[clang-format] Add ability to wrap braces after multi-line control statements
Summary:
Change the BraceWrappingFlags' AfterControlStatement from a bool to an enum with three values:
* "Never": This is the default, and does not do any brace wrapping after control statements.
* "MultiLine": This only wraps braces after multi-line control statements (this really only happens when a ColumnLimit is specified).
* "Always": This always wraps braces after control statements.
The first and last options are backwards-compatible with "false" and "true", respectively.
The new "MultiLine" option is useful for when a wrapped control statement's indentation matches the subsequent block's indentation. It makes it easier to see at a glance where the control statement ends and where the block's code begins. For example:
```
if (
foo
&& bar )
{
baz();
}
```
vs.
```
if (
foo
&& bar ) {
baz();
}
```
Short control statements (1 line) do not wrap the brace to the next line, e.g.
```
if (foo) {
bar();
} else {
baz();
}
```
Reviewers: sammccall, owenpan, reuk, MyDeveloperDay, klimek
Reviewed By: MyDeveloperDay
Subscribers: MyDeveloperDay, cfe-commits
Patch By: mitchell-stellar
Tags: #clang-format, #clang, #clang-tools-extra
Differential Revision: https://reviews.llvm.org/D68296
llvm-svn: 373647
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
index dd561cc..5b26778 100644
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -182,6 +182,20 @@
};
template <>
+struct ScalarEnumerationTraits<
+ FormatStyle::BraceWrappingAfterControlStatementStyle> {
+ static void
+ enumeration(IO &IO,
+ FormatStyle::BraceWrappingAfterControlStatementStyle &Value) {
+ IO.enumCase(Value, "false", FormatStyle::BWACS_Never);
+ IO.enumCase(Value, "true", FormatStyle::BWACS_Always);
+ IO.enumCase(Value, "Never", FormatStyle::BWACS_Never);
+ IO.enumCase(Value, "MultiLine", FormatStyle::BWACS_MultiLine);
+ IO.enumCase(Value, "Always", FormatStyle::BWACS_Always);
+ }
+};
+
+template <>
struct ScalarEnumerationTraits<FormatStyle::BreakConstructorInitializersStyle> {
static void
enumeration(IO &IO, FormatStyle::BreakConstructorInitializersStyle &Value) {
@@ -629,9 +643,12 @@
if (Style.BreakBeforeBraces == FormatStyle::BS_Custom)
return Style;
FormatStyle Expanded = Style;
- Expanded.BraceWrapping = {false, false, false, false, false, false,
- false, false, false, false, false, false,
- false, true, true, true};
+ Expanded.BraceWrapping = {false, false, FormatStyle::BWACS_Never,
+ false, false, false,
+ false, false, false,
+ false, false, false,
+ false, true, true,
+ true};
switch (Style.BreakBeforeBraces) {
case FormatStyle::BS_Linux:
Expanded.BraceWrapping.AfterClass = true;
@@ -656,7 +673,7 @@
case FormatStyle::BS_Allman:
Expanded.BraceWrapping.AfterCaseLabel = true;
Expanded.BraceWrapping.AfterClass = true;
- Expanded.BraceWrapping.AfterControlStatement = true;
+ Expanded.BraceWrapping.AfterControlStatement = FormatStyle::BWACS_Always;
Expanded.BraceWrapping.AfterEnum = true;
Expanded.BraceWrapping.AfterFunction = true;
Expanded.BraceWrapping.AfterNamespace = true;
@@ -670,7 +687,7 @@
case FormatStyle::BS_Whitesmiths:
Expanded.BraceWrapping.AfterCaseLabel = true;
Expanded.BraceWrapping.AfterClass = true;
- Expanded.BraceWrapping.AfterControlStatement = true;
+ Expanded.BraceWrapping.AfterControlStatement = FormatStyle::BWACS_Always;
Expanded.BraceWrapping.AfterEnum = true;
Expanded.BraceWrapping.AfterFunction = true;
Expanded.BraceWrapping.AfterNamespace = true;
@@ -681,8 +698,12 @@
Expanded.BraceWrapping.BeforeElse = true;
break;
case FormatStyle::BS_GNU:
- Expanded.BraceWrapping = {true, true, true, true, true, true, true, true,
- true, true, true, true, true, true, true, true};
+ Expanded.BraceWrapping = {true, true, FormatStyle::BWACS_Always,
+ true, true, true,
+ true, true, true,
+ true, true, true,
+ true, true, true,
+ true};
break;
case FormatStyle::BS_WebKit:
Expanded.BraceWrapping.AfterFunction = true;
@@ -722,9 +743,12 @@
LLVMStyle.BreakBeforeBinaryOperators = FormatStyle::BOS_None;
LLVMStyle.BreakBeforeTernaryOperators = true;
LLVMStyle.BreakBeforeBraces = FormatStyle::BS_Attach;
- LLVMStyle.BraceWrapping = {false, false, false, false, false, false,
- false, false, false, false, false, false,
- false, true, true, true};
+ LLVMStyle.BraceWrapping = {false, false, FormatStyle::BWACS_Never,
+ false, false, false,
+ false, false, false,
+ false, false, false,
+ false, true, true,
+ true};
LLVMStyle.BreakAfterJavaFieldAnnotations = false;
LLVMStyle.BreakConstructorInitializers = FormatStyle::BCIS_BeforeColon;
LLVMStyle.BreakInheritanceList = FormatStyle::BILS_BeforeColon;
@@ -1067,7 +1091,7 @@
Style.UseTab = FormatStyle::UT_Never;
Style.BreakBeforeBraces = FormatStyle::BS_Custom;
Style.BraceWrapping.AfterClass = true;
- Style.BraceWrapping.AfterControlStatement = true;
+ Style.BraceWrapping.AfterControlStatement = FormatStyle::BWACS_Always;
Style.BraceWrapping.AfterEnum = true;
Style.BraceWrapping.AfterFunction = true;
Style.BraceWrapping.AfterNamespace = true;
diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
index df30f7d..8b8d357 100644
--- a/clang/lib/Format/UnwrappedLineFormatter.cpp
+++ b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -306,8 +306,24 @@
}
// 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)) {
- return Style.BraceWrapping.AfterControlStatement
+ (TheLine->First->isOneOf(tok::kw_if, tok::kw_while, tok::kw_for,
+ tok::kw_switch, tok::kw_try, tok::kw_do) ||
+ (TheLine->First->is(tok::r_brace) && TheLine->First->Next &&
+ TheLine->First->Next->isOneOf(tok::kw_else, tok::kw_catch))) &&
+ Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_MultiLine) {
+ // If possible, merge the next line's wrapped left brace with the current
+ // line. Otherwise, leave it on the next line, as this is a multi-line
+ // control statement.
+ return (Style.ColumnLimit == 0 ||
+ TheLine->Last->TotalLength <= Style.ColumnLimit)
+ ? 1
+ : 0;
+ } else if (I[1]->First->is(tok::l_brace) &&
+ TheLine->First->isOneOf(tok::kw_if, tok::kw_while,
+ tok::kw_for)) {
+ return (Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_Always)
? tryMergeSimpleBlock(I, E, Limit)
: 0;
}
@@ -410,7 +426,8 @@
SmallVectorImpl<AnnotatedLine *>::const_iterator E, unsigned Limit) {
if (Limit == 0)
return 0;
- if (Style.BraceWrapping.AfterControlStatement &&
+ if (Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_Always &&
I[1]->First->is(tok::l_brace) &&
Style.AllowShortBlocksOnASingleLine == FormatStyle::SBS_Never)
return 0;
@@ -523,8 +540,9 @@
return 0;
if (!Style.AllowShortIfStatementsOnASingleLine &&
Line.startsWith(tok::kw_if) &&
- Style.BraceWrapping.AfterControlStatement && I + 2 != E &&
- !I[2]->First->is(tok::r_brace))
+ Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_Always &&
+ I + 2 != E && !I[2]->First->is(tok::r_brace))
return 0;
if (!Style.AllowShortLoopsOnASingleLine &&
Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for) &&
@@ -533,8 +551,9 @@
return 0;
if (!Style.AllowShortLoopsOnASingleLine &&
Line.First->isOneOf(tok::kw_while, tok::kw_do, tok::kw_for) &&
- Style.BraceWrapping.AfterControlStatement && I + 2 != E &&
- !I[2]->First->is(tok::r_brace))
+ Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_Always &&
+ I + 2 != E && !I[2]->First->is(tok::r_brace))
return 0;
// FIXME: Consider an option to allow short exception handling clauses on
// a single line.
@@ -597,6 +616,17 @@
if (Tok->Next && Tok->Next->is(tok::kw_else))
return 0;
+ // Don't merge a trailing multi-line control statement block like:
+ // } else if (foo &&
+ // bar)
+ // { <-- current Line
+ // baz();
+ // }
+ if (Line.First == Line.Last &&
+ Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_MultiLine)
+ return 0;
+
return 2;
}
} else if (I[1]->First->is(tok::l_brace)) {
diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
index 8fd0e94..bbe0560 100644
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -1167,7 +1167,8 @@
case tok::objc_autoreleasepool:
nextToken();
if (FormatTok->Tok.is(tok::l_brace)) {
- if (Style.BraceWrapping.AfterControlStatement)
+ if (Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_Always)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
}
@@ -1179,7 +1180,8 @@
// Skip synchronization object
parseParens();
if (FormatTok->Tok.is(tok::l_brace)) {
- if (Style.BraceWrapping.AfterControlStatement)
+ if (Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_Always)
addUnwrappedLine();
parseBlock(/*MustBeDeclaration=*/false);
}
@@ -1989,7 +1991,8 @@
Style.BraceWrapping.IndentBraces);
parseBlock(/*MustBeDeclaration=*/false);
if (FormatTok->Tok.is(tok::kw_break)) {
- if (Style.BraceWrapping.AfterControlStatement)
+ if (Style.BraceWrapping.AfterControlStatement ==
+ FormatStyle::BWACS_Always)
addUnwrappedLine();
parseStructuralElement();
}