Files
personotes/frontend/node_modules/@lezer/markdown/test/test-incremental.ts

260 lines
8.2 KiB
TypeScript

import {Tree, TreeFragment} from "@lezer/common"
import ist from "ist"
import {parser} from "../dist/index.js"
import {compareTree} from "./compare-tree.js"
let doc1 = `
Header
---
One **two**
three *four*
five.
> Start of quote
>
> 1. Nested list
>
> 2. More content
> inside the [list][link]
>
> Continued item
>
> ~~~
> Block of code
> ~~~
>
> 3. And so on
[link]: /ref
[another]: /one
And a final paragraph.
***
The end.
`
type ChangeSpec = {from: number, to?: number, insert?: string}[]
class State {
constructor(readonly doc: string,
readonly tree: Tree,
readonly fragments: readonly TreeFragment[]) {}
static start(doc: string) {
let tree = parser.parse(doc)
return new State(doc, tree, TreeFragment.addTree(tree))
}
update(changes: ChangeSpec, reparse = true) {
let changed = [], doc = this.doc, off = 0
for (let {from, to = from, insert = ""} of changes) {
doc = doc.slice(0, from) + insert + doc.slice(to)
changed.push({fromA: from - off, toA: to - off, fromB: from, toB: from + insert.length})
off += insert.length - (to - from)
}
let fragments = TreeFragment.applyChanges(this.fragments, changed, 2)
if (!reparse) return new State(doc, Tree.empty, fragments)
let tree = parser.parse(doc, fragments)
return new State(doc, tree, TreeFragment.addTree(tree, fragments))
}
}
let _state1: State | null = null, state1 = () => _state1 || (_state1 = State.start(doc1))
function overlap(a: Tree, b: Tree) {
let inA = new Set<Tree>(), shared = 0, sharingTo = 0
for (let cur = a.cursor(); cur.next();) if (cur.tree) inA.add(cur.tree)
for (let cur = b.cursor(); cur.next();) if (cur.tree && inA.has(cur.tree) && cur.type.is("Block") && cur.from >= sharingTo) {
shared += cur.to - cur.from
sharingTo = cur.to
}
return Math.round(shared * 100 / b.length)
}
function testChange(change: ChangeSpec, reuse = 10) {
let state = state1().update(change)
compareTree(state.tree, parser.parse(state.doc))
if (reuse) ist(overlap(state.tree, state1().tree), reuse, ">")
}
describe("Markdown incremental parsing", () => {
it("can produce the proper tree", () => {
// Replace 'three' with 'bears'
let state = state1().update([{from: 24, to: 29, insert: "bears"}])
compareTree(state.tree, state1().tree)
})
it("reuses nodes from the previous parse", () => {
// Replace 'three' with 'bears'
let state = state1().update([{from: 24, to: 29, insert: "bears"}])
ist(overlap(state1().tree, state.tree), 80, ">")
})
it("can reuse content for a change in a block context", () => {
// Replace 'content' with 'monkeys'
let state = state1().update([{from: 92, to: 99, insert: "monkeys"}])
compareTree(state.tree, state1().tree)
ist(overlap(state1().tree, state.tree), 20, ">")
})
it("can handle deleting a quote mark", () => testChange([{from: 82, to: 83}]))
it("can handle adding to a quoted block", () => testChange([{from: 37, insert: "> "}, {from: 45, insert: "> "}]))
it("can handle a change in a post-linkref paragraph", () => testChange([{from: 249, to: 251}]))
it("can handle a change in a paragraph-adjacent linkrefs", () => testChange([{from: 230, to: 231}]))
it("can deal with multiple changes applied separately", () => {
let state = state1().update([{from: 190, to: 191}], false).update([{from: 30, insert: "hi\n\nyou"}])
compareTree(state.tree, parser.parse(state.doc))
ist(overlap(state.tree, state1().tree), 20, ">")
})
it("works when a change happens directly after a block", () => testChange([{from: 150, to: 167}]))
it("works when a change deletes a blank line after a paragraph", () => testChange([{from: 207, to: 213}]))
it("doesn't get confused by removing paragraph-breaking markup", () => testChange([{from: 264, to: 265}]))
function r(n: number) { return Math.floor(Math.random() * n) }
function rStr(len: number) {
let result = "", chars = "\n>x-"
while (result.length < len) result += chars[r(chars.length)]
return result
}
it("survives random changes", () => {
for (let i = 0, l = doc1.length; i < 20; i++) {
let c = 1 + r(4), changes = []
for (let i = 0, rFrom = 0; i < c; i++) {
let rTo = rFrom + Math.floor((l - rFrom) / (c - i))
let from = rFrom + r(rTo - rFrom - 1), to = r(2) == 1 ? from : from + r(Math.min(rTo - from, 20))
let iR = r(3), insert = iR == 0 && from != to ? "" : iR == 1 ? "\n\n" : rStr(r(5) + 1)
changes.push({from, to, insert})
l += insert.length - (to - from)
rFrom = to + insert.length
}
testChange(changes, 0)
}
})
it("can handle large documents", () => {
let doc = doc1.repeat(50)
let state = State.start(doc)
let newState = state.update([{from: doc.length >> 1, insert: "a\n\nb"}])
ist(overlap(state.tree, newState.tree), 90, ">")
})
it("properly re-parses a continued indented code block", () => {
let state = State.start(`
One paragraph to create a bit of string length here
Code
Block
Another paragraph that is long enough to create a fragment
`).update([{from: 76, insert: " "}])
compareTree(state.tree, parser.parse(state.doc))
})
it("properly re-parses a continued list", () => {
let state = State.start(`
One paragraph to create a bit of string length here
* List
More content
Another paragraph that is long enough to create a fragment
`).update([{from: 65, insert: " * "}])
compareTree(state.tree, parser.parse(state.doc))
})
it("can recover from incremental parses that stop in the middle of a list", () => {
let doc = `
1. I am a list item with ***some* emphasized
content inside** and the parser hopefully stops
parsing after me.
2. Oh no the list continues.
`
let parse = parser.startParse(doc), tree
parse.advance()
ist(parse.parsedPos, doc.length, "<")
parse.stopAt(parse.parsedPos)
while (!(tree = parse.advance())) {}
let state = new State(doc, tree, TreeFragment.addTree(tree)).update([])
ist(state.tree.topNode.lastChild!.from, 1)
})
it("can reuse list items", () => {
let start = State.start(" - List item\n".repeat(100))
let state = start.update([{from: 18, to: 19}])
ist(overlap(start.tree, state.tree), 80, ">")
})
it("returns a tree starting at the first range", () => {
let result = parser.parse("foo\n\nbar", [], [{from: 5, to: 8}])
ist(result.toString(), "Document(Paragraph)")
ist(result.length, 3)
ist(result.positions[0], 0)
})
it("Allows gaps in the input", () => {
let doc = `
The first X *y* X<
>X paragraph.
- And *a X<*>X list*
`
let tree = parser.parse(doc, [], [{from: 0, to: 11}, {from: 12, to: 17}, {from: 23, to: 46}, {from: 51, to: 58}])
ist(tree.toString(),
"Document(Paragraph(Emphasis(EmphasisMark,EmphasisMark)),BulletList(ListItem(ListMark,Paragraph(Emphasis(EmphasisMark,EmphasisMark)))))")
ist(tree.length, doc.length)
let top = tree.topNode, first = top.firstChild!
ist(first.name, "Paragraph")
ist(first.from, 1)
ist(first.to, 34)
let last = top.lastChild!.lastChild!.lastChild!, em = last.lastChild!
ist(last.name, "Paragraph")
ist(last.from, 39)
ist(last.to, 57)
ist(em.name, "Emphasis")
ist(em.from, 43)
ist(em.to, 57)
})
it("can reuse nodes at the end of the document", () => {
let doc = `* List item
~~~js
function foo() {
return false
}
~~~
`
let tree = parser.parse(doc)
let ins = 11
let doc2 = doc.slice(0, ins) + "\n* " + doc.slice(ins)
let fragments = TreeFragment.applyChanges(TreeFragment.addTree(tree), [{fromA: ins, toA: ins, fromB: ins, toB: ins + 3}])
let tree2 = parser.parse(doc2, fragments)
ist(tree2.topNode.lastChild!.tree, tree.topNode.lastChild!.tree)
})
it("places reused nodes at the right position when there are gaps before them", () => {
let doc = " {{}}\nb\n{{}}"
let ast1 = parser.parse(doc, undefined, [{from: 0, to: 1}, {from: 5, to: 8}])
let frag = TreeFragment.applyChanges(TreeFragment.addTree(ast1), [{fromA: 0, toA: 0, fromB: 0, toB: 1}])
let ast2 = parser.parse(" " + doc, frag, [{from: 0, to: 2}, {from: 6, to: 9}])
ist(ast2.toString(), "Document(Paragraph)")
let p = ast2.topNode.firstChild!
ist(p.from, 7)
ist(p.to, 8)
})
})