thread "main" java.lang.RuntimeException
        at compileFromString$minus86740691$minus6469$minus484b$minusaf4f$minus40ffc988311b$package$.main(compileFromString-86740691-6469-484b-af4f-40ffc988311b.scala:2)
        at main.main(compileFromString-86740691-6469-484b-af4f-40ffc988311b.scala:1)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:568)
        at dotty.tools.scripting.StringDriver.compileAndRun(StringDriver.scala:36)
        at dotty.tools.MainGenericRunner$.run$1(MainGenericRunner.scala:258)
        at dotty.tools.MainGenericRunner$.main(MainGenericRunner.scala:268)
        at dotty.tools.MainGenericRunner.main(MainGenericRunner.scala)

[rochala]

I'll delete this additional file after fixes in code review to not rerun tests again. touchedFile.out

[rochala]

I found that touchedFile.out was a leftover from this test. Now it should be deleted properly.

changes were made as requested

[bishabosha]

minor point but it would be nice if for ExecuteMode.Expression the StringDriver.compileAndRun was escaped for the StringDriverException to just print the message, like what happens for ScriptingException.

Currently we get a stack trace for compilation errors in the -e mode:

~/workspace/scripts » ../dotty/dist/target/pack/bin/scala -e 'prinln(2)' || echo "fail"
-- [E006] Not Found Error: expression:2:2 --------------------------------------
2 |  prinln(2)
  |  ^^^^^^
  |  Not found: prinln
  |
  | longer explanation available when compiling with `-explain`
dotty.tools.scripting.StringDriverException: Errors encountered during compilation
	at dotty.tools.scripting.StringDriverException$.apply(StringDriver.scala:52)
	at dotty.tools.scripting.StringDriver.compileAndRun(StringDriver.scala:31)
	at dotty.tools.MainGenericRunner$.run$1(MainGenericRunner.scala:261)
	at dotty.tools.MainGenericRunner$.process(MainGenericRunner.scala:271)
	at dotty.tools.MainGenericRunner$.main(MainGenericRunner.scala:281)
	at dotty.tools.MainGenericRunner.main(MainGenericRunner.scala)
fail

Ideally it would just be

~/workspace/scripts » ../dotty/dist/target/pack/bin/scala -e 'prinln(2)' || echo "fail"
-- [E006] Not Found Error: expression:2:2 --------------------------------------
2 |  prinln(2)
  |  ^^^^^^
  |  Not found: prinln
  |
  | longer explanation available when compiling with `-explain`
Errors encountered during compilation
fail

[rochala]

Yeah, my mistake, and while we're at expression flag. In scala 2 -e flag is called as execute while here it's called expression. Shouldn't scala3 match scala2 naming ?

[bishabosha]

while we're at expression flag. In scala 2 -e flag is called as execute while here it's called expression. Shouldn't scala3 match scala2 naming ?

I would say no: - I don't think its a big deal because its internal details, but could also cause confusion with other modes, such as ExecuteMode.Run