Merge pull request swiftlang#162 from dylansturg/ignore_unparsable_files

Add `ignore-unparsable-files` to silence diagnostics for invalid syntax

Author: allevato

Sources/swift-format/CommandLineOptions.swift

@@ -71,6 +71,16 @@ struct SwiftFormatCommand: ParsableCommand {
     help: "Recursively run on '.swift' files in any provided directories.")
   var recursive: Bool
 
+  /// Whether unparsable files, due to syntax errors or unrecognized syntax, should be ignored or
+  /// treated as containing an error. When ignored, unparsable files are output verbatim in format
+  /// mode and no diagnostics are raised in lint mode. When not ignored, unparsable files raise a
+  /// diagnostic in both format and lint mode.
+  @Flag(help: """
+    Ignores unparsable files, disabling all diagnostics and formatting for files that contain \
+    invalid syntax.
+    """)
+  var ignoreUnparsableFiles: Bool
+
   /// The list of paths to Swift source files that should be formatted or linted.
   @Argument(help: "One or more input filenames")
   var paths: [String]

Sources/swift-format/Run.swift

@@ -24,12 +24,13 @@ import TSCBasic
 ///   - configuration: The `Configuration` that contains user-specific settings.
 ///   - sourceFile: A file handle from which to read the source code to be linted.
 ///   - assumingFilename: The filename of the source file, used in diagnostic output.
+///   - ignoreUnparsableFiles: Whether or not to ignore files that contain syntax errors.
 ///   - debugOptions: The set containing any debug options that were supplied on the command line.
 ///   - diagnosticEngine: A diagnostic collector that handles diagnostic messages.
 /// - Returns: Zero if there were no lint errors, otherwise a non-zero number.
 func lintMain(
   configuration: Configuration, sourceFile: FileHandle, assumingFilename: String?,
-  debugOptions: DebugOptions, diagnosticEngine: DiagnosticEngine
+  ignoreUnparsableFiles: Bool, debugOptions: DebugOptions, diagnosticEngine: DiagnosticEngine
 ) {
   let linter = SwiftLinter(configuration: configuration, diagnosticEngine: diagnosticEngine)
   linter.debugOptions = debugOptions
@@ -49,6 +50,9 @@ func lintMain(
       Diagnostic.Message(.error, "Unable to lint \(path): file is not readable or does not exist."))
     return
   } catch SwiftFormatError.fileContainsInvalidSyntax(let position) {
+    guard !ignoreUnparsableFiles else {
+      return
+    }
     let path = assumingFileURL.path
     let location = SourceLocationConverter(file: path, source: source).location(for: position)
     diagnosticEngine.diagnose(
@@ -69,12 +73,13 @@ func lintMain(
 ///   - sourceFile: A file handle from which to read the source code to be linted.
 ///   - assumingFilename: The filename of the source file, used in diagnostic output.
 ///   - inPlace: Whether or not to overwrite the current file when formatting.
+///   - ignoreUnparsableFiles: Whether or not to ignore files that contain syntax errors.
 ///   - debugOptions: The set containing any debug options that were supplied on the command line.
 ///   - diagnosticEngine: A diagnostic collector that handles diagnostic messages.
 /// - Returns: Zero if there were no format errors, otherwise a non-zero number.
 func formatMain(
   configuration: Configuration, sourceFile: FileHandle, assumingFilename: String?, inPlace: Bool,
-  debugOptions: DebugOptions, diagnosticEngine: DiagnosticEngine
+  ignoreUnparsableFiles: Bool, debugOptions: DebugOptions, diagnosticEngine: DiagnosticEngine
 ) {
   // Even though `diagnosticEngine` is defined, it's use is reserved for fatal messages. Pass nil
   // to the formatter to suppress other messages since they will be fixed or can't be automatically
@@ -111,6 +116,15 @@ func formatMain(
         .error, "Unable to format \(path): file is not readable or does not exist."))
     return
   } catch SwiftFormatError.fileContainsInvalidSyntax(let position) {
+    guard !ignoreUnparsableFiles else {
+      guard !inPlace else {
+        // For in-place mode, nothing is expected to stdout and the file shouldn't be modified.
+        return
+      }
+      stdoutStream.write(source)
+      stdoutStream.flush()
+      return
+    }
     let path = assumingFileURL.path
     let location = SourceLocationConverter(file: path, source: source).location(for: position)
     diagnosticEngine.diagnose(

Sources/swift-format/main.swift

@@ -10,13 +10,13 @@
 //
 //===----------------------------------------------------------------------===//
 
+import ArgumentParser
 import Foundation
 import SwiftFormat
 import SwiftFormatConfiguration
 import SwiftFormatCore
 import SwiftSyntax
 import TSCBasic
-import ArgumentParser
 
 extension SwiftFormatCommand {
   func run() throws {
@@ -29,36 +29,44 @@ extension SwiftFormatCommand {
         formatMain(
           configuration: configuration, sourceFile: FileHandle.standardInput,
           assumingFilename: assumeFilename, inPlace: false,
+          ignoreUnparsableFiles: ignoreUnparsableFiles,
           debugOptions: debugOptions, diagnosticEngine: diagnosticEngine)
       } else {
-        try processSources(from: paths, configurationPath: configurationPath, diagnosticEngine: diagnosticEngine) {
+        try processSources(
+          from: paths, configurationPath: configurationPath, diagnosticEngine: diagnosticEngine
+        ) {
           (sourceFile, path, configuration) in
           formatMain(
             configuration: configuration, sourceFile: sourceFile, assumingFilename: path,
-            inPlace: inPlace, debugOptions: debugOptions, diagnosticEngine: diagnosticEngine)
+            inPlace: inPlace, ignoreUnparsableFiles: ignoreUnparsableFiles,
+            debugOptions: debugOptions, diagnosticEngine: diagnosticEngine)
         }
       }
-      
+
     case .lint:
       if paths.isEmpty {
         let configuration = try loadConfiguration(
           forSwiftFile: nil, configFilePath: configurationPath)
         lintMain(
-            configuration: configuration, sourceFile: FileHandle.standardInput,
-            assumingFilename: assumeFilename, debugOptions: debugOptions, diagnosticEngine: diagnosticEngine)
+          configuration: configuration, sourceFile: FileHandle.standardInput,
+          assumingFilename: assumeFilename, ignoreUnparsableFiles: ignoreUnparsableFiles,
+          debugOptions: debugOptions, diagnosticEngine: diagnosticEngine)
       } else {
-        try processSources(from: paths, configurationPath: configurationPath, diagnosticEngine: diagnosticEngine) {
+        try processSources(
+          from: paths, configurationPath: configurationPath, diagnosticEngine: diagnosticEngine
+        ) {
           (sourceFile, path, configuration) in
           lintMain(
             configuration: configuration, sourceFile: sourceFile, assumingFilename: path,
+            ignoreUnparsableFiles: ignoreUnparsableFiles,
             debugOptions: debugOptions, diagnosticEngine: diagnosticEngine)
         }
       }
-      
+
     case .dumpConfiguration:
       try dumpDefaultConfiguration()
     }
-    
+
     // If any of the operations have generated diagnostics, exit with the
     // error status code.
     if !diagnosticEngine.diagnostics.isEmpty {
@@ -140,7 +148,8 @@ private func dumpDefaultConfiguration() throws {
     guard let jsonString = String(data: data, encoding: .utf8) else {
       // This should never happen, but let's make sure we fail more gracefully than crashing, just
       // in case.
-      throw FormatError(message: "Could not dump the default configuration: the JSON was not valid UTF-8")
+      throw FormatError(
+        message: "Could not dump the default configuration: the JSON was not valid UTF-8")
     }
     print(jsonString)
   } catch {