clang-format: Fix bug with conflicting BreakBeforeBinaryOperations and AlignAfterOpenBracket

Fix for the formatting options combination of
BreakBeforeBinaryOperators: All, AlignAfterOpenBracket: AlwaysBreak not
handling long templates correctly. This patch allows a break after an
opening left parenthesis, TemplateOpener, or bracket when both options
are enabled.

Patch by Daphne Pfister, thank you!

Fixes llvm.org/PR30304.

llvm-svn: 294179
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
index 6cc9d19..8f531af 100644
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -6140,6 +6140,44 @@
                "};");
 }
 
+TEST_F(FormatTest, WrapsTemplateParameters) {
+  FormatStyle Style = getLLVMStyle();
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_DontAlign;
+  Style.BreakBeforeBinaryOperators = FormatStyle::BOS_None;
+  verifyFormat(
+      "template <typename... a> struct q {};\n"
+      "extern q<aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa,\n"
+      "    aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa>\n"
+      "    y;",
+      Style);
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_DontAlign;
+  Style.BreakBeforeBinaryOperators = FormatStyle::BOS_All;
+  verifyFormat(
+      "template <typename... a> struct r {};\n"
+      "extern r<aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa,\n"
+      "    aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaa>\n"
+      "    y;",
+      Style);
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_AlwaysBreak;
+  Style.BreakBeforeBinaryOperators = FormatStyle::BOS_None;
+  verifyFormat(
+      "template <typename... a> struct s {};\n"
+      "extern s<\n"
+      "    aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa,\n"
+      "    aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa>\n"
+      "    y;",
+      Style);
+  Style.AlignAfterOpenBracket = FormatStyle::BAS_AlwaysBreak;
+  Style.BreakBeforeBinaryOperators = FormatStyle::BOS_All;
+  verifyFormat(
+      "template <typename... a> struct t {};\n"
+      "extern t<\n"
+      "    aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa,\n"
+      "    aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa, aaaaaaaaaaaaaaaaaaaaaa>\n"
+      "    y;",
+      Style);
+}
+
 TEST_F(FormatTest, WrapsAtNestedNameSpecifiers) {
   verifyFormat(
       "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa::\n"