libSyntax: parse float literal syntax node.

lib/Parse/ParseExpr.cpp

@@ -1398,6 +1398,8 @@ ParserResult<Expr> Parser::parseExprPostfix(Diag<> ID, bool isExprBasic) {
   case tok::floating_literal: {
     StringRef Text = copyAndStripUnderscores(Context, Tok.getText());
     SourceLoc Loc = consumeToken(tok::floating_literal);
+    SyntaxContext->addTokenSyntax(Loc);
+    SyntaxContext->makeNode(SyntaxKind::FloatLiteralExpr);
     Result = makeParserResult(new (Context) FloatLiteralExpr(Text, Loc,
                                                            /*Implicit=*/false));
     break;

lib/Syntax/SyntaxParsingContext.cpp

@@ -267,6 +267,7 @@ void SyntaxParsingContextChild::makeNode(SyntaxKind Kind) {
 
   // Create syntax nodes according to the given kind.
   switch (Kind) {
+  case SyntaxKind::FloatLiteralExpr:
   case SyntaxKind::IntegerLiteralExpr: {
     // Integer may include the signs before the digits, so check if the sign
     // exists and create.

test/Syntax/Outputs/round_trip_parse_gen.swift.withkinds

@@ -1,15 +1,19 @@
 <DeclarationStmt><UnknownDecl>// RUN: %swift-syntax-test -input-source-filename %s -parse-gen > %t
-// RUN: diff -u %t %s
+// RUN: diff -u %s %t
 // RUN: %swift-syntax-test -input-source-filename %s -parse-gen -print-node-kind > %t.withkinds
-// RUN: diff -u %t.withkinds %S/Outputs/round_trip_parse_gen.swift.withkinds
+// RUN: diff -u %S/Outputs/round_trip_parse_gen.swift.withkinds %t.withkinds
 
 class C {<UnknownDecl>
   func bar(_ a: Int) {}</UnknownDecl><UnknownDecl>
+  func bar1(_ a: Float) -> Float { return <UnknownExpr><FloatLiteralExpr>-0.6 </FloatLiteralExpr>+ <FloatLiteralExpr>0.1 </FloatLiteralExpr>- <FloatLiteralExpr>0.3 </FloatLiteralExpr></UnknownExpr>}</UnknownDecl><UnknownDecl>
   func foo() {<UnknownDecl>
     var a = /*comment*/<StringLiteralExpr>"abc"/*comment*/</StringLiteralExpr></UnknownDecl><UnknownDecl>
     var b = /*comment*/<IntegerLiteralExpr>+2/*comment*/</IntegerLiteralExpr></UnknownDecl><UnknownExpr>
     bar(<IntegerLiteralExpr>1</IntegerLiteralExpr>)</UnknownExpr><UnknownExpr>
     bar(<IntegerLiteralExpr>+10</IntegerLiteralExpr>)</UnknownExpr><UnknownExpr>
-    bar(<IntegerLiteralExpr>-10</IntegerLiteralExpr>)</UnknownExpr>
+    bar(<IntegerLiteralExpr>-10</IntegerLiteralExpr>)</UnknownExpr><UnknownExpr>
+    bar1(<FloatLiteralExpr>-1.1</FloatLiteralExpr>)</UnknownExpr><UnknownExpr>
+    bar1(<FloatLiteralExpr>1.1</FloatLiteralExpr>)</UnknownExpr><UnknownDecl>
+    var f = /*comments*/<FloatLiteralExpr>+0.1/*comments*/</FloatLiteralExpr></UnknownDecl>
   }</UnknownDecl>
 }</UnknownDecl></DeclarationStmt>

test/Syntax/round_trip_parse_gen.swift

@@ -1,15 +1,19 @@
 // RUN: %swift-syntax-test -input-source-filename %s -parse-gen > %t
-// RUN: diff -u %t %s
+// RUN: diff -u %s %t
 // RUN: %swift-syntax-test -input-source-filename %s -parse-gen -print-node-kind > %t.withkinds
-// RUN: diff -u %t.withkinds %S/Outputs/round_trip_parse_gen.swift.withkinds
+// RUN: diff -u %S/Outputs/round_trip_parse_gen.swift.withkinds %t.withkinds
 
 class C {
   func bar(_ a: Int) {}
+  func bar1(_ a: Float) -> Float { return -0.6 + 0.1 - 0.3 }
   func foo() {
     var a = /*comment*/"abc"/*comment*/
     var b = /*comment*/+2/*comment*/
     bar(1)
     bar(+10)
     bar(-10)
+    bar1(-1.1)
+    bar1(1.1)
+    var f = /*comments*/+0.1/*comments*/
   }
 }