Context receivers give `ParseError`

[bddckr]

Context receivers give `ParseError`

[davidtorosyan]

@bddckr I don't think #314 indicates that ktfmt used to support context receivers.

Rather, any situations in which they work right now are incidental. In that issue, they're parsed but not formatted correctly.

In your example, they're not parsed at all.

---

Normally I'd close this as a duplicate, but the fact that this causes a crash (instead of just bad formatting) means we should consider a mitigation at least (if a full fix is hard).

@strulovich has there been any investigation into this?

[bddckr]

Adding this to TokenizerTest shows the issue:

@Test
fun `Context receivers are parsed correctly`() {
  val code = """
    |class A {
    |  context(String)
    |  fun test() {}
    |}
    |""".trimMargin().trimMargin()

  val file = Parser.parse(code)
  val tokenizer = Tokenizer(code, file)
  file.accept(tokenizer)

  assertThat(tokenizer.toks.map { it.originalText })
          .containsExactly("class", " ", "A", " ", "{", "\n", "  ", "context", "(", "String", ")", "\n", "  ", "fun", " ", "test", "(", ")", " ", "{", "}", "\n", "}")
          .inOrder()
  assertThat(tokenizer.toks.map { it.index })
          .containsExactly(0, -1, 1, -1, 2, -1, -1, 3, 4, 5, 6, -1, -1, 7, -1, 8, 9, 10, -1, 11, 12, -1, 13)
          .inOrder()
}

Changing pom.xml to use <kotlin.version>1.6.20-M1</kotlin.version> makes that test pass.

However, this is where my knowledge ends 😅 Adding this to FormatterTest shows that further changes are required to support context receivers, just like #314 explains.

@Test
fun `context receivers`() =
  assertFormatted(
      """
    |class A {
    |  context(String)
    |  fun test() {}
    |}
    |"""
          .trimMargin())