@testable import PureYAML
import Testing

/// A compact nested block sequence (`- - x`) carries no indent/dedent tokens, only block entries at
/// their columns. A sequence collects sibling items only at its own column, so a later entry at a
/// smaller column ends it and belongs to the enclosing sequence: `- - x` then `- - y` is `[[x], [y]]`,
/// two outer items, not one outer item holding both.
@Suite("Compact nested sequence")
struct CompactNestedSequenceTests {
    @Test("Two compact nested entries are two outer items")
    func test_twoNestedItems() throws {
        #expect(try PureYAML.parse("- - x\n- - y\n") == .sequence([
            .sequence([.string("x")]),
            .sequence([.string("y")]),
        ]))
    }

    @Test("Three levels of compact nesting separate at the outer column")
    func test_threeLevels() throws {
        #expect(try PureYAML.parse("- - - []\n- - - {}\n") == .sequence([
            .sequence([.sequence([.sequence([])])]),
            .sequence([.sequence([.mapping(.init([]))])]),
        ]))
    }

    @Test("Entries at the same column stay one sequence")
    func test_sameColumnSiblings() throws {
        #expect(try PureYAML.parse("- - a\n  - b\n") == .sequence([
            .sequence([.string("a"), .string("b")]),
        ]))
    }

    @Test("A flat sequence is unchanged")
    func test_flatSequence() throws {
        #expect(try PureYAML.parse("- a\n- b\n") == .sequence([.string("a"), .string("b")]))
    }
}