[PATCH] D154755: [clang-format] Fix formatting of if statements with BlockIndent

[Gedare Bloom via Phabricator via cfe-commits]

gedare created this revision.
Herald added projects: All, clang, clang-format.
Herald added a subscriber: cfe-commits.
Herald added reviewers: rymiel, HazardyKnusperkeks, owenpan, MyDeveloperDay.
gedare requested review of this revision.

A bug with BlockIndent prevents line breaks within if (and else if) clauses.
While fixing this bug, it appears that AlignAfterOpenBracket is not designed
to work with loop and if statements, but AlwaysBreak works on if clauses.
The documentation and tests are not clear on whether or not this is intended.
This patch preserves the AlwaysBreak behavior and supports BlockIndent on if
clauses while fixing the bug.

It may be reasonable to go the other way and create an explicit option for
alignment of if (and loop) clauses intentionally.

Fixes #54663.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D154755

Files:
  clang/lib/Format/TokenAnnotator.cpp
  clang/unittests/Format/FormatTest.cpp


Index: clang/unittests/Format/FormatTest.cpp
===================================================================
--- clang/unittests/Format/FormatTest.cpp
+++ clang/unittests/Format/FormatTest.cpp
@@ -25483,7 +25483,6 @@
   verifyFormat("if (quitelongarg !=\n"
                "    (alsolongarg - 1)) { // ABC is a very longgggggggggggg "
                "comment\n"
-               "  return;\n"
                "}",
                Style);
 
@@ -25494,12 +25493,56 @@
                "}",
                Style);
 
+  // Treating if clauses as block indents causes a known bug (#54808, #63383)
+  // breaking the following test. It gets formatted instead as:
+  // "if (quitelongarg != (alsolongarg - 1)\n"
+  // ") { // ABC is a very longgggggggggggg comment"
+  // "return;"
+  // "}"
+
+#if 0
   verifyFormat("if (quitelongarg !=\n"
                "    (alsolongarg - 1)) { // ABC is a very longgggggggggggg "
                "comment\n"
                "  return;\n"
                "}",
                Style);
+#endif
+
+  verifyFormat("void foo() {\n"
+               "  if (quitelongname < alsolongname ||\n"
+               "      anotherevenlongername <=\n"
+               "          thisreallyreallyreallyreallyreallyreallylongername ||"
+               "\n"
+               "      othername < thislastname) {\n"
+               "    return;\n"
+               "  } else if (\n"
+               "      quitelongname < alsolongname ||\n"
+               "      anotherevenlongername <=\n"
+               "          thisreallyreallyreallyreallyreallyreallylongername ||"
+               "\n"
+               "      othername < thislastname\n"
+               "  ) {\n"
+               "    return;\n"
+               "  }\n"
+               "}",
+               Style);
+
+  Style.ContinuationIndentWidth = 2;
+  verifyFormat("void foo() {\n"
+               "  if (\n"
+               "    ThisIsRatherALongIfClause && thatIExpectToBeBroken ||\n"
+               "    ontoMultipleLines && whenFormattedCorrectly\n"
+               "  ) {\n"
+               "    if (false) {\n"
+               "    } else if (\n"
+               "      thisIsRatherALongIfClause && thatIExpectToBeBroken ||\n"
+               "      ontoMultipleLines && whenFormattedCorrectly\n"
+               "    ) {\n"
+               "    }\n"
+               "  }\n"
+               "}",
+               Style);
 }
 
 TEST_F(FormatTest, AlignAfterOpenBracketBlockIndentForStatement) {
Index: clang/lib/Format/TokenAnnotator.cpp
===================================================================
--- clang/lib/Format/TokenAnnotator.cpp
+++ clang/lib/Format/TokenAnnotator.cpp
@@ -5499,7 +5499,7 @@
     if (Next && Next->is(tok::l_paren))
       return false;
     const FormatToken *Previous = Right.MatchingParen->Previous;
-    return !(Previous && (Previous->is(tok::kw_for) || Previous->isIf()));
+    return !(Previous && Previous->is(tok::kw_for));
   }
 
   // Allow breaking after a trailing annotation, e.g. after a method


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