5c: match the mark set's nesting on both sides of the round-trip

src/adf/document.test.ts

@@ -61,14 +61,16 @@ test('rejects a node whose shape ProseMirror JSON cannot hold', () => {
 })
 
 test('names the attribute nesting past the levels the parser reads one at, and still calls the value a document', () => {
-  const deeper = (key: string, type: string): string => `the ${key} attribute of ${type} nests deeper than the ${largestNesting} levels an attribute carries`
+  const deeper = (key: string, type: string, levels: number = largestNesting): string =>
+    `the ${key} attribute of ${type} nests deeper than the ${levels} levels an attribute carries`
   assert.equal(fault(withAttribute(nested(largestNesting))), 'accepted')
   assert.equal(fault(withAttribute(nested(largestNesting + 1))), deeper('a', 'paragraph'))
   assert.equal(faultCode(withAttribute(nested(largestNesting + 1))), 'unsupported-nesting-depth')
   assert.equal(isAdfDocument(withAttribute(nested(largestNesting + 1))), true)
-  const marked = { content: [{ marks: [{ attrs: { a: nested(largestNesting + 1) }, type: 'link' }], text: 'x', type: 'text' }], type: 'doc', version: 1 }
-  assert.equal(fault(marked), deeper('a', 'link'))
-  assert.equal(isAdfDocument(marked), true)
+  const marked = (levels: number): unknown => ({ content: [{ marks: [{ attrs: { a: nested(levels) }, type: 'link' }], text: 'x', type: 'text' }], type: 'doc', version: 1 })
+  assert.equal(fault(marked(largestNesting - 3)), 'accepted')
+  assert.equal(fault(marked(largestNesting - 2)), deeper('a', 'link', largestNesting - 3))
+  assert.equal(isAdfDocument(marked(largestNesting - 2)), true)
 })
 
 test('accepts the JSON values an attribute may hold', () => {

src/adf/document.ts

@@ -23,6 +23,9 @@ export type AdfDocument = {
   version: number
 }
 
+// A block directive spells the whole mark set as one JSON attribute, so a mark's value sits three levels inside it.
+const markAttributeNesting = largestNesting - 3
+
 const documentKeys = ['content', 'type', 'version']
 const markKeys = ['attrs', 'type']
 const nodeKeys = ['attrs', 'content', 'marks', 'text', 'type']
@@ -44,8 +47,8 @@ export function adfDocumentFault(value: unknown): ConvertFault | undefined {
   return nestingFault(content)
 }
 
-export function attributeNestingMessage(key: string, type: string): string {
-  return `the ${key} attribute of ${type} nests deeper than the ${largestNesting} levels an attribute carries`
+export function attributeNestingMessage(key: string, type: string, levels: number = largestNesting): string {
+  return `the ${key} attribute of ${type} nests deeper than the ${levels} levels an attribute carries`
 }
 
 export function carriesOnly(node: AdfNode, attributes: readonly string[]): boolean {
@@ -101,15 +104,15 @@ function nestingFault(nodes: readonly AdfNode[]): ConvertFault | undefined {
 
 function marksFault(marks: readonly AdfMark[] | undefined): ConvertFault | undefined {
   for (const mark of marks ?? []) {
-    const fault = attributesFault(mark.attrs, mark.type)
+    const fault = attributesFault(mark.attrs, mark.type, markAttributeNesting)
     if (fault !== undefined) return fault
   }
   return undefined
 }
 
-function attributesFault(attrs: AdfAttributes | undefined, type: string): ConvertFault | undefined {
+function attributesFault(attrs: AdfAttributes | undefined, type: string, levels: number = largestNesting): ConvertFault | undefined {
   for (const [key, value] of Object.entries(attrs ?? {})) {
-    if (overNested(value)) return { code: 'unsupported-nesting-depth', message: attributeNestingMessage(key, type) }
+    if (overNested(value, levels)) return { code: 'unsupported-nesting-depth', message: attributeNestingMessage(key, type, levels) }
   }
   return undefined
 }

src/markdown/emit/adf-to-markdown.test.ts

@@ -336,19 +336,33 @@ test('refuses marks and attributes nested deeper than the emitter carries', () =
   assert.equal(code(adfToMarkdown(document(paragraph({ marks, text: 'x', type: 'text' })))), 'unsupported-nesting-depth')
   let attrs: AdfMark['attrs'] = { depth: 'x' }
   for (let depth = 0; depth < 600; depth += 1) attrs = { depth: attrs }
-  const deeper = (key: string, type: string): string =>
-    `unsupported-nesting-depth: the ${key} attribute of ${type} nests deeper than the ${largestNesting} levels an attribute carries`
-  assert.equal(markdown(adfToMarkdown(document(paragraph({ marks: [{ attrs, type: 'em' }], text: 'x', type: 'text' })))), deeper('depth', 'em'))
-  const card = (levels: number): AdfNode => {
-    let data: JsonValue = 1
-    for (let level = 0; level < levels; level += 1) data = [data]
-    return { attrs: { data, url: 'https://example.com/a' }, type: 'inlineCard' }
+  const deeper = (key: string, type: string, levels: number = largestNesting): string =>
+    `unsupported-nesting-depth: the ${key} attribute of ${type} nests deeper than the ${levels} levels an attribute carries`
+  const nested = (levels: number): JsonValue => {
+    let value: JsonValue = 1
+    for (let level = 0; level < levels; level += 1) value = [value]
+    return value
   }
+  const card = (levels: number): AdfNode => ({ attrs: { data: nested(levels), url: 'https://example.com/a' }, type: 'inlineCard' })
+  // A block directive spells the mark set as one JSON attribute, so a mark's value is read three levels in.
+  const marked = (levels: number): AdfNode => ({
+    attrs: { panelType: 'info' },
+    content: [paragraph({ text: 'x', type: 'text' })],
+    marks: [{ attrs: { deep: nested(levels) }, type: 'em' }],
+    type: 'panel',
+  })
+  const roundTrips = (node: AdfNode): void => {
+    const spelled = adfToMarkdown(document(node))
+    assert.ok(spelled.ok, spelled.ok ? '' : spelled.error.message)
+    assert.deepEqual(markdownToAdf(spelled.value), { ok: true, value: document(node) })
+  }
+
+  assert.equal(markdown(adfToMarkdown(document(paragraph({ marks: [{ attrs, type: 'em' }], text: 'x', type: 'text' })))), deeper('depth', 'em', largestNesting - 3))
   assert.equal(markdown(adfToMarkdown(document(paragraph(card(largestNesting + 1))))), deeper('data', 'inlineCard'))
   assert.deepEqual(path(adfToMarkdown(document(paragraph(card(largestNesting + 1))))), [])
-  const spelled = adfToMarkdown(document(paragraph(card(largestNesting))))
-  assert.ok(spelled.ok, spelled.ok ? '' : spelled.error.message)
-  assert.deepEqual(markdownToAdf(spelled.value), { ok: true, value: document(paragraph(card(largestNesting))) })
+  roundTrips(paragraph(card(largestNesting)))
+  assert.equal(markdown(adfToMarkdown(document(marked(largestNesting - 2)))), deeper('deep', 'em', largestNesting - 3))
+  roundTrips(marked(largestNesting - 3))
 })
 
 test('escapes a literal delimiter that would merge with an emitted one', () => {

src/markdown/parse/markdown-to-adf.test.ts

@@ -441,6 +441,7 @@ test('names the depth an attribute value nests past, never the kind the JSON rea
     `unsupported-nesting-depth: the ${key} attribute of ${type} nests deeper than the ${largestNesting} levels an attribute carries`
   assert.equal(content(markdownToAdf(`:::tableCell {colwidth="${nested(largestNesting + 1)}"}\n:::\n`)), deeper('colwidth', 'tableCell'))
   assert.equal(content(markdownToAdf(`::rule {marks="${nested(largestNesting + 1)}"}\n`)), deeper('marks', 'rule'))
+  assert.equal(content(markdownToAdf(`::rule {marks="[{\\"attrs\\":{\\"deep\\":${nested(largestNesting - 2)}},\\"type\\":\\"em\\"}]"}\n`)), deeper('marks', 'rule'))
   assert.equal(content(markdownToAdf(`::media {width="${nested(largestNesting + 1)}"}\n`)), 'unsupported-node-shape: the width attribute of media is no number')
 })