[clang] 7894e63 - [clang-format] Ignore imports in comments for Java import sorting (#177326)

[via cfe-commits]

Author: nataliakokoromyti
Date: 2026-03-14T01:07:57-07:00
New Revision: 7894e636f31a30b303b51292c4bf53931d1e82f7

URL: https://github.com/llvm/llvm-project/commit/7894e636f31a30b303b51292c4bf53931d1e82f7
DIFF: https://github.com/llvm/llvm-project/commit/7894e636f31a30b303b51292c4bf53931d1e82f7.diff

LOG: [clang-format]  Ignore imports in comments for Java import sorting (#177326)

Java source files can contain apparent import statements inside block
comments (e.g., showing a code example). These can get mixed up with
real import statements when run through clang-format.

This patch tracks block comments (/* ... */) so that we skip lines that
are inside them.

Fixes #176771

---------

Co-authored-by: Natalia Kokoromyti <knatalia at yost-cm-01-imme.stanford.edu>
Co-authored-by: owenca <owenpiano at gmail.com>

Added: 
    

Modified: 
    clang/lib/Format/Format.cpp
    clang/unittests/Format/SortImportsTestJava.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index 47be33299eadb..b98a9086811cd 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -3825,8 +3825,10 @@ static void sortJavaImports(const FormatStyle &Style,
 
 namespace {
 
-const char JavaImportRegexPattern[] =
-    "^[\t ]*import[\t ]+(static[\t ]*)?([^\t ]*)[\t ]*;";
+constexpr StringRef
+    JavaImportRegexPattern("^import[\t ]+(static[\t ]*)?([^\t ]*)[\t ]*;");
+
+constexpr StringRef JavaPackageRegexPattern("^package[\t ]");
 
 } // anonymous namespace
 
@@ -3835,26 +3837,43 @@ tooling::Replacements sortJavaImports(const FormatStyle &Style, StringRef Code,
                                       StringRef FileName,
                                       tooling::Replacements &Replaces) {
   unsigned Prev = 0;
-  unsigned SearchFrom = 0;
+  bool HasImport = false;
   llvm::Regex ImportRegex(JavaImportRegexPattern);
+  llvm::Regex PackageRegex(JavaPackageRegexPattern);
   SmallVector<StringRef, 4> Matches;
   SmallVector<JavaImportDirective, 16> ImportsInBlock;
   SmallVector<StringRef> AssociatedCommentLines;
 
-  bool FormattingOff = false;
-
-  for (;;) {
-    auto Pos = Code.find('\n', SearchFrom);
-    StringRef Line =
-        Code.substr(Prev, (Pos != StringRef::npos ? Pos : Code.size()) - Prev);
+  for (bool FormattingOff = false;;) {
+    auto Pos = Code.find('\n', Prev);
+    auto GetLine = [&] {
+      return Code.substr(Prev,
+                         (Pos != StringRef::npos ? Pos : Code.size()) - Prev);
+    };
+    StringRef Line = GetLine();
 
     StringRef Trimmed = Line.trim();
-    if (isClangFormatOff(Trimmed))
+    if (Trimmed.empty() || PackageRegex.match(Trimmed)) {
+      // Skip empty line and package statement.
+    } else if (isClangFormatOff(Trimmed)) {
       FormattingOff = true;
-    else if (isClangFormatOn(Trimmed))
+    } else if (isClangFormatOn(Trimmed)) {
       FormattingOff = false;
-
-    if (ImportRegex.match(Line, &Matches)) {
+    } else if (Trimmed.starts_with("//")) {
+      // Associating comments within the imports with the nearest import below.
+      if (HasImport)
+        AssociatedCommentLines.push_back(Line);
+    } else if (Trimmed.starts_with("/*")) {
+      Pos = Code.find("*/", Pos + 2);
+      if (Pos != StringRef::npos)
+        Pos = Code.find('\n', Pos + 2);
+      if (HasImport) {
+        // Extend `Line` for a multiline comment to include all lines the
+        // comment spans.
+        Line = GetLine();
+        AssociatedCommentLines.push_back(Line);
+      }
+    } else if (ImportRegex.match(Trimmed, &Matches)) {
       if (FormattingOff) {
         // If at least one import line has formatting turned off, turn off
         // formatting entirely.
@@ -3867,17 +3886,18 @@ tooling::Replacements sortJavaImports(const FormatStyle &Style, StringRef Code,
         IsStatic = true;
       ImportsInBlock.push_back(
           {Identifier, Line, Prev, AssociatedCommentLines, IsStatic});
+      HasImport = true;
       AssociatedCommentLines.clear();
-    } else if (!Trimmed.empty() && !ImportsInBlock.empty()) {
-      // Associating comments within the imports with the nearest import below
-      AssociatedCommentLines.push_back(Line);
+    } else {
+      // `Trimmed` is neither empty, nor a comment or a package/import
+      // statement.
+      break;
     }
-    Prev = Pos + 1;
     if (Pos == StringRef::npos || Pos + 1 == Code.size())
       break;
-    SearchFrom = Pos + 1;
+    Prev = Pos + 1;
   }
-  if (!ImportsInBlock.empty())
+  if (HasImport)
     sortJavaImports(Style, ImportsInBlock, Ranges, FileName, Code, Replaces);
   return Replaces;
 }

diff  --git a/clang/unittests/Format/SortImportsTestJava.cpp b/clang/unittests/Format/SortImportsTestJava.cpp
index 26674c75e97b1..4e7111e7e7dff 100644
--- a/clang/unittests/Format/SortImportsTestJava.cpp
+++ b/clang/unittests/Format/SortImportsTestJava.cpp
@@ -349,6 +349,37 @@ TEST_F(SortImportsTestJava, NoReplacementsForValidImportsWindows) {
       sortIncludes(FmtStyle, Code, GetCodeRange(Code), "input.java").empty());
 }
 
+TEST_F(SortImportsTestJava, DoNotSortImportsInBlockComment) {
+  constexpr StringRef Code("/* import org.d;\n"
+                           "import org.c;\n"
+                           "import org.b; */\n"
+                           "import org.a;");
+  EXPECT_EQ(Code, sort(Code));
+}
+
+TEST_F(SortImportsTestJava, StopAtClassDeclaration) {
+  constexpr StringRef Code("import org.a;\n"
+                           "\n"
+                           "class Foo {\n"
+                           "  String code = \"\"\"\n"
+                           "      import org.c;\n"
+                           "      import org.b;\n"
+                           "  \"\"\";\n"
+                           "}");
+  EXPECT_EQ(Code, sort(Code));
+}
+
+TEST_F(SortImportsTestJava, SortImportsAfterPackageStatement) {
+  EXPECT_EQ("package org.a;\n"
+            "\n"
+            "import org.a;\n"
+            "import org.b;",
+            sort("package org.a;\n"
+                 "\n"
+                 "import org.b;\n"
+                 "import org.a;"));
+}
+
 } // end namespace
 } // end namespace format
 } // end namespace clang