Merge pull request #5497 from ethereum/langutil-SourceReferenceFormatter

Moving SourceReferenceFormatter into langutil namespace.

2 files changed, 205 insertions, 0 deletions

diff --git a/liblangutil/SourceReferenceFormatter.cpp b/liblangutil/SourceReferenceFormatter.cpp
new file mode 100644
index 00000000..58a65521
--- /dev/null
+++ b/liblangutil/SourceReferenceFormatter.cpp
@@ -0,0 +1,129 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @author Christian <c@ethdev.com>
+ * @date 2014
+ * Formatting functions for errors referencing positions and locations in the source.
+ */
+
+#include <liblangutil/SourceReferenceFormatter.h>
+#include <liblangutil/Scanner.h>
+#include <liblangutil/Exceptions.h>
+
+using namespace std;
+using namespace dev;
+using namespace langutil;
+
+void SourceReferenceFormatter::printSourceLocation(SourceLocation const* _location)
+{
+	if (!_location || !_location->sourceName)
+		return; // Nothing we can print here
+	auto const& scanner = m_scannerFromSourceName(*_location->sourceName);
+	int startLine;
+	int startColumn;
+	tie(startLine, startColumn) = scanner.translatePositionToLineColumn(_location->start);
+	int endLine;
+	int endColumn;
+	tie(endLine, endColumn) = scanner.translatePositionToLineColumn(_location->end);
+	if (startLine == endLine)
+	{
+		string line = scanner.lineAtPosition(_location->start);
+
+		int locationLength = endColumn - startColumn;
+		if (locationLength > 150)
+		{
+			line = line.substr(0, startColumn + 35) + " ... " + line.substr(endColumn - 35);
+			endColumn = startColumn + 75;
+			locationLength = 75;
+		}
+		if (line.length() > 150)
+		{
+			int len = line.length();
+			line = line.substr(max(0, startColumn - 35), min(startColumn, 35) + min(locationLength + 35, len - startColumn));
+			if (startColumn + locationLength + 35 < len)
+				line += " ...";
+			if (startColumn > 35)
+			{
+				line = " ... " + line;
+				startColumn = 40;
+			}
+			endColumn = startColumn + locationLength;
+		}
+
+		m_stream << line << endl;
+
+		for_each(
+			line.cbegin(),
+			line.cbegin() + startColumn,
+			[this](char const& ch) { m_stream << (ch == '\t' ? '\t' : ' '); }
+		);
+		m_stream << "^";
+		if (endColumn > startColumn + 2)
+			m_stream << string(endColumn - startColumn - 2, '-');
+		if (endColumn > startColumn + 1)
+			m_stream << "^";
+		m_stream << endl;
+	}
+	else
+		m_stream <<
+			scanner.lineAtPosition(_location->start) <<
+			endl <<
+			string(startColumn, ' ') <<
+			"^ (Relevant source part starts here and spans across multiple lines)." <<
+			endl;
+}
+
+void SourceReferenceFormatter::printSourceName(SourceLocation const* _location)
+{
+	if (!_location || !_location->sourceName)
+		return; // Nothing we can print here
+	auto const& scanner = m_scannerFromSourceName(*_location->sourceName);
+	int startLine;
+	int startColumn;
+	tie(startLine, startColumn) = scanner.translatePositionToLineColumn(_location->start);
+	m_stream << *_location->sourceName << ":" << (startLine + 1) << ":" << (startColumn + 1) << ": ";
+}
+
+void SourceReferenceFormatter::printExceptionInformation(
+	dev::Exception const& _exception,
+	string const& _name
+)
+{
+	SourceLocation const* location = boost::get_error_info<errinfo_sourceLocation>(_exception);
+	auto secondarylocation = boost::get_error_info<errinfo_secondarySourceLocation>(_exception);
+
+	printSourceName(location);
+
+	m_stream << _name;
+	if (string const* description = boost::get_error_info<errinfo_comment>(_exception))
+		m_stream << ": " << *description << endl;
+	else
+		m_stream << endl;
+
+	printSourceLocation(location);
+
+	if (secondarylocation && !secondarylocation->infos.empty())
+	{
+		for (auto info: secondarylocation->infos)
+		{
+			printSourceName(&info.second);
+			m_stream << info.first << endl;
+			printSourceLocation(&info.second);
+		}
+		m_stream << endl;
+	}
+}
diff --git a/liblangutil/SourceReferenceFormatter.h b/liblangutil/SourceReferenceFormatter.h
new file mode 100644
index 00000000..0ef3ca00
--- /dev/null
+++ b/liblangutil/SourceReferenceFormatter.h
@@ -0,0 +1,76 @@
+/*
+	This file is part of solidity.
+
+	solidity is free software: you can redistribute it and/or modify
+	it under the terms of the GNU General Public License as published by
+	the Free Software Foundation, either version 3 of the License, or
+	(at your option) any later version.
+
+	solidity is distributed in the hope that it will be useful,
+	but WITHOUT ANY WARRANTY; without even the implied warranty of
+	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+	GNU General Public License for more details.
+
+	You should have received a copy of the GNU General Public License
+	along with solidity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @author Christian <c@ethdev.com>
+ * @date 2014
+ * Formatting functions for errors referencing positions and locations in the source.
+ */
+
+#pragma once
+
+#include <ostream>
+#include <sstream>
+#include <functional>
+
+namespace dev
+{
+struct Exception; // forward
+}
+
+namespace langutil
+{
+struct SourceLocation;
+class Scanner;
+
+class SourceReferenceFormatter
+{
+public:
+	using ScannerFromSourceNameFun = std::function<langutil::Scanner const&(std::string const&)>;
+
+	explicit SourceReferenceFormatter(
+		std::ostream& _stream,
+		ScannerFromSourceNameFun _scannerFromSourceName
+	):
+		m_stream(_stream),
+		m_scannerFromSourceName(std::move(_scannerFromSourceName))
+	{}
+
+	/// Prints source location if it is given.
+	void printSourceLocation(langutil::SourceLocation const* _location);
+	void printExceptionInformation(dev::Exception const& _exception, std::string const& _name);
+
+	static std::string formatExceptionInformation(
+		dev::Exception const& _exception,
+		std::string const& _name,
+		ScannerFromSourceNameFun const& _scannerFromSourceName
+	)
+	{
+		std::ostringstream errorOutput;
+
+		SourceReferenceFormatter formatter(errorOutput, _scannerFromSourceName);
+		formatter.printExceptionInformation(_exception, _name);
+		return errorOutput.str();
+	}
+private:
+	/// Prints source name if location is given.
+	void printSourceName(langutil::SourceLocation const* _location);
+
+	std::ostream& m_stream;
+	ScannerFromSourceNameFun m_scannerFromSourceName;
+};
+
+}