[clang-format] Extend AllowShortBlocksOnASingleLine for else blocks

Extend AllowShortBlocksOnASingleLine for else blocks. See https://bugs.llvm.org/show_bug.cgi?id=49722 Reviewed By: HazardyKnusperkeks, owenpan, MyDeveloperDay Differential Revision: https://reviews.llvm.org/D114320
llvm · Nov 25, 2021 · 813d486 · 813d486
1 parent a712b66
commit 813d486
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Showing 2 changed files with 32 additions and 10 deletions.
diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -320,9 +320,9 @@ class LineJoiner {
     }
     // Try to merge a control statement block with left brace wrapped
     if (I[1]->First->is(tok::l_brace) &&
-        (TheLine->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for,
-                                 tok::kw_switch, tok::kw_try, tok::kw_do,
-                                 TT_ForEachMacro) ||
+        (TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
+                                 tok::kw_for, tok::kw_switch, tok::kw_try,
+                                 tok::kw_do, TT_ForEachMacro) ||
          (TheLine->First->is(tok::r_brace) && TheLine->First->Next &&
           TheLine->First->Next->isOneOf(tok::kw_else, tok::kw_catch))) &&
         Style.BraceWrapping.AfterControlStatement ==
@@ -335,7 +335,7 @@ class LineJoiner {
                  ? 1
                  : 0;
     } else if (I[1]->First->is(tok::l_brace) &&
-               TheLine->First->isOneOf(tok::kw_if, tok::kw_while,
+               TheLine->First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while,
                                        tok::kw_for)) {
       return (Style.BraceWrapping.AfterControlStatement ==
               FormatStyle::BWACS_Always)
@@ -569,7 +569,7 @@ class LineJoiner {
 
     // Check that the current line allows merging. This depends on whether we
     // are in a control flow statements as well as several style flags.
-    if (Line.First->isOneOf(tok::kw_else, tok::kw_case) ||
+    if (Line.First->is(tok::kw_case) ||
         (Line.First->Next && Line.First->Next->is(tok::kw_else)))
       return 0;
     // default: in switch statement
@@ -578,20 +578,21 @@ class LineJoiner {
       if (Tok && Tok->is(tok::colon))
         return 0;
     }
-    if (Line.First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_do, tok::kw_try,
-                            tok::kw___try, tok::kw_catch, tok::kw___finally,
-                            tok::kw_for, tok::r_brace, Keywords.kw___except)) {
+    if (Line.First->isOneOf(tok::kw_if, tok::kw_else, tok::kw_while, tok::kw_do,
+                            tok::kw_try, tok::kw___try, tok::kw_catch,
+                            tok::kw___finally, tok::kw_for, tok::r_brace,
+                            Keywords.kw___except)) {
       if (Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never)
         return 0;
       // Don't merge when we can't except the case when
       // the control statement block is empty
       if (!Style.AllowShortIfStatementsOnASingleLine &&
-          Line.startsWith(tok::kw_if) &&
+          Line.First->isOneOf(tok::kw_if, tok::kw_else) &&
           !Style.BraceWrapping.AfterControlStatement &&
           !I[1]->First->is(tok::r_brace))
         return 0;
       if (!Style.AllowShortIfStatementsOnASingleLine &&
-          Line.startsWith(tok::kw_if) &&
+          Line.First->isOneOf(tok::kw_if, tok::kw_else) &&
           Style.BraceWrapping.AfterControlStatement ==
               FormatStyle::BWACS_Always &&
           I + 2 != E && !I[2]->First->is(tok::r_brace))

diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
@@ -5407,6 +5407,27 @@ TEST_F(FormatTest, PutEmptyBlocksIntoOneLine) {
   EXPECT_EQ("void f() { }", format("void f() {}", Style));
   Style.AllowShortBlocksOnASingleLine = FormatStyle::SBS_Empty;
   EXPECT_EQ("while (true) { }", format("while (true) {}", Style));
+  Style.BreakBeforeBraces = FormatStyle::BS_Custom;
+  Style.BraceWrapping.BeforeElse = false;
+  Style.BraceWrapping.AfterControlStatement = FormatStyle::BWACS_Always;
+  verifyFormat("if (a)\n"
+               "{\n"
+               "} else if (b)\n"
+               "{\n"
+               "} else\n"
+               "{ }",
+               Style);
+  Style.BraceWrapping.AfterControlStatement = FormatStyle::BWACS_Never;
+  verifyFormat("if (a) {\n"
+               "} else if (b) {\n"
+               "} else {\n"
+               "}",
+               Style);
+  Style.BraceWrapping.BeforeElse = true;
+  verifyFormat("if (a) { }\n"
+               "else if (b) { }\n"
+               "else { }",
+               Style);
 }
 
 TEST_F(FormatTest, FormatBeginBlockEndMacros) {