Rewrite interfaces to scala for Scala Native

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/PositionException.scala

@@ -0,0 +1,37 @@
+package org.scalafmt.interfaces
+
+import java.nio.file.Path
+
+/** An exception that happened at a position in a source file such as a parse
+  * error.
+  */
+abstract class PositionException(message: String, cause: Throwable)
+    extends Exception(message, cause) {
+
+  override def fillInStackTrace(): Throwable = synchronized(this)
+
+  /** @return
+    *   The file where the error occurred.
+    */
+  def file(): Path
+
+  /** @return
+    *   The text contents of the file being formatted.
+    */
+  def code(): String
+
+  /** @return
+    *   The fully formatted error message including line content and caret.
+    */
+  def longMessage(): String
+
+  /** @return
+    *   Only the error message itself without line content and caret.
+    */
+  def shortMessage(): String
+
+  def startLine(): Int
+  def startCharacter(): Int
+  def endLine(): Int
+  def endCharacter(): Int
+}

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/RepositoryCredential.scala

@@ -0,0 +1,13 @@
+package org.scalafmt.interfaces
+
+final class RepositoryCredential(
+    val host: String,
+    val username: String,
+    val password: String,
+)
+
+object RepositoryCredential {
+  trait ScalafmtExtension {
+    def withRepositoryCredentials(credentials: RepositoryCredential*): Scalafmt
+  }
+}

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/Scalafmt.scala

@@ -0,0 +1,143 @@
+package org.scalafmt.interfaces
+
+import java.nio.file.Path
+import java.util
+import java.util.NoSuchElementException
+import java.util.ServiceLoader
+
+/** A stable public interface to run Scalafmt.
+  *
+  * This interface is designed for integrations such as editor plugins and build
+  * tools. An implementation of this interface is available in the module
+  * 'scalafmt-dynamic'.
+  *
+  * It is recommended to use this interface over the org.scalafmt.Scalafmt
+  * object for several reasons:
+  *
+  *   - this API is guaranteed to be binary compatible with all future versions
+  *     of Scalafmt.
+  *   - it downloads the Scalafmt version matching the 'version' setting in
+  *     .scalafmt.conf. All versions down to v1.2.0 are supported.
+  *   - it respects the 'project.{excludeFilters,includeFilters}' setting in
+  *     .scalafmt.conf.
+  *   - it uses the correct parser for `*.sbt` and `*.sc` files.
+  *   - it automatically caches parsing of configuration files avoiding
+  *     redundant work when possible.
+  *   - it has two external library dependencies (com.geirsson:coursier-small
+  *     and com.typesafe:config), which is a smaller dependency footprint
+  *     compared to scalafmt-core.
+  */
+trait Scalafmt {
+
+  /** Format a single file with the given .scalafmt.conf configuration.
+    *
+    * @param config
+    *   the absolute path to the configuration file. This file must exist or an
+    *   exception will be thrown.
+    * @param file
+    *   relative or absolute path to the file being formatted. Used only for the
+    *   path name, the file does not have to exist on disk.
+    * @param code
+    *   the text contents to format.
+    * @return
+    *   the formatted contents if formatting was successful, otherwise the
+    *   original text contents.
+    */
+  def format(config: Path, file: Path, code: String): String
+
+  /** Builder method.
+    *
+    * @param respectExcludeFilters
+    *   If true (default), returns the original file contents when formatting a
+    *   file that does not matches the project settings in .scalafmt.conf. If
+    *   false, formats every file that is passed to the
+    *   {@link #format(Path, Path, String)} method regardless of .scalafmt.conf
+    *   settings.
+    * @return
+    *   an updated interface instance controlling whether to respect the
+    *   'project.{excludeFilters,includeFilters}' setting in .scalafmt.conf.
+    */
+  def withRespectProjectFilters(respectExcludeFilters: Boolean): Scalafmt
+
+  /** Builder method.
+    *
+    * @param respectVersion
+    *   If true (default), refuses to format files when the 'version' setting is
+    *   missing in .scalafmt.conf and users must update .scalafmt.conf to format
+    *   files. If false, falls back to the default version provided via
+    *   {@link #withDefaultVersion(String)} .
+    * @return
+    *   an updated interface instance controlling whether to respect the
+    *   'version' setting in .scalafmt.conf.
+    */
+  @Deprecated
+  def withRespectVersion(respectVersion: Boolean): Scalafmt
+
+  /** Builder method.
+    *
+    * @param defaultVersion
+    *   the fallback Scalafmt version to use when there is no 'version' setting
+    *   in `.scalafmt.conf`; N.B. ignored when
+    *   {@link #withRespectVersion(boolean)} is true
+    * @return
+    *   an updated interface instance with the default version set
+    */
+  @Deprecated
+  def withDefaultVersion(defaultVersion: String): Scalafmt
+
+  /** Builder method.
+    *
+    * @param reporter
+    *   Use this instance to report errors and information messages
+    * @return
+    *   an updated interface instance with the reporter instance set
+    */
+  def withReporter(reporter: ScalafmtReporter): Scalafmt
+
+  /** Builder method.
+    *
+    * @param repositories
+    *   maven repositories to use when resolving
+    * @return
+    *   an updated interface instance with the repositories to use to resolve
+    *   dependencies.
+    */
+  def withMavenRepositories(repositories: String*): Scalafmt
+
+  /** Builder method.
+    *
+    * @param credentials
+    *   repository credentials to use when resolving
+    * @return
+    *   an updated interface instance.
+    */
+  def withRepositoryCredentials(credentials: RepositoryCredential*): Scalafmt
+
+  /** Clear internal caches such as classloaded Scalafmt instances.
+    */
+  def clear(): Unit
+
+  /** Create a ScalafmtSession to format a batch of files using fixed
+    * configuration.
+    * @param config
+    *   location of the configuration file
+    * @return
+    *   a new session instance
+    */
+  def createSession(config: Path): ScalafmtSession
+}
+
+object Scalafmt {
+
+  /** Classload a new instance of this Scalafmt instance.
+    *
+    * @param loader
+    *   the classloader containing the 'scalafmt-dynamic' module.
+    * @return
+    *   a new instance of this interface
+    * @throws NoSuchElementException
+    *   if the classloader does not have the 'scalafmt-dynamic' module.
+    */
+  def create(loader: ClassLoader): Scalafmt =
+    throw new Exception("Can't use different version for native CLI")
+}

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/ScalafmtClassLoader.scala

@@ -0,0 +1,16 @@
+package org.scalafmt.interfaces
+
+/** A classloader that shares only scalafmt-interfaces classes from the parent
+  * classloader.
+  *
+  * This classloader is intended to be used as a parent when class-loading
+  * scalafmt-dynamic. By using this classloader as a parent, it's possible to
+  * cast runtime instances from the scalafmt-dynamic classloader into
+  * `org.scalafmt.interfaces.Scalafmt` from this classloader.
+  */
+class ScalafmtClassLoader(val parent: ClassLoader) extends ClassLoader(null) {
+  @throws[ClassNotFoundException]
+  override protected def findClass(name: String): Class[_] =
+    if (name.startsWith("org.scalafmt.interfaces")) parent.loadClass(name)
+    else super.findClass(name)
+}

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/ScalafmtException.scala

@@ -0,0 +1,4 @@
+package org.scalafmt.interfaces
+
+class ScalafmtException(message: String, cause: Throwable)
+    extends RuntimeException(message, cause, true, false)

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/ScalafmtReporter.scala

@@ -0,0 +1,91 @@
+package org.scalafmt.interfaces
+
+import java.io.OutputStreamWriter
+import java.io.PrintWriter
+import java.nio.file.Path
+
+/** A reporter to handle error and information messages from Scalafmt.
+  */
+trait ScalafmtReporter {
+
+  /** An error occurred while trying to process this file.
+    *
+    * @param file
+    *   can be either a Scala source file or .scalafmt.conf.
+    * @param message
+    *   the error message.
+    */
+  def error(file: Path, message: String): Unit
+
+  /** An exception occurred while trying to process this file.
+    *
+    * @param file
+    *   can be either a Scala source file or .scalafmt.conf.
+    * @param e
+    *   the exception that occurred, has type {@link PositionException} when the
+    *   error appeared as a position.
+    */
+  def error(file: Path, e: Throwable): Unit
+
+  /** An exception occurred while trying to process this file.
+    *
+    * @param file
+    *   can be either a Scala source file or .scalafmt.conf.
+    * @param message
+    *   additional error message
+    * @param e
+    *   the exception that occurred, has type {@link PositionException} when the
+    *   error appeared as a position.
+    */
+  def error(file: Path, message: String, e: Throwable): Unit =
+    if (e == null) error(file, message)
+    else error(file, new ScalafmtException(message, e))
+
+  /** This file was not formatted because it's excluded by project settings from
+    * .scalafmt.conf.
+    *
+    * @param file
+    *   the file path that was not formatted.
+    */
+  def excluded(file: Path): Unit
+
+  /** This .scalafmt.conf file is missing the 'version' setting.
+    *
+    * @param config
+    *   the .scalafmt.conf file.
+    * @param defaultVersion
+    *   the configured default Scalafmt version.
+    */
+  def missingVersion(config: Path, defaultVersion: String): Unit = {
+    val message = String.format(
+      "missing setting 'version'. To fix this problem, add the following line to .scalafmt.conf: 'version=%s'.",
+      defaultVersion,
+    )
+    error(config, message)
+  }
+
+  /** Record the configuration file and version used
+    *
+    * @param config
+    *   location of the configuration file parsed
+    * @param scalafmtVersion
+    *   the version of scalafmt used to parse
+    */
+  def parsedConfig(config: Path, scalafmtVersion: String): Unit
+
+  /** Use {@link #downloadOutputStreamWriter} instead.
+    *
+    * @return
+    *   an instance of progress writer
+    */
+  @deprecated
+  def downloadWriter(): PrintWriter
+
+  /** Use this writer for printing progress while downloading new Scalafmt
+    * versions.
+    *
+    * @return
+    *   an instance of progress writer
+    */
+  def downloadOutputStreamWriter(): OutputStreamWriter
+}

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/ScalafmtResult.scala

@@ -0,0 +1,6 @@
+package org.scalafmt.interfaces
+
+final class ScalafmtResult(val value: String, val exception: Throwable) {
+  def this(value: String) = this(value, null)
+  def this(exception: Throwable) = this(null, exception)
+}

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/ScalafmtSession.scala

@@ -0,0 +1,47 @@
+package org.scalafmt.interfaces
+
+import java.nio.file.Path
+
+/** A session based on a fixed configuration.
+  */
+trait ScalafmtSession {
+
+  /** Format a single file with the given configuration.
+    *
+    * @param file
+    *   relative or absolute path to the file being formatted. Used only for the
+    *   path name, the file does not have to exist on disk.
+    * @param code
+    *   the text contents to format.
+    * @return
+    *   the formatted contents if formatting was successful, otherwise the
+    *   original text contents.
+    */
+  def format(file: Path, code: String): String
+
+  /** Format a single file with the given configuration.
+    *
+    * @param file
+    *   relative or absolute path to the file being formatted. Used only for the
+    *   path name, the file does not have to exist on disk.
+    * @param code
+    *   the text contents to format.
+    * @return
+    *   the formatted contents if formatting was successful, otherwise an error.
+    */
+  def formatOrError(file: Path, code: String): ScalafmtResult
+
+  /** Whether the path matches the 'project.{excludeFilters,includeFilters}'
+    * setting.
+    * @param file
+    *   path to match
+    * @return
+    *   true if the path matched the filters
+    */
+  def matchesProjectFilters(file: Path): Boolean;
+
+  /** Whether this configuration intends to limit files to those managed by git.
+    */
+  def isGitOnly: Boolean
+
+}

scalafmt-interfaces/native/src/main/java/org/scalafmt/interfaces/ScalafmtSessionFactory.scala

@@ -0,0 +1,15 @@
+package org.scalafmt.interfaces
+
+import java.nio.file.Path
+
+trait ScalafmtSessionFactory {
+
+  /** Create a ScalafmtSession to format a batch of files using fixed
+    * configuration.
+    * @param config
+    *   location of the configuration file
+    * @return
+    *   a new session instance
+    */
+  def createSession(config: Path): ScalafmtSession
+}