From 4e8575578e6ae2013edec96ba26cd8def93deef8 Mon Sep 17 00:00:00 2001
From: Alexey Utkin <alexey.utkin@jetbrains.com>
Date: Fri, 18 Jan 2019 21:43:16 +0300
Subject: [PATCH] CPP-14614,CPP-15164 Recognize presence of .clang-format
 configuration

* move `ClangFormatSettings` back to `ClangFormat` plugin, clean it from static methods
* introduce new `ExternalFormatProcessor` extension point
* fix CPP-15164: Update ClangFormat plugin description
* move clangd-format procedure from `OCPostFormatProcessor` to `ClangDaemonFormatProvider`
---
 .../codeStyle/ExternalFormatProcessor.java    | 70 +++++++++++++++++++
 .../src/META-INF/LangExtensionPoints.xml      |  1 +
 2 files changed, 71 insertions(+)
 create mode 100644 platform/lang-impl/src/com/intellij/psi/codeStyle/ExternalFormatProcessor.java

diff --git a/platform/lang-impl/src/com/intellij/psi/codeStyle/ExternalFormatProcessor.java b/platform/lang-impl/src/com/intellij/psi/codeStyle/ExternalFormatProcessor.java
new file mode 100644
index 000000000000..acadd1a10a2a
--- /dev/null
+++ b/platform/lang-impl/src/com/intellij/psi/codeStyle/ExternalFormatProcessor.java
@@ -0,0 +1,70 @@
+// Copyright 2000-2019 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.intellij.psi.codeStyle;
+
+import com.intellij.openapi.extensions.ExtensionPointName;
+import com.intellij.openapi.util.TextRange;
+import com.intellij.psi.PsiFile;
+import org.jetbrains.annotations.ApiStatus;
+import org.jetbrains.annotations.NonNls;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Optional;
+
+@ApiStatus.Experimental
+public interface ExternalFormatProcessor {
+  ExtensionPointName<ExternalFormatProcessor> EP_NAME = ExtensionPointName.create("com.intellij.externalFormatProcessor");
+
+  /**
+   * @param source the source file with code
+   * @return true, if external processor selected as active (enabled) for the source file
+   */
+  boolean activeForFile(@NotNull PsiFile source);
+
+  /**
+   * Formats the range in a source file.
+   *
+   * @param source the source file with code
+   * @param range the range for formatting
+   * @return the range after formatting or the initial range, if external format procedure cannot be applied to the source
+   */
+  TextRange format(@NotNull PsiFile source, @NotNull TextRange range);
+
+  /**
+   * @return the unique id for external formatter
+   */
+  @NonNls
+  @NotNull
+  String getId();
+
+  /**
+   * @param source the source file with code
+   * @return true, if there is an active external (enabled) formatter for the source
+   */
+  static boolean useExternalFormatter(@NotNull PsiFile source) {
+    return EP_NAME.getExtensionList().stream().anyMatch(efp -> efp.activeForFile(source));
+  }
+
+  /**
+   * @param externalFormatterId the unique id for external formatter
+   * @return the external formatter with the unique id, if any
+   */
+  @NotNull
+  static Optional<ExternalFormatProcessor> findExternalFormatter(@NonNls @NotNull String externalFormatterId) {
+    return EP_NAME.getExtensionList().stream().filter(efp -> externalFormatterId.equals(efp.getId())).findFirst();
+  }
+
+  /**
+   * @param source the source file with code
+   * @param range the range for formatting
+   * @return the range after formatting or empty value, if external format procedure was not found or inactive (disabled)
+   */
+  @NotNull
+  static Optional<TextRange> formatExternally(@NotNull PsiFile source, @NotNull TextRange range) {
+    for (ExternalFormatProcessor efp : EP_NAME.getExtensionList()) {
+      if (efp.activeForFile(source)) {
+        return Optional.of(efp.format(source, range));
+      }
+    }
+    return Optional.empty();
+  }
+}
diff --git a/platform/platform-resources/src/META-INF/LangExtensionPoints.xml b/platform/platform-resources/src/META-INF/LangExtensionPoints.xml
index 07cb2f90e566..a82d6f126672 100644
--- a/platform/platform-resources/src/META-INF/LangExtensionPoints.xml
+++ b/platform/platform-resources/src/META-INF/LangExtensionPoints.xml
@@ -323,6 +323,7 @@
 
     <extensionPoint name="smartPointer.anchorProvider" interface="com.intellij.psi.impl.smartPointers.SmartPointerAnchorProvider"/>
     <extensionPoint name="elementSignatureProvider" interface="com.intellij.codeInsight.folding.impl.ElementSignatureProvider"/>
+    <extensionPoint name="externalFormatProcessor" interface="com.intellij.psi.codeStyle.ExternalFormatProcessor"/>
     <extensionPoint name="preFormatProcessor" interface="com.intellij.psi.impl.source.codeStyle.PreFormatProcessor"/>
     <extensionPoint name="postFormatProcessor" interface="com.intellij.psi.impl.source.codeStyle.PostFormatProcessor"/>
     <extensionPoint name="disabledIndentRangesProvider" interface="com.intellij.psi.impl.source.DisabledIndentRangesProvider"/>