Puranjay Savar Mattas
6e1ffb96fd
Convert from git submodule to plain vendored copy. No push access to upstream nodes-app/swift-markdown-engine meant our local fix commit (05c1720) was stranded and unreachable from any remote on fresh clones/CI. Vendoring as plain files folds it into normal repo history instead.
75 lines
2.7 KiB
Swift
75 lines
2.7 KiB
Swift
//
|
||
// BottomOverscrollPolicyTests.swift
|
||
// MarkdownEngineTests
|
||
//
|
||
// Created by Luca Chen on 11.06.26.
|
||
//
|
||
// Bottom-overscroll math, in particular how the scroll-away header band
|
||
// participates in activation/unlock while the slack stays viewport-based.
|
||
//
|
||
|
||
import Foundation
|
||
import Testing
|
||
@testable import MarkdownEngine
|
||
|
||
@Suite("BottomOverscrollPolicy")
|
||
struct BottomOverscrollPolicyTests {
|
||
|
||
/// Engine defaults: percent 0.5, max 450, min 40, activation 0.15 + 0.85.
|
||
private let policy = BottomOverscrollPolicy(configuration: .default)
|
||
private let visible: CGFloat = 800
|
||
private let lineHeight: CGFloat = 26
|
||
|
||
@Test func shortTextWithoutBandGetsNoSlack() {
|
||
// Below the activation start (0.15 × 800 = 120): nothing to scroll.
|
||
let slack = policy.activeOverscroll(
|
||
baseContentHeight: 100, visibleHeight: visible, lineHeight: lineHeight
|
||
)
|
||
#expect(slack == 0)
|
||
}
|
||
|
||
@Test func emptyDocumentWithoutBandGetsNoSlack() {
|
||
let slack = policy.activeOverscroll(
|
||
baseContentHeight: 30, visibleHeight: visible, lineHeight: lineHeight
|
||
)
|
||
#expect(slack == 0)
|
||
}
|
||
|
||
@Test func expandedBandActivatesSlackForShortText() {
|
||
// Text alone is below the activation start (100 < 120), but the 550pt
|
||
// band pushes its end near the viewport bottom — slack must unlock.
|
||
let slack = policy.activeOverscroll(
|
||
baseContentHeight: 100, headerHeight: 550,
|
||
visibleHeight: visible, lineHeight: lineHeight
|
||
)
|
||
#expect(slack > 0)
|
||
// The document must actually overflow so the band can be scrolled away.
|
||
let scrollRange = 550 + 100 + slack - visible
|
||
#expect(scrollRange > 100)
|
||
}
|
||
|
||
@Test func fullyActivatedSlackIsBandIndependent() {
|
||
// At full activation the band has scrolled away — slack must not change.
|
||
// Defaults: floor(min(800 × 0.5, 450) − 26) = 374.
|
||
let without = policy.activeOverscroll(
|
||
baseContentHeight: 800, visibleHeight: visible, lineHeight: lineHeight
|
||
)
|
||
let with = policy.activeOverscroll(
|
||
baseContentHeight: 800, headerHeight: 550,
|
||
visibleHeight: visible, lineHeight: lineHeight
|
||
)
|
||
#expect(without == 374)
|
||
#expect(with == 374)
|
||
}
|
||
|
||
@Test func headerlessRampMatchesPreBandBehavior() {
|
||
// Locks the pre-header formula for plain editors (headerHeight = 0):
|
||
// progress = (500 − 120) / 680, unlock = 300, slack = 374
|
||
// → floor((300 + 374) × 0.55882…) = 376.
|
||
let slack = policy.activeOverscroll(
|
||
baseContentHeight: 500, visibleHeight: visible, lineHeight: lineHeight
|
||
)
|
||
#expect(slack == 376)
|
||
}
|
||
}
|