Remove unnecessary test helpers

src/Test/FiddlingWithSyntaxTree/Document.create.ts

@@ -1,9 +1,8 @@
 import { expect } from 'chai'
 import * as Up from '../../Main'
-import { cast } from '../Helpers'
 
 
-const NOT_USED = cast<string>(null)
+const NOT_USED: string = null!
 
 context('The `Document.create` method is automatically used during the normal parsing process. It returns a document object with:', () => {
   specify('A table of contents', () => {

src/Test/Html/Escaping/AttributeValue.ts

@@ -1,6 +1,5 @@
 import { expect } from 'chai'
 import * as Up from '../../../Main'
-import { cast } from '../../Helpers'
 
 
 context('Within any attribute value, all instances of " and & are escaped. Specifically, within the', () => {
@@ -186,7 +185,7 @@ context('Within any attribute value, all instances of " and & are escaped. Speci
       }
     })
 
-    const NOT_USED = cast<string>(null)
+    const NOT_USED: string = null!
 
     const heading =
       new Up.Heading([new Up.Text('I enjoy apples')], {

src/Test/Html/Escaping/Content.ts

@@ -1,6 +1,5 @@
 import { expect } from 'chai'
 import * as Up from '../../../Main'
-import { cast } from '../../Helpers'
 
 
 describe('Within a text node, all instances of < and &', () => {
@@ -293,7 +292,7 @@ describe("Within an audio convention's fallback link content, all instances of <
 
 
 context('Within a table of contents entry, all instances of < and & are escaped:', () => {
-  const NOT_USED = cast<string>(null)
+  const NOT_USED: string = null!
 
   specify('In the table of contents itself', () => {
     const heading =

src/Test/Html/IdWordDelimiting.ts

@@ -1,9 +1,8 @@
 import { expect } from 'chai'
 import * as Up from '../../Main'
-import { cast } from '../Helpers'
 
 
-const NOT_USED = cast<string>(null)
+const NOT_USED: string = null!
 
 context('Words within HTML IDs are delimited by hyphens.', () => {
   context('This applies to terms appearing in IDs:', () => {

src/Test/Html/Links/NestedLink.ts

@@ -1,9 +1,8 @@
 import { expect } from 'chai'
 import * as Up from '../../../Main'
-import { cast } from '../../Helpers'
 
 
-const NOT_USED = cast<string>(null)
+const NOT_USED: string = null!
 
 context('Inside a link', () => {
   specify("a footnote does not produce another <a> element. The footnote's <sup> directly contains the footnote's reference number", () => {

src/Test/Html/Settings/Changes.ts

@@ -1,6 +1,5 @@
 import { expect } from 'chai'
 import * as Up from '../../../Main'
-import { cast } from '../../Helpers'
 
 
 function itCanBeProvidedMultipleWaysWithTheSameResult(
@@ -138,7 +137,7 @@ describe('The "footnote" term', () => {
 
 
 describe('The "sectionReferencedByTableOfContents" setting', () => {
-  const NOT_USED = cast<string>(null)
+  const NOT_USED: string = null!
 
   const heading = new Up.Heading([], { level: 1, titleMarkup: NOT_USED })
 

src/Test/Html/Settings/IdPrefix.ts

@@ -1,6 +1,5 @@
 import { expect } from 'chai'
 import * as Up from '../../../Main'
-import { cast } from '../../Helpers'
 
 
 describe("A footnote reference's ID (as well as the ID of the footnote it points to)", () => {
@@ -352,7 +351,7 @@ describe('The IDs and names of elements rendered for revealable blocks', () => {
 })
 
 
-const NOT_USED = cast<string>(null)
+const NOT_USED: string = null!
 
 describe('The ID of an element referenced by the table of contents', () => {
   it("is prefixed with the default ID prefix 'up' if one wasn't provided", () => {

src/Test/Html/Settings/SectionReferencedByTableOfContents.ts

@@ -1,6 +1,5 @@
 import { expect } from 'chai'
 import * as Up from '../../../Main'
-import { cast } from '../../Helpers'
 
 
 describe('The ID of an element referenced by the table of contents', () => {
@@ -11,7 +10,7 @@ describe('The ID of an element referenced by the table of contents', () => {
       }
     })
 
-    const NOT_USED = cast<string>(null)
+    const NOT_USED: string = null!
 
     const heading =
       new Up.Heading([new Up.Text('I enjoy apples')], {

src/Test/Html/SingleNode.ts

@@ -1,9 +1,8 @@
 import { expect } from 'chai'
 import * as Up from '../../Main'
-import { cast } from '../Helpers'
 
 
-const NOT_USED = cast<string>(null)
+const NOT_USED: string = null!
 
 describe('An empty document', () => {
   it('does not produce any HTML on its own', () => {

src/Test/Html/SourceMap.ts

@@ -1,6 +1,5 @@
 import { expect } from 'chai'
 import * as Up from '../../Main'
-import { cast } from '../Helpers'
 
 
 context('When an outline syntax node has a source line number, its outermost element is given an "data-up-source-line" attribute whose value is the line number. This is true for:', () => {
@@ -239,7 +238,7 @@ context('When an outline syntax node has a source line number, its outermost ele
       + '</blockquote>')
   })
 
-  const NOT_USED = cast<string>(null)
+  const NOT_USED: string = null!
 
   specify('Level 1 headings', () => {
     const document = new Up.Document([

src/Test/Html/TableOfContents.ts

@@ -1,9 +1,8 @@
 import { expect } from 'chai'
 import * as Up from '../../Main'
-import { cast } from '../Helpers'
 
 
-const NOT_USED = cast<string>(null)
+const NOT_USED: string = null!
 
 specify('When a document has no table of contents entries, the table of contents renders a blank string', () => {
   const document =

src/Test/Parsing/Image.ts

@@ -190,7 +190,7 @@ describe("An image convention's URL", () => {
 })
 
 
-describe('An image description (enclosed in square brackets)', () => {
+describe('An image description enclosed in square brackets', () => {
   it('can contain matching square brackets', () => {
     expect(Up.parse('[image: haunted [house]](http://example.com/?state=NE)')).to.deep.equal(
       new Up.Document([
@@ -207,7 +207,7 @@ describe('An image description (enclosed in square brackets)', () => {
 })
 
 
-describe('An image description (enclosed by parentheses)', () => {
+describe('An image description enclosed in parentheses', () => {
   it('can contain matching parentheses', () => {
     expect(Up.parse('(image: ghosts eating (luggage))[http://example.com/?state=NE]')).to.deep.equal(
       new Up.Document([

src/Test/Parsing/NumberedList/Order.ts

@@ -140,13 +140,8 @@ context('When the starting ordinal is negative', () => {
 
 
 function expectListOrderToBe(order: Up.NumberedList.Order, numberedListMarkup: string): void {
-  expect(listOrder(numberedListMarkup)).to.equal(order)
-}
-
-
-function listOrder(numberedListMarkup: string): Up.NumberedList.Order {
   const list =
     Up.parse(numberedListMarkup).children[0] as Up.NumberedList
 
-  return list.order()
+  expect(list.order()).to.equal(order)
 }

src/Test/Parsing/Settings/ChangesToKeywords.ts

@@ -1,7 +1,6 @@
 import { expect } from 'chai'
 import { distinct } from '../../../Implementation/CollectionHelpers'
 import * as Up from '../../../Main'
-import { cast } from '../../Helpers'
 import { settingsFor } from './Helpers'
 
 
@@ -217,8 +216,10 @@ function itCanBeProvidedMultipleWaysWithTheSameResult(
 }
 
 
-const NULL_KEYWORD = cast<string>(null)
-const UNDEFINED_KEYWORD = cast<string>(undefined)
+// The API doesn't officially accept `null` or `undefined` keywords, but we'll
+// nonetheless ensure they politely ignored.
+const NULL_KEYWORD: string = null!
+const UNDEFINED_KEYWORD: string = undefined!
 
 describe('The "audio" keyword', () => {
   itCanBeProvidedMultipleWaysWithTheSameResult({