extend python-copyright as a plugin

python/python-copyright/intellij.python.copyright.iml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+      <sourceFolder url="file://$MODULE_DIR$/resources" type="java-resource" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+    <orderEntry type="module" module-name="intellij.copyright" />
+    <orderEntry type="library" name="KotlinJavaRuntime" level="project" />
+    <orderEntry type="module" module-name="intellij.platform.core" />
+    <orderEntry type="module" module-name="intellij.python.community.impl" />
+  </component>
+</module>

python/python-copyright/resources/META-INF/plugin.xml

@@ -0,0 +1,12 @@
+<idea-plugin xmlns:xi="http://www.w3.org/2001/XInclude">
+  <name>Python Copyright</name>
+  <id>org.jetbrains.plugins.python-copyright</id>
+  <version>VERSION</version>
+  <vendor>JetBrains</vendor>
+
+  <depends>com.intellij.modules.python</depends>
+  <depends>com.intellij.copyright</depends>
+
+  <xi:include href="/META-INF/python-terminal-plugin.xml" xpointer="xpointer(/idea-plugin/*)"/>
+
+</idea-plugin>

python/python-copyright/resources/META-INF/python-copyright-plugin.xml

@@ -0,0 +1,5 @@
+<idea-plugin>
+  <extensions defaultExtensionNs="com.intellij.copyright">
+    <updater filetype="Python" implementationClass="com.jetbrains.python.copyright.PyUpdateCopyrightsProvider"/>
+  </extensions>
+</idea-plugin>

python/python-copyright/src/com.jetbrains.python.copyright/PyCopyright.kt

@@ -0,0 +1,83 @@
+// Copyright 2000-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.jetbrains.python.copyright
+
+import com.intellij.openapi.fileTypes.FileType
+import com.intellij.openapi.module.Module
+import com.intellij.openapi.project.Project
+import com.intellij.openapi.vfs.VirtualFile
+import com.intellij.psi.PsiComment
+import com.intellij.psi.PsiElement
+import com.intellij.psi.util.PsiTreeUtil
+import com.jetbrains.python.psi.PyFile
+import com.maddyhome.idea.copyright.CopyrightProfile
+import com.maddyhome.idea.copyright.options.LanguageOptions
+import com.maddyhome.idea.copyright.psi.UpdateCopyright
+import com.maddyhome.idea.copyright.psi.UpdateCopyrightsProvider
+import com.maddyhome.idea.copyright.psi.UpdatePsiFileCopyright
+import java.util.function.Predicate
+import java.util.regex.Pattern
+
+class PyUpdateCopyrightsProvider : UpdateCopyrightsProvider() {
+  override fun createInstance(project: Project,
+                              module: Module?,
+                              file: VirtualFile,
+                              base: FileType?,
+                              options: CopyrightProfile?): UpdateCopyright = PyUpdateFileCopyright(project, module, file, options)
+
+  override fun getDefaultOptions(): LanguageOptions {
+    val options = super.getDefaultOptions()
+    options.block = false
+    options.fileTypeOverride = LanguageOptions.USE_TEXT
+    return options
+  }
+}
+
+
+class PyUpdateFileCopyright(project: Project, module: Module?, root: VirtualFile, options: CopyrightProfile?) : UpdatePsiFileCopyright(
+  project, module, root, options) {
+
+  override fun accept() = file is PyFile
+
+  override fun scanFile() {
+    val f = file as PyFile
+
+    val first = if (f.firstChild != null) first(f) else f
+
+    for (block in arrayOf(f.importBlock, f.topLevelClasses, f.topLevelAttributes, f.topLevelFunctions)) {
+      if (block.size > 0) {
+        checkComments(first, block.first(), true)
+        return
+      }
+    }
+
+    checkComments(first, f, true)
+  }
+}
+
+private fun first(file: PyFile): PsiElement = coding(shebang(file.firstChild))
+
+private fun isShebangComment(element: PsiElement) = element is PsiComment && element.text.startsWith("#!")
+
+private fun shebang(element: PsiElement) = if (isShebangComment(element)) {
+  skipWhitespaceForwardNotNull(element.nextSibling)
+}
+else {
+  element
+}
+
+private fun skipWhitespaceForwardNotNull(e: PsiElement): PsiElement {
+  return PsiTreeUtil.skipWhitespacesForward(e) ?: e
+}
+
+private val ENCODING_PATTERN: Predicate<String> = Pattern.compile("^[ \\t\\f]*#.*?coding[:=][ \\t]*([-_.a-zA-Z0-9]+)").asPredicate()
+
+
+private fun isEncodingComment(element: PsiElement) = element is PsiComment && ENCODING_PATTERN.test(element.text)
+
+private fun coding(element: PsiElement) = if (isEncodingComment(element)) {
+  skipWhitespaceForwardNotNull(element.nextSibling)
+}
+else {
+  element
+}
+