[SyntaxMap] Fold unary minus into numeric literals

Unlike other prefix operators, unary minus is folded into the
NumberLiteralExpr in the parser. This commit recreates this effect in
the lexer-based syntax map so that token ranges will include the leading
minus.

rdar://problem/20205885

Author: benlangmuir

lib/IDE/SyntaxModel.cpp

@@ -58,6 +58,7 @@ SyntaxModelContext::SyntaxModelContext(SourceFile &SrcFile)
                                            /*TokenizeInterpolatedString=*/true);
   std::vector<SyntaxNode> Nodes;
   SourceLoc AttrLoc;
+  SourceLoc UnaryMinusLoc;
   auto LiteralStartLoc = Optional<SourceLoc>();
   for (unsigned I = 0, E = Tokens.size(); I != E; ++I) {
     auto &Tok = Tokens[I];
@@ -119,9 +120,28 @@ SyntaxModelContext::SyntaxModelContext(SourceFile &SrcFile)
           Kind = SyntaxNodeKind::Identifier;
         break;
       case tok::dollarident: Kind = SyntaxNodeKind::DollarIdent; break;
-      case tok::integer_literal: Kind = SyntaxNodeKind::Integer; break;
-      case tok::floating_literal: Kind = SyntaxNodeKind::Floating; break;
       case tok::string_literal: Kind = SyntaxNodeKind::String; break;
+
+      case tok::integer_literal:
+        Kind = SyntaxNodeKind::Integer;
+        if (UnaryMinusLoc.isValid()) {
+          Loc = UnaryMinusLoc;
+          Length = *Length + SM.getByteDistance(UnaryMinusLoc, Tok.getLoc());
+        }
+        break;
+      case tok::floating_literal:
+        Kind = SyntaxNodeKind::Floating;
+        if (UnaryMinusLoc.isValid()) {
+          Loc = UnaryMinusLoc;
+          Length = *Length + SM.getByteDistance(UnaryMinusLoc, Tok.getLoc());
+        }
+        break;
+
+      case tok::oper_prefix:
+        if (Tok.getText() == "-")
+          UnaryMinusLoc = Loc;
+        continue;
+
       case tok::comment:
         if (Tok.getText().startswith("///") ||
             (IsPlayground && Tok.getText().startswith("//:")))
@@ -179,6 +199,8 @@ SyntaxModelContext::SyntaxModelContext(SourceFile &SrcFile)
       }
     }
 
+    UnaryMinusLoc = SourceLoc(); // Reset.
+
     assert(Loc.isValid());
     assert(Nodes.empty() || SM.isBeforeInBuffer(Nodes.back().Range.getStart(),
                                                 Loc));

test/IDE/coloring.swift

@@ -454,6 +454,17 @@ func funcTakingFor(for internalName: Int) {}
 func funcTakingIn(in internalName: Int) {}
 // CHECK: <kw>func</kw> funcTakingIn(in internalName: <type>Int</type>) {}
 
+_ = 123
+// CHECK: <int>123</int>
+_ = -123
+// CHECK: <int>-123</int>
+_ = -1
+// CHECK: <int>-1</int>
+_ = -0x123
+// CHECK: <int>-0x123</int>
+_ = -3.1e-5
+// CHECK: <float>-3.1e-5</float>
+
 "--\"\(x) --"
 // CHECK: <str>"--\"</str>\<anchor>(</anchor>x<anchor>)</anchor><str> --"</str>
 

test/SourceKit/SyntaxMapData/Inputs/syntaxmap.swift

@@ -47,3 +47,5 @@ func bar() {}
 // radar:1234567
 // mailto:thisisnotmail
 // unknownprotocol://awesomeguy.com
+
+_ = -123

test/SourceKit/SyntaxMapData/syntaxmap.swift.response

@@ -1,6 +1,6 @@
 {
   key.offset: 0,
-  key.length: 849,
+  key.length: 859,
   key.diagnostic_stage: source.diagnostic.stage.swift.parse,
   key.syntaxmap: [
     {
@@ -412,6 +412,16 @@
       key.kind: source.lang.swift.syntaxtype.comment,
       key.offset: 813,
       key.length: 36
+    },
+    {
+      key.kind: source.lang.swift.syntaxtype.keyword,
+      key.offset: 850,
+      key.length: 1
+    },
+    {
+      key.kind: source.lang.swift.syntaxtype.number,
+      key.offset: 854,
+      key.length: 4
     }
   ]
 }