Replace ErrorHandler with Errors and FormatErrors*

`ErrorHandler` complicated all error handling in wabt, since it was
callback-based. Callbacks would be useful if we ever wanted to change
behavior when an error occurred, but instead all that the handler ever
did was write the errors to stdout/stderr or to a buffer.

This change adds a new class `Error`, which contains an `ErrorLevel`, a
`Location` and an error message. It also replaces ErrorHandler with
`Errors` (a typedef for `std::vector<Error>`), and adds a couple of
functions that can format a list of `Errors` for output:
`FormatErrorsTo{String,File}`.

1 files changed, 0 insertions, 149 deletions

diff --git a/src/error-handler.h b/src/error-handler.h
deleted file mode 100644
index 45e212fd..00000000
--- a/src/error-handler.h
+++ /dev/null
@@ -1,149 +0,0 @@
-/*
- * Copyright 2017 WebAssembly Community Group participants
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef WABT_ERROR_HANDLER_H_
-#define WABT_ERROR_HANDLER_H_
-
-#include <cstdarg>
-#include <string>
-
-#include "src/color.h"
-#include "src/common.h"
-#include "src/lexer-source-line-finder.h"
-
-namespace wabt {
-
-class WastLexer;
-
-class ErrorHandler {
- public:
-  explicit ErrorHandler(Location::Type);
-  ErrorHandler(Location::Type,
-               std::unique_ptr<LexerSourceLineFinder> line_finder);
-
-  virtual ~ErrorHandler() {}
-
-  // Returns true if the error was handled.
-  virtual bool OnError(ErrorLevel,
-                       const Location&,
-                       const std::string& error,
-                       const std::string& source_line,
-                       size_t source_line_column_offset) = 0;
-
-  // Helper function for binary locations.
-  bool OnError(ErrorLevel error_level,
-               size_t offset,
-               const std::string& error) {
-    return OnError(error_level, Location(offset), error, std::string(), 0);
-  }
-
-  // Helper function for va_lists.
-  bool OnError(ErrorLevel, const Location&, const char* format, va_list args);
-
-  // OnError will be called with with source_line trimmed to this length.
-  virtual size_t source_line_max_length() const = 0;
-
-  std::string DefaultErrorMessage(ErrorLevel,
-                                  const Color&,
-                                  const Location&,
-                                  const std::string& error,
-                                  const std::string& source_line,
-                                  size_t source_line_column_offset,
-                                  int indent);
-
- protected:
-  Location::Type location_type_;
-  // TODO(binji): remove unique_ptr
-  std::unique_ptr<LexerSourceLineFinder> line_finder_;
-};
-
-class ErrorHandlerNop : public ErrorHandler {
- public:
-  ErrorHandlerNop();
-
-  bool OnError(ErrorLevel,
-               const Location&,
-               const std::string& error,
-               const std::string& source_line,
-               size_t source_line_column_offset) override {
-    return false;
-  }
-
-  size_t source_line_max_length() const override { return 80; }
-};
-
-class ErrorHandlerFile : public ErrorHandler {
- public:
-  enum class PrintHeader {
-    Never,
-    Once,
-    Always,
-  };
-
-  explicit ErrorHandlerFile(Location::Type,
-                            std::unique_ptr<LexerSourceLineFinder> = {},
-                            FILE* file = stderr,
-                            const std::string& header = std::string(),
-                            PrintHeader print_header = PrintHeader::Never,
-                            size_t source_line_max_length = 80);
-
-  bool OnError(ErrorLevel,
-               const Location&,
-               const std::string& error,
-               const std::string& source_line,
-               size_t source_line_column_offset) override;
-
-  size_t source_line_max_length() const override {
-    return source_line_max_length_;
-  }
-
- private:
-  void PrintErrorHeader();
-
-  FILE* file_;
-  std::string header_;
-  PrintHeader print_header_;
-  size_t source_line_max_length_;
-  Color color_;
-};
-
-class ErrorHandlerBuffer : public ErrorHandler {
- public:
-  explicit ErrorHandlerBuffer(Location::Type,
-                              std::unique_ptr<LexerSourceLineFinder> = {},
-                              size_t source_line_max_length = 80);
-
-  bool OnError(ErrorLevel,
-               const Location&,
-               const std::string& error,
-               const std::string& source_line,
-               size_t source_line_column_offset) override;
-
-  size_t source_line_max_length() const override {
-    return source_line_max_length_;
-  }
-
-  const std::string& buffer() const { return buffer_; }
-
- private:
-  size_t source_line_max_length_;
-  std::string buffer_;
-  Color color_;
-};
-
-}  // namespace wabt
-
-#endif  // WABT_ERROR_HANDLER_H_