Add support for -no-warnings-as-errors

Author: owenv

Sources/SwiftDriver/Driver/Driver.swift

@@ -49,6 +49,7 @@ public struct Driver {
     case relativeFrontendPath(String)
     case subcommandPassedToDriver
     case integratedReplRemoved
+    case conflictingOptions(Option, Option)
 
     public var description: String {
       switch self {
@@ -65,6 +66,8 @@ public struct Driver {
         return "subcommand passed to driver"
       case .integratedReplRemoved:
         return "Compiler-internal integrated REPL has been removed; use the LLDB-enhanced REPL instead."
+      case .conflictingOptions(let one, let two):
+        return "conflicting options '\(one.spelling)' and '\(two.spelling)'"
       }
     }
   }
@@ -307,6 +310,8 @@ public struct Driver {
     self.numThreads = Self.determineNumThreads(&parsedOptions, compilerMode: compilerMode, diagnosticsEngine: diagnosticEngine)
     self.numParallelJobs = Self.determineNumParallelJobs(&parsedOptions, diagnosticsEngine: diagnosticEngine, env: env)
 
+    try Self.validateWarningControlArgs(&parsedOptions)
+
     // Compute debug information output.
     (self.debugInfoLevel, self.debugInfoFormat, shouldVerifyDebugInfo: self.shouldVerifyDebugInfo) =
       Self.computeDebugInfo(&parsedOptions, diagnosticsEngine: diagnosticEngine)
@@ -1457,6 +1462,16 @@ extension Diagnostic.Message {
   }
 }
 
+// MARK: Miscellaneous Argument Validation
+extension Driver {
+  static func validateWarningControlArgs(_ parsedOptions: inout ParsedOptions) throws {
+    if parsedOptions.hasArgument(.suppressWarnings) &&
+        parsedOptions.hasFlag(positive: .warningsAsErrors, negative: .noWarningsAsErrors, default: false) {
+      throw Error.conflictingOptions(.warningsAsErrors, .suppressWarnings)
+    }
+  }
+}
+
 extension Triple {
   func toolchainType(_ diagnosticsEngine: DiagnosticsEngine) throws -> Toolchain.Type {
     switch os {

Sources/SwiftDriver/Jobs/FrontendJobHelpers.swift

@@ -118,7 +118,7 @@ extension Driver {
     try commandLine.appendLast(.profileGenerate, from: &parsedOptions)
     try commandLine.appendLast(.profileUse, from: &parsedOptions)
     try commandLine.appendLast(.profileCoverageMapping, from: &parsedOptions)
-    try commandLine.appendLast(.warningsAsErrors, from: &parsedOptions)
+    try commandLine.appendLast(.warningsAsErrors, .noWarningsAsErrors, from: &parsedOptions)
     try commandLine.appendLast(.sanitizeCoverageEQ, from: &parsedOptions)
     try commandLine.appendLast(.static, from: &parsedOptions)
     try commandLine.appendLast(.swiftVersion, from: &parsedOptions)

Tests/SwiftDriverTests/SwiftDriverTests.swift

@@ -1545,6 +1545,39 @@ final class SwiftDriverTests: XCTestCase {
     }
   }
 
+  func testDiagnosticOptions() throws {
+    do {
+      var driver = try Driver(args: ["swift", "-no-warnings-as-errors", "-warnings-as-errors", "foo.swift"])
+      let plannedJobs = try driver.planBuild()
+      XCTAssertEqual(plannedJobs.count, 1)
+      let job = plannedJobs[0]
+      XCTAssertTrue(job.commandLine.contains(.flag("-warnings-as-errors")))
+    }
+
+    do {
+      var driver = try Driver(args: ["swift", "-warnings-as-errors", "-no-warnings-as-errors", "foo.swift"])
+      let plannedJobs = try driver.planBuild()
+      XCTAssertEqual(plannedJobs.count, 1)
+      let job = plannedJobs[0]
+      XCTAssertTrue(job.commandLine.contains(.flag("-no-warnings-as-errors")))
+    }
+
+    do {
+      var driver = try Driver(args: ["swift", "-warnings-as-errors", "-no-warnings-as-errors", "-suppress-warnings", "foo.swift"])
+      let plannedJobs = try driver.planBuild()
+      XCTAssertEqual(plannedJobs.count, 1)
+      let job = plannedJobs[0]
+      XCTAssertTrue(job.commandLine.contains(.flag("-no-warnings-as-errors")))
+      XCTAssertTrue(job.commandLine.contains(.flag("-suppress-warnings")))
+    }
+
+    do {
+      XCTAssertThrowsError(try Driver(args: ["swift", "-no-warnings-as-errors", "-warnings-as-errors", "-suppress-warnings", "foo.swift"])) {
+        XCTAssertEqual($0 as? Driver.Error, Driver.Error.conflictingOptions(.warningsAsErrors, .suppressWarnings))
+      }
+    }
+  }
+
   func testPCHGeneration() throws {
     do {
       var driver = try Driver(args: ["swiftc", "-typecheck", "-import-objc-header", "TestInputHeader.h", "foo.swift"])