Try to keep function-typed parameters parameter lists with the parame…

…ter name.

I can't repro the original issue in google#58, so other nested list changes likely took
care of that, but this addresses the other comments on that bug.

Fixes google#58.

BUG=dart-lang/dart_style#58
R=kevmoo@google.com

Review URL: https://chromiumcodereview.appspot.com//830543002

lib/src/source_visitor.dart

@@ -706,8 +706,12 @@ class SourceVisitor implements AstVisitor {
 
   visitFunctionTypedFormalParameter(FunctionTypedFormalParameter node) {
     visitNode(node.returnType, after: space);
+
+    // Try to keep the function's parameters with its name.
+    _writer.startSpan();
     visit(node.identifier);
     visit(node.parameters);
+    _writer.endSpan();
   }
 
   visitHideCombinator(HideCombinator node) {

test/regression/58.unit

@@ -0,0 +1,7 @@
+>>>
+bool doStuff(String firstArgX, {String secondArg, String arg3foo, Map<String,
+    String> anotherArg, bool yetAnotherArg: false, bool tooManyArgs: true}) {}
+<<<
+bool doStuff(String firstArgX, {String secondArg, String arg3foo,
+    Map<String, String> anotherArg, bool yetAnotherArg: false,
+    bool tooManyArgs: true}) {}

test/splitting/parameters.stmt

@@ -57,4 +57,19 @@ reallyLongMethod(parameter,
 reallyLongMethod(parameter, {foo, bar}) {}
 <<<
 reallyLongMethod(parameter,
-    {foo, bar}) {}
+    {foo, bar}) {}
+>>> avoid splitting in function type parameters
+bool doStuff(parameter1, void printFn(param1, param2)) {}
+<<<
+bool doStuff(parameter1,
+    void printFn(param1, param2)) {}
+>>>
+doStuff(param1, void printFn(param1, param2)) {}
+<<<
+doStuff(param1,
+    void printFn(param1, param2)) {}
+>>> allow splitting in function type parameters
+doStuff(callback(parameter1, parameter2, parameter3, parameter4)) {}
+<<<
+doStuff(callback(parameter1, parameter2,
+    parameter3, parameter4)) {}