Fix parsing block equations with leading/trailing newlines and update tests.

Author: colinc86

Sources/LaTeXSwiftUI/Models/Parser.swift

@@ -49,28 +49,28 @@ internal struct Parser {
 
   /// An TeX-style block equation component.
   static let tex = EquationComponent(
-    regex: #/\$\$(.*?)\$\$/#,
+    regex: #/\$\$\s*(.*?)\s*\$\$/#,
     terminatingRegex: #/\$\$/#,
     equation: .texEquation,
     supportsRecursion: false)
 
   /// A block equation.
   static let block = EquationComponent(
-    regex: #/\\\[(.*?)\\\]/#,
+    regex: #/\\\[\s*(.*?)\s*\\\]/#,
     terminatingRegex: #/\\\]/#,
     equation: .blockEquation,
     supportsRecursion: false)
 
   /// A named equation component.
   static let named = EquationComponent(
-    regex: #/\\begin{equation}(.*?)\\end{equation}/#,
+    regex: #/\\begin{equation}\s*(.*?)\s*\\end{equation}/#,
     terminatingRegex: #/\\end{equation}/#,
     equation: .namedEquation,
     supportsRecursion: true)
 
   /// A named no number equation component.
   static let namedNoNumber = EquationComponent(
-    regex: #/\\begin{equation\*}(.*?)\\end{equation\*}/#,
+    regex: #/\\begin{equation\*}\s*(.*?)\s*\\end{equation\*}/#,
     terminatingRegex: #/\\end{equation\*}/#,
     equation: .namedNoNumberEquation,
     supportsRecursion: true)

…aTeXSwiftUITests/LaTeXSwiftUITests.swift …ts/LaTeXSwiftUITests/GeometryTests.swiftTests/LaTeXSwiftUITests/LaTeXSwiftUITests.swift renamed to Tests/LaTeXSwiftUITests/GeometryTests.swift Tests/LaTeXSwiftUITests/LaTeXSwiftUITests.swift renamed to Tests/LaTeXSwiftUITests/GeometryTests.swift

@@ -2,7 +2,7 @@ import MathJaxSwift
 import XCTest
 @testable import LaTeXSwiftUI
 
-final class LaTeXSwiftUITests: XCTestCase {
+final class GeometryTests: XCTestCase {
 
   func testSVGGeometry_parseAlignment() {
     let input = "\"vertical-align: -1.602ex;\""

Tests/LaTeXSwiftUITests/ParserTests.swift

@@ -92,6 +92,30 @@ final class ParserTests: XCTestCase {
     assertComponent(components, 0, input, .text)
   }
 
+  func testParseDoubleDollarOnly_LeadingLineBreak() {
+    let equation = "\nf(x)=5x+2"
+    let input = "$$\(equation)$$"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 1)
+    assertComponent(components, 0, equation, .texEquation)
+  }
+  
+  func testParseDoubleDollarOnly_TrailingLineBreak() {
+    let equation = "f(x)=5x+2\n"
+    let input = "$$\(equation)$$"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 1)
+    assertComponent(components, 0, equation, .texEquation)
+  }
+  
+  func testParseDoubleDollarOnly_Whitespace() {
+    let equation = " \nf(x)=5x+2\n "
+    let input = "$$\(equation)$$"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 1)
+    assertComponent(components, 0, equation, .texEquation)
+  }
+  
   func testParseBracketsOnly() {
     let input = "\\[\\TeX\\]"
     let components = Parser.parse(input)
@@ -122,11 +146,28 @@ final class ParserTests: XCTestCase {
     assertComponent(components, 0, input, .text)
   }
 
-  func testParseBracketsOnly_LineBreak() {
-    let input = "Hello, \\[\\TeX\n\\\\]!"
+  func testParseBracketsOnly_LeadingLineBreak() {
+    let equation = "\n\\TeX"
+    let input = "Hello, \\[\(equation)\\]!"
     let components = Parser.parse(input)
-    XCTAssertEqual(components.count, 1)
-    assertComponent(components, 0, input, .text)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .blockEquation)
+  }
+  
+  func testParseBracketsOnly_TrailingLineBreak() {
+    let equation = "\\TeX\n"
+    let input = "Hello, \\[\(equation)\\]!"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .blockEquation)
+  }
+  
+  func testParseBracketsOnly_Whitespace() {
+    let equation = " \n\\TeX\n "
+    let input = "Hello, \\[\(equation)\\]!"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .blockEquation)
   }
 
   func testParseBeginEndOnly() {
@@ -159,11 +200,28 @@ final class ParserTests: XCTestCase {
     assertComponent(components, 0, input, .text)
   }
 
-  func testParseBeginEndOnly_LineBreak() {
-    let input = "Hello, \\begin{equation}\\TeX\n\\\\end{equation}!"
+  func testParseBeginEndOnly_LeadingLineBreak() {
+    let equation = "\n\\TeX"
+    let input = "Hello, \\begin{equation}\(equation)\\end{equation}!"
     let components = Parser.parse(input)
-    XCTAssertEqual(components.count, 1)
-    assertComponent(components, 0, input, .text)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .namedEquation)
+  }
+  
+  func testParseBeginEndOnly_TrailingLineBreak() {
+    let equation = "\\TeX\n"
+    let input = "Hello, \\begin{equation}\(equation)\\end{equation}!"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .namedEquation)
+  }
+  
+  func testParseBeginEndOnly_Whitespace() {
+    let equation = " \n\\TeX\n "
+    let input = "Hello, \\begin{equation}\(equation)\\end{equation}!"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .namedEquation)
   }
 
   func testParseBeginEndStarOnly() {
@@ -196,11 +254,28 @@ final class ParserTests: XCTestCase {
     assertComponent(components, 0, input, .text)
   }
 
-  func testParseBeginEndStarOnly_LineBreak() {
-    let input = "Hello, \\begin{equation*}\\TeX\n\\\\end{equation*}!"
+  func testParseBeginEndStarOnly_LeadingLineBreak() {
+    let equation = "\n\\TeX"
+    let input = "Hello, \\begin{equation*}\(equation)\\end{equation*}!"
     let components = Parser.parse(input)
-    XCTAssertEqual(components.count, 1)
-    assertComponent(components, 0, input, .text)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .namedNoNumberEquation)
+  }
+  
+  func testParseBeginEndStarOnly_TrailingLineBreak() {
+    let equation = "\\TeX\n"
+    let input = "Hello, \\begin{equation*}\(equation)\\end{equation*}!"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .namedNoNumberEquation)
+  }
+  
+  func testParseBeginEndStarOnly_Whitespace() {
+    let equation = " \n\\TeX\n "
+    let input = "Hello, \\begin{equation*}\(equation)\\end{equation*}!"
+    let components = Parser.parse(input)
+    XCTAssertEqual(components.count, 3)
+    assertComponent(components, 1, equation, .namedNoNumberEquation)
   }
 
 }