From e3279d8af89c9b5e99e6bca206cb5ce6ef5b0291 Mon Sep 17 00:00:00 2001
From: Alex Beregszaszi <alex@rtfs.hu>
Date: Tue, 17 Apr 2018 13:28:47 +0100
Subject: [PATCH] Display nicer error messages in the parser (display tokens
 and not internal names)

---
 Changelog.md                       |  1 +
 libsolidity/parsing/ParserBase.cpp | 22 +++++++++++-----------
 2 files changed, 12 insertions(+), 11 deletions(-)

diff --git a/Changelog.md b/Changelog.md
index 817365b9d..737a11f1b 100644
--- a/Changelog.md
+++ b/Changelog.md
@@ -4,6 +4,7 @@ Features:
  * Build System: Update internal dependency of jsoncpp to 1.8.4, which introduces more strictness and reduces memory usage.
  * Code Generator: Use native shift instructions on target Constantinople.
  * Optimizer: Remove unnecessary masking of the result of known short instructions (``ADDRESS``, ``CALLER``, ``ORIGIN`` and ``COINBASE``).
+ * Parser: Display nicer error messages by showing the actual tokens and not internal names.
  * Type Checker: Deprecate the ``years`` unit denomination and raise a warning for it (or an error as experimental 0.5.0 feature).
  * Type Checker: Make literals (without explicit type casting) an error for tight packing as experimental 0.5.0 feature.
 
diff --git a/libsolidity/parsing/ParserBase.cpp b/libsolidity/parsing/ParserBase.cpp
index 617a17799..1dd3bdd2e 100644
--- a/libsolidity/parsing/ParserBase.cpp
+++ b/libsolidity/parsing/ParserBase.cpp
@@ -71,10 +71,10 @@ void ParserBase::expectToken(Token::Value _value, bool _advance)
 		if (Token::isReservedKeyword(tok))
 		{
 			fatalParserError(
-				string("Expected token ") +
-				string(Token::name(_value)) +
-				string(" got reserved keyword '") +
-				string(Token::name(tok)) +
+				string("Expected '") +
+				string(Token::toString(_value)) +
+				string("' but got reserved keyword '") +
+				string(Token::toString(tok)) +
 				string("'")
 			);
 		}
@@ -82,19 +82,19 @@ void ParserBase::expectToken(Token::Value _value, bool _advance)
 		{
 			ElementaryTypeNameToken elemTypeName = m_scanner->currentElementaryTypeNameToken();
 			fatalParserError(
-				string("Expected token ") +
-				string(Token::name(_value)) +
-				string(" got '") +
+				string("Expected '") +
+				string(Token::toString(_value)) +
+				string("' but got '") +
 				elemTypeName.toString() +
 				string("'")
 			);
 		}
 		else
 			fatalParserError(
-				string("Expected token ") +
-				string(Token::name(_value)) +
-				string(" got '") +
-				string(Token::name(m_scanner->currentToken())) +
+				string("Expected '") +
+				string(Token::toString(_value)) +
+				string("' but got '") +
+				string(Token::toString(m_scanner->currentToken())) +
 				string("'")
 			);
 	}