WIP diagnostics: tests

Author: Jesse Haigh

Sources/SwiftDocC/Checker/Checkers/InvalidCodeBlockOption.swift

@@ -49,9 +49,15 @@ public struct InvalidCodeBlockOption: Checker {
             let matches = NearMiss.bestMatches(for: knownOptions, against: token)
 
             if !matches.isEmpty {
-                let diagnostic = Diagnostic(source: sourceFile, severity: .warning, range: codeBlock.range, identifier: "org.swift.docc.InvalidCodeBlockOption", summary: "Unknown option \(token) in code block. Did you mean \(matches)?", explanation: nil)
+                let diagnostic = Diagnostic(source: sourceFile, severity: .warning, range: codeBlock.range, identifier: "org.swift.docc.InvalidCodeBlockOption", summary: "Unknown option \(token.singleQuoted) in code block.")
+                let possibleSolutions = matches.map { candidate in
+                    Solution(
+                        summary: "Replace \(token.singleQuoted) with \(candidate.singleQuoted).",
+                        replacements: []
+                    )
+                }
                 // FIXME: figure out the position of 'token' and provide solutions
-                problems.append(Problem(diagnostic: diagnostic, possibleSolutions: []))
+                problems.append(Problem(diagnostic: diagnostic, possibleSolutions: possibleSolutions))
             }
         }
     }

Tests/SwiftDocCTests/Checker/Checkers/InvalidCodeBlockOptionTests.swift

@@ -0,0 +1,95 @@
+/*
+ This source file is part of the Swift.org open source project
+
+ Copyright (c) 2025 Apple Inc. and the Swift project authors
+ Licensed under Apache License v2.0 with Runtime Library Exception
+
+ See https://swift.org/LICENSE.txt for license information
+ See https://swift.org/CONTRIBUTORS.txt for Swift project authors
+*/
+
+import XCTest
+@testable import SwiftDocC
+import Markdown
+
+class InvalidCodeBlockOptionTests: XCTestCase {
+
+    func testOption() {
+        let markupSource = """
+```nocopy
+let a = 1
+```
+"""
+        let document = Document(parsing: markupSource, options: [])
+        var checker = InvalidCodeBlockOption(sourceFile: nil)
+        checker.visit(document)
+        XCTAssertTrue(checker.problems.isEmpty)
+    }
+
+    func testMultipleOptionTypos() {
+        let markupSource = """
+```nocoy
+let b = 2
+```
+
+```nocoy
+let c = 3
+```
+"""
+        let document = Document(parsing: markupSource, options: [])
+        var checker = InvalidCodeBlockOption(sourceFile: URL(fileURLWithPath: #file))
+        checker.visit(document)
+        XCTAssertEqual(2, checker.problems.count)
+
+        for problem in checker.problems {
+            XCTAssertEqual("org.swift.docc.InvalidCodeBlockOption", problem.diagnostic.identifier)
+            XCTAssertEqual(problem.diagnostic.summary, "Unknown option 'nocoy' in code block.")
+            XCTAssertEqual(problem.possibleSolutions.map(\.summary), ["Replace 'nocoy' with 'nocopy'."])
+        }
+    }
+
+    func testOptionDifferentTypos() throws {
+        let markupSource = """
+```swift, nocpy
+let d = 4
+```         
+
+```unknown, nocpoy
+let e = 5
+```
+
+```nocopy
+let f = 6
+```   
+
+```ncopy
+let g = 7
+```  
+"""
+        let document = Document(parsing: markupSource, options: [])
+        var checker = InvalidCodeBlockOption(sourceFile: URL(fileURLWithPath: #file))
+        checker.visit(document)
+
+        XCTAssertEqual(3, checker.problems.count)
+
+        let summaries = checker.problems.map { $0.diagnostic.summary }
+        XCTAssertEqual(summaries, [
+            "Unknown option 'nocpy' in code block.",
+            "Unknown option 'nocpoy' in code block.",
+            "Unknown option 'ncopy' in code block.",
+        ])
+
+        for problem in checker.problems {
+            XCTAssertEqual(
+                "org.swift.docc.InvalidCodeBlockOption",
+                problem.diagnostic.identifier
+            )
+
+            XCTAssertEqual(problem.possibleSolutions.count, 1)
+            let solution = try XCTUnwrap(problem.possibleSolutions.first)
+            XCTAssert(solution.summary.hasSuffix("with 'nocopy'."))
+
+        }
+    }
+}
+