Don’t break before nested block param when prior param is not a block

[segiddins]

Summary

Add ScopedTrace to verify methods in FormatTestObjC
Add tests from D17700

[kastiglione]

The purpose and the tests LGTM! Hopefully someone will weigh in on the implementation in ContinuationIndenter.cpp.

clang/lib/Format/ContinuationIndenter.cpp

if (BreakConstructorInitializersToken.is(TT_CtorInitializerColon) &&
        Style.ColumnLimit != 0))
     return true;
 
   if (Current.is(TT_ObjCMethodExpr) && !Previous.is(TT_SelectorName) &&
       State.Line->startsWith(TT_ObjCMethodSpecifier))
     return true;
   if (Current.is(TT_SelectorName) && !Previous.is(tok::at) &&
       State.Stack.back().ObjCSelectorNameFound &&
-      State.Stack.back().BreakBeforeParameter)
+      State.Stack.back().BreakBeforeParameter &&
+      (Style.ObjCBreakBeforeNestedBlockParam ||
+       !Current.startsSequence(TT_SelectorName, tok::colon, tok::caret)))
     return true;
 
   unsigned NewLineColumn = getNewLineColumn(State);
   if (Current.isMemberAccess() && Style.ColumnLimit != 0 &&
       State.Column + getLengthToNextOperator(Current) > Style.ColumnLimit &&
       (State.Column > NewLineColumn ||
        Current.NestingLevel < State.StartOfLineLevel))
     return true;

clang/unittests/Format/FormatTestObjC.cpp

 
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "gtest/gtest.h"
 
 #define DEBUG_TYPE "format-test"
 
 using clang::tooling::ReplacementTest;
+using testing::internal::ScopedTrace;
 
 namespace clang {
 namespace format {
 namespace {
 
 class FormatTestObjC : public ::testing::Test {
 protected:
   FormatTestObjC() {
if (CheckComplete != SC_DoNotCheck) {
           << Code << "\n\n";
     }
     auto Result = applyAllReplacements(Code, Replaces);
     EXPECT_TRUE(static_cast<bool>(Result));
     LLVM_DEBUG(llvm::errs() << "\n" << *Result << "\n\n");
     return *Result;
   }
 
-  void verifyFormat(StringRef Code) {
+  void _verifyFormat(const char *File, int Line, StringRef Code) {
+    ScopedTrace t(File, Line, ::testing::Message() << Code.str());
     EXPECT_EQ(Code.str(), format(Code)) << "Expected code is not stable";
     EXPECT_EQ(Code.str(), format(test::messUp(Code)));
   }
 
-  void verifyIncompleteFormat(StringRef Code) {
+  void _verifyIncompleteFormat(const char *File, int Line, StringRef Code) {
+    ScopedTrace t(File, Line, ::testing::Message() << Code.str());
     EXPECT_EQ(Code.str(), format(test::messUp(Code), SC_ExpectIncomplete));
   }
 
   FormatStyle Style;
 };
 
+#define verifyIncompleteFormat(...)                                            \
+  _verifyIncompleteFormat(__FILE__, __LINE__, __VA_ARGS__)
+#define verifyFormat(...) _verifyFormat(__FILE__, __LINE__, __VA_ARGS__)
+
 TEST(FormatTestObjCStyle, DetectsObjCInHeaders) {
   auto Style = getStyle("LLVM", "a.h", "none",
                         "@interface\n"
                         "- (id)init;");
   ASSERT_TRUE((bool)Style);
   EXPECT_EQ(FormatStyle::LK_ObjC, Style->Language);
 
   Style = getStyle("LLVM", "a.h", "none",
verifyFormat("[self.test1 t:self w:self callback:^(typeof(self) self, "
                "} z:self]");
 
   Style.ColumnLimit = 80;
   verifyFormat(
       "[self.test_method a:self b:self\n"
       "           callback:^(typeof(self) self, NSNumber *u, NSNumber *v) {\n"
       "             u = v;\n"
       "           }]");
+
+  verifyFormat("[self block:^(void) {\n"
+               "  doStuff();\n"
+               "} completionHandler:^(void) {\n"
+               "  doStuff();\n"
+               "  [self block:^(void) {\n"
+               "    doStuff();\n"
+               "  } completionHandler:^(void) {\n"
+               "    doStuff();\n"
+               "  }];\n"
+               "}];");
+
+  Style.ColumnLimit = 0;
+  verifyFormat("[[SessionService sharedService] "
+               "loadWindowWithCompletionBlock:^(SessionWindow *window) {\n"
+               "  if (window) {\n"
+               "    [self windowDidLoad:window];\n"
+               "  } else {\n"
+               "    [self errorLoadingWindow];\n"
+               "  }\n"
+               "}];");
+  verifyFormat("[controller test:^{\n"
+               "  doStuff();\n"
+               "} withTimeout:5 completionHandler:^{\n"
+               "  doStuff();\n"
+               "}];");
+  verifyFormat(
+      "[self setupTextFieldSignals:@[\n"
+      "  self.documentWidthField,\n"
+      "  self.documentHeightField,\n"
+      "] solver:^(NSTextField *textField) {\n"
+      "  return [self.representedObject solveEquationForTextField:textField];\n"
+      "}];");
 }
 
 TEST_F(FormatTestObjC, IfNotUnlikely) {
   Style = getGoogleStyle(FormatStyle::LK_ObjC);
 
   verifyFormat("if (argc < 5) [obj func:arg];");
   verifyFormat("if (argc < 5) [[obj1 method1:arg1] method2:arg2];");
   verifyFormat("if (argc < 5) [[foo bar] baz:i[0]];");