Create ParsingCheck

Package.swift

@@ -36,6 +36,13 @@ let package = Package(
                 "XMLCoder",
             ]
         ),
+        .executableTarget(
+            name: "ParsingCheck",
+            dependencies: [
+                "XcbeautifyLib",
+                .product(name: "ArgumentParser", package: "swift-argument-parser"),
+            ]
+        ),
         .testTarget(
             name: "XcbeautifyLibTests",
             dependencies: ["XcbeautifyLib"],

Sources/ParsingCheck/ParsingCheck.swift

@@ -0,0 +1,48 @@
+import ArgumentParser
+import Darwin
+import Foundation
+import XcbeautifyLib
+
+@main
+struct ParsingCheck: ParsableCommand {
+
+    @Option
+    var filePath: String
+
+    @Option
+    var uncapturedOutput: Int
+
+    enum ParsingCheckError: Error {
+        case dataReadError
+        case noData
+        case regression(Int)
+    }
+
+    func run() throws {
+        guard let data = FileManager.default.contents(atPath: filePath) else {
+            throw ParsingCheckError.noData
+        }
+
+        guard !data.isEmpty else {
+            throw ParsingCheckError.noData
+        }
+
+        var buildLog: [String] = String(decoding: data, as: UTF8.self)
+            .components(separatedBy: .newlines)
+
+        let parser = Parser()
+
+        var uncapturedOutput = 0
+
+        while !buildLog.isEmpty {
+            let line = buildLog.removeFirst()
+            if !line.isEmpty, parser.parse(line: line) == nil {
+                uncapturedOutput += 1
+            }
+        }
+
+        guard self.uncapturedOutput == uncapturedOutput else {
+            throw ParsingCheckError.regression(uncapturedOutput)
+        }
+    }
+}