[clang] [clang-format] Add space in Verilog tagged unions (PR #71354)

[via cfe-commits]

https://github.com/sstwcw created https://github.com/llvm/llvm-project/pull/71354

In a tagged union expression, there should be a space between the field name and the data.  Previously, the tag could be recognized as part of a dotted identifier or a struct literal, and the space would be omitted.

>From 758fc8c9240452b90c3df2781429ae07699ef577 Mon Sep 17 00:00:00 2001
From: sstwcw <su3e8a96kzlver at posteo.net>
Date: Mon, 6 Nov 2023 03:26:02 +0000
Subject: [PATCH] [clang-format] Add space in Verilog tagged unions

In a tagged union expression, there should be a space between the field
name and the data.  Previously, the tag could be recognized as part of a
dotted identifier or a struct literal, and the space would be omitted.
---
 clang/lib/Format/TokenAnnotator.cpp          |  9 ++++++++-
 clang/unittests/Format/FormatTestVerilog.cpp | 14 ++++++++++++--
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
index 729e7e370bf62ea..263125d5711a95b 100644
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -4694,8 +4694,15 @@ bool TokenAnnotator::spaceRequiredBefore(const AnnotatedLine &Line,
         Left.isOneOf(TT_VerilogDimensionedTypeName, Keywords.kw_function)) {
       return true;
     }
+    // In a tagged union expression, there should be a space after the tag.
+    if (Right.isOneOf(tok::period, Keywords.kw_apostrophe) &&
+        Keywords.isVerilogIdentifier(Left) && Left.getPreviousNonComment() &&
+        Left.getPreviousNonComment()->is(Keywords.kw_tagged)) {
+      return true;
+    }
     // Don't add spaces between a casting type and the quote or repetition count
-    // and the brace.
+    // and the brace.  The case of tagged union expressions is handled by the
+    // previous rule.
     if ((Right.is(Keywords.kw_apostrophe) ||
          (Right.is(BK_BracedInit) && Right.is(tok::l_brace))) &&
         !(Left.isOneOf(Keywords.kw_assign, Keywords.kw_unique) ||
diff --git a/clang/unittests/Format/FormatTestVerilog.cpp b/clang/unittests/Format/FormatTestVerilog.cpp
index 1c2692467987d9b..99d0fcca38c3993 100644
--- a/clang/unittests/Format/FormatTestVerilog.cpp
+++ b/clang/unittests/Format/FormatTestVerilog.cpp
@@ -359,6 +359,11 @@ TEST_F(FormatTestVerilog, Case) {
                "      arg);\n"
                "endcase",
                Style);
+
+  verifyFormat("case (v) matches\n"
+               "  tagged Valid .n:\n"
+               "    ;\n"
+               "endcase");
 }
 
 TEST_F(FormatTestVerilog, Coverage) {
@@ -1278,12 +1283,17 @@ TEST_F(FormatTestVerilog, StructLiteral) {
   verifyFormat("c = '{'{1, 1.0}, '{2, 2.0}};");
   verifyFormat("c = '{a: 0, b: 0.0};");
   verifyFormat("c = '{a: 0, b: 0.0, default: 0};");
+  verifyFormat("d = {int: 1, shortreal: 1.0};");
+  verifyFormat("c = '{default: 0};");
+
+  // The identifier before the quote can be either a tag or a type case.  There
+  // should be a space between the tag and the quote.
   verifyFormat("c = ab'{a: 0, b: 0.0};");
   verifyFormat("c = ab'{cd: cd'{1, 1.0}, ef: ef'{2, 2.0}};");
   verifyFormat("c = ab'{cd'{1, 1.0}, ef'{2, 2.0}};");
-  verifyFormat("d = {int: 1, shortreal: 1.0};");
   verifyFormat("d = ab'{int: 1, shortreal: 1.0};");
-  verifyFormat("c = '{default: 0};");
+  verifyFormat("x = tagged Add '{e1, 4, ed};");
+
   auto Style = getDefaultStyle();
   Style.SpacesInContainerLiterals = true;
   verifyFormat("c = '{a : 0, b : 0.0};", Style);