From 1e07da7a98f9f2641a0f34e792584027bcb9e964 Mon Sep 17 00:00:00 2001
From: Akash Yadav <itsaky01@gmail.com>
Date: Fri, 21 Jul 2023 18:43:25 +0530
Subject: [PATCH] fix(javac): add Java compiler flag to override
 -XDkeepComments flag

When the 'keepComments' flag is set, the compiler uses JavadocTokenizer for tokenizing the source code. While creating the LineMap instance, the JavadocTokenizer sets the 'expandTabs' flag to true which expands '\t' characters to spaces. This is needed while generating HTML pages for the Javadoc. However, if the tabs are expanded to spaces, then getPosition(...) and getColumnNumber(...) methods in the LineMap class return indices which cannot be directly used to insert text in the source code. This results in StringIndexOutOfBoundsException when trying to insert text in the editor (#1127, and probably #916 as well).

This commit adds the 'keepCommentsOverride' option to the compiler which is used by NBParserFactory to override the 'keepComments' flag. The CompileBatch class sets this option to 'ignore' which ignores the 'keepComments' flag so that JavadocTokenizer is not used for tokenization.
---
 .../lsp/java/compiler/CompileBatch.java       |  1 +
 .../javac/services/NBParserFactory.java       | 31 +++++++++++++++++--
 2 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/lsp/java/src/main/java/com/itsaky/androidide/lsp/java/compiler/CompileBatch.java b/lsp/java/src/main/java/com/itsaky/androidide/lsp/java/compiler/CompileBatch.java
index 061f8dd4c..d18d965d4 100644
--- a/lsp/java/src/main/java/com/itsaky/androidide/lsp/java/compiler/CompileBatch.java
+++ b/lsp/java/src/main/java/com/itsaky/androidide/lsp/java/compiler/CompileBatch.java
@@ -168,6 +168,7 @@ public class CompileBatch implements AutoCloseable {
         "-XDcompilePolicy=byfile",
         "-XD-Xprefer=source",
         "-XDide",
+        "-XDkeepCommentsOverride=ignore",
         "-XDsuppressAbortOnBadClassFile",
         "-XDshould-stop.at=GENERATE",
         "-XDdiags.formatterOptions=-source",
diff --git a/subprojects/javac-services/src/main/java/com/itsaky/androidide/javac/services/NBParserFactory.java b/subprojects/javac-services/src/main/java/com/itsaky/androidide/javac/services/NBParserFactory.java
index 004c14ada..a37883537 100644
--- a/subprojects/javac-services/src/main/java/com/itsaky/androidide/javac/services/NBParserFactory.java
+++ b/subprojects/javac-services/src/main/java/com/itsaky/androidide/javac/services/NBParserFactory.java
@@ -35,6 +35,7 @@
  */
 package com.itsaky.androidide.javac.services;
 
+import com.itsaky.androidide.utils.ILogger;
 import openjdk.tools.javac.parser.JavacParser;
 import openjdk.tools.javac.parser.Lexer;
 import openjdk.tools.javac.parser.ParserFactory;
@@ -52,6 +53,7 @@ import openjdk.tools.javac.util.Context;
 import openjdk.tools.javac.util.List;
 import openjdk.tools.javac.util.Name;
 import openjdk.tools.javac.util.Names;
+import openjdk.tools.javac.util.Options;
 import openjdk.tools.javac.util.Position;
 
 /**
@@ -59,10 +61,18 @@ import openjdk.tools.javac.util.Position;
  */
 public class NBParserFactory extends ParserFactory {
 
+  public static final String KEEP_COMMENTS_OVERRIDE = "keepCommentsOverride";
+  public static final String KEEP_COMMENTS_OVERRIDE_KEEP = "keep";
+  public static final String KEEP_COMMENTS_OVERRIDE_IGNORE = "ignore";
+
+  private static final ILogger LOG = ILogger.newInstance("NBParserFactory");
+
   protected final ScannerFactory scannerFactory;
   protected final Names names;
   protected final CancelService cancelService;
 
+  protected final String keepCommentsOverride;
+
   public static void preRegister(Context context) {
     context.put(parserFactoryKey, (Context.Factory<ParserFactory>) NBParserFactory::new);
   }
@@ -72,6 +82,8 @@ public class NBParserFactory extends ParserFactory {
     this.scannerFactory = ScannerFactory.instance(context);
     this.names = Names.instance(context);
     this.cancelService = CancelService.instance(context);
+    this.keepCommentsOverride = Options.instance(context).get(KEEP_COMMENTS_OVERRIDE);
+
   }
 
   @Override
@@ -81,9 +93,20 @@ public class NBParserFactory extends ParserFactory {
       boolean keepEndPos,
       boolean keepLineMap,
       boolean parseModuleInfo) {
-    Lexer lexer = scannerFactory.newScanner(input, keepDocComments);
+    var keepDocCommentsOverride = keepDocComments;
+    if (this.keepCommentsOverride != null) {
+      if (KEEP_COMMENTS_OVERRIDE_IGNORE.equals(this.keepCommentsOverride)) {
+        keepDocCommentsOverride = false;
+      } else if (KEEP_COMMENTS_OVERRIDE_KEEP.equals(this.keepCommentsOverride)) {
+        keepDocCommentsOverride = true;
+      }
+      LOG.debug("'keepComments' overridden to ", this.keepCommentsOverride);
+    }
+
+    Lexer lexer = scannerFactory.newScanner(input, keepDocCommentsOverride);
     return new NBJavacParser(
-        this, lexer, keepDocComments, keepLineMap, keepEndPos, parseModuleInfo, cancelService);
+        this, lexer, keepDocCommentsOverride, keepLineMap, keepEndPos, parseModuleInfo,
+        cancelService);
   }
 
   public static class NBJavacParser extends JavacParser {
@@ -201,7 +224,9 @@ public class NBParserFactory extends ParserFactory {
 
       @Override
       public void storeEnd(JCTree tree, int endpos) {
-        if (endpos >= 0) delegate.storeEnd(tree, endpos);
+        if (endpos >= 0) {
+          delegate.storeEnd(tree, endpos);
+        }
       }
 
       @Override