pkg/compiler/lib/src/io/source_map_builder.dart - sdk.git - Git at Google

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 library dart2js.source_map_builder;

 import '../util/uri_extras.dart' show relativize;
 import '../util/util.dart';
 import 'line_column_provider.dart';
 import 'source_information.dart' show SourceLocation;

 class SourceMapBuilder {
   /// The URI of the source map file.
   final Uri sourceMapUri;

   /// The URI of the target language file.
   final Uri targetFileUri;

   final LineColumnProvider lineColumnProvider;
   final List<SourceMapEntry> entries = new List<SourceMapEntry>();

   SourceMapBuilder(
       this.sourceMapUri, this.targetFileUri, this.lineColumnProvider);

   void addMapping(int targetOffset, SourceLocation sourceLocation) {
     entries.add(new SourceMapEntry(sourceLocation, targetOffset));
   }

   void printStringListOn(Iterable<String> strings, StringBuffer buffer) {
     bool first = true;
     buffer.write('[');
     for (String string in strings) {
       if (!first) buffer.write(',');
       buffer.write('"');
       writeJsonEscapedCharsOn(string, buffer);
       buffer.write('"');
       first = false;
     }
     buffer.write(']');
   }

   String build() {
     LineColumnMap<SourceMapEntry> lineColumnMap =
         new LineColumnMap<SourceMapEntry>();
     Map<Uri, LineColumnMap<SourceMapEntry>> sourceLocationMap =
         <Uri, LineColumnMap<SourceMapEntry>>{};
     entries.forEach((SourceMapEntry sourceMapEntry) {
       int line = lineColumnProvider.getLine(sourceMapEntry.targetOffset);
       int column =
           lineColumnProvider.getColumn(line, sourceMapEntry.targetOffset);
       lineColumnMap.add(line, column, sourceMapEntry);

       SourceLocation location = sourceMapEntry.sourceLocation;
       if (location != null) {
         if (location.sourceUri != null) {
           LineColumnMap<SourceMapEntry> sourceLineColumnMap =
               sourceLocationMap.putIfAbsent(location.sourceUri,
                   () => new LineColumnMap<SourceMapEntry>());
           sourceLineColumnMap.add(
               location.line, location.column, sourceMapEntry);
         }
       }
     });

     return _build(lineColumnMap);
   }

   String _build(LineColumnMap<SourceMapEntry> lineColumnMap) {
     IndexMap<Uri> uriMap = new IndexMap<Uri>();
     IndexMap<String> nameMap = new IndexMap<String>();

     lineColumnMap.forEachElement((SourceMapEntry entry) {
       SourceLocation sourceLocation = entry.sourceLocation;
       if (sourceLocation != null) {
         if (sourceLocation.sourceUri != null) {
           uriMap.register(sourceLocation.sourceUri);
           if (sourceLocation.sourceName != null) {
             nameMap.register(sourceLocation.sourceName);
           }
         }
       }
     });

     StringBuffer mappingsBuffer = new StringBuffer();
     writeEntries(lineColumnMap, uriMap, nameMap, mappingsBuffer);

     StringBuffer buffer = new StringBuffer();
     buffer.write('{\n');
     buffer.write('  "version": 3,\n');
     if (sourceMapUri != null && targetFileUri != null) {
       buffer.write(
           '  "file": "${relativize(sourceMapUri, targetFileUri, false)}",\n');
     }
     buffer.write('  "sourceRoot": "",\n');
     buffer.write('  "sources": ');
     Iterable<String> relativeSourceUriList = const <String>[];
     if (sourceMapUri != null) {
       relativeSourceUriList =
           uriMap.elements.map((u) => relativize(sourceMapUri, u, false));
     }
     printStringListOn(relativeSourceUriList, buffer);
     buffer.write(',\n');
     buffer.write('  "names": ');
     printStringListOn(nameMap.elements, buffer);
     buffer.write(',\n');
     buffer.write('  "mappings": "');
     buffer.write(mappingsBuffer);
     buffer.write('"\n}\n');
     return buffer.toString();
   }

   void writeEntries(LineColumnMap<SourceMapEntry> entries, IndexMap<Uri> uriMap,
       IndexMap<String> nameMap, StringBuffer output) {
     SourceLocation previousSourceLocation;
     int previousTargetLine = 0;
     DeltaEncoder targetColumnEncoder = new DeltaEncoder();
     bool firstEntryInLine = true;
     DeltaEncoder sourceUriIndexEncoder = new DeltaEncoder();
     DeltaEncoder sourceLineEncoder = new DeltaEncoder();
     DeltaEncoder sourceColumnEncoder = new DeltaEncoder();
     DeltaEncoder sourceNameIndexEncoder = new DeltaEncoder();

     entries.forEach((int targetLine, int targetColumn, SourceMapEntry entry) {
       SourceLocation sourceLocation = entry.sourceLocation;
       if (sourceLocation == previousSourceLocation) {
         return;
       }

       if (targetLine > previousTargetLine) {
         for (int i = previousTargetLine; i < targetLine; ++i) {
           output.write(';');
         }
         previousTargetLine = targetLine;
         previousSourceLocation = null;
         targetColumnEncoder.reset();
         firstEntryInLine = true;
       }

       if (!firstEntryInLine) {
         output.write(',');
       }
       firstEntryInLine = false;

       targetColumnEncoder.encode(output, targetColumn);

       if (sourceLocation == null) {
         return;
       }

       Uri sourceUri = sourceLocation.sourceUri;
       if (sourceUri != null) {
         sourceUriIndexEncoder.encode(output, uriMap[sourceUri]);
         sourceLineEncoder.encode(output, sourceLocation.line);
         sourceColumnEncoder.encode(output, sourceLocation.column);
       }

       String sourceName = sourceLocation.sourceName;
       if (sourceName != null) {
         sourceNameIndexEncoder.encode(output, nameMap[sourceName]);
       }

       previousSourceLocation = sourceLocation;
     });
   }
 }

 /// Encoder for value deltas in VLQ format.
 class DeltaEncoder {
   /// The last emitted value of the encoder.
   int _value = 0;

   /// Reset the encoder to its initial state.
   void reset() {
     _value = 0;
   }

   /// Writes the VLQ of delta between [value] and the last emitted value into
   /// [output] and updates the last emitted value of the encoder.
   void encode(StringBuffer output, int value) {
     _value = encodeVLQ(output, value, _value);
   }

   static const int VLQ_BASE_SHIFT = 5;
   static const int VLQ_BASE_MASK = (1 << 5) - 1;
   static const int VLQ_CONTINUATION_BIT = 1 << 5;
   static const int VLQ_CONTINUATION_MASK = 1 << 5;
   static const String BASE64_DIGITS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmn'
       'opqrstuvwxyz0123456789+/';

   /// Writes the VLQ of delta between [value] and [offset] into [output] and
   /// return [value].
   static int encodeVLQ(StringBuffer output, int value, int offset) {
     int delta = value - offset;
     int signBit = 0;
     if (delta < 0) {
       signBit = 1;
       delta = -delta;
     }
     delta = (delta << 1) | signBit;
     do {
       int digit = delta & VLQ_BASE_MASK;
       delta >>= VLQ_BASE_SHIFT;
       if (delta > 0) {
         digit |= VLQ_CONTINUATION_BIT;
       }
       output.write(BASE64_DIGITS[digit]);
     } while (delta > 0);
     return value;
   }
 }

 class SourceMapEntry {
   SourceLocation sourceLocation;
   int targetOffset;

   SourceMapEntry(this.sourceLocation, this.targetOffset);
 }

 /// Map from line/column pairs to lists of [T] elements.
 class LineColumnMap<T> {
   Map<int, Map<int, List<T>>> _map = <int, Map<int, List<T>>>{};

   /// Returns the list of elements associated with ([line],[column]).
   List<T> _getList(int line, int column) {
     Map<int, List<T>> lineMap = _map.putIfAbsent(line, () => <int, List<T>>{});
     return lineMap.putIfAbsent(column, () => <T>[]);
   }

   /// Adds [element] to the end of the list of elements associated with
   /// ([line],[column]).
   void add(int line, int column, T element) {
     _getList(line, column).add(element);
   }

   /// Adds [element] to the beginning of the list of elements associated with
   /// ([line],[column]).
   void addFirst(int line, int column, T element) {
     _getList(line, column).insert(0, element);
   }

   /// Calls [f] with the line number for each line with associated elements.
   ///
   /// [f] is called in increasing line order.
   void forEachLine(f(int line)) {
     List<int> lines = _map.keys.toList()..sort();
     lines.forEach(f);
   }

   /// Returns the elements for the first the column in [line] that has
   /// associated elements.
   List<T> getFirstElementsInLine(int line) {
     Map<int, List<T>> lineMap = _map[line];
     if (lineMap == null) return null;
     List<int> columns = lineMap.keys.toList()..sort();
     return lineMap[columns.first];
   }

   /// Calls [f] for each column with associated elements in [line].
   ///
   /// [f] is called in increasing column order.
   void forEachColumn(int line, f(int column, List<T> elements)) {
     Map<int, List<T>> lineMap = _map[line];
     if (lineMap != null) {
       List<int> columns = lineMap.keys.toList()..sort();
       columns.forEach((int column) {
         f(column, lineMap[column]);
       });
     }
   }

   /// Calls [f] for each line/column/element triplet in the map.
   ///
   /// [f] is called in increasing line, column, element order.
   void forEach(f(int line, int column, T element)) {
     List<int> lines = _map.keys.toList()..sort();
     for (int line in lines) {
       Map<int, List<T>> lineMap = _map[line];
       List<int> columns = lineMap.keys.toList()..sort();
       for (int column in columns) {
         lineMap[column].forEach((e) => f(line, column, e));
       }
     }
   }

   /// Calls [f] for each element associated in the map.
   ///
   /// [f] is called in increasing line, column, element order.
   void forEachElement(f(T element)) {
     forEach((line, column, element) => f(element));
   }
 }

 /// Map from [T] elements to assigned indices.
 class IndexMap<T> {
   Map<T, int> map = <T, int>{};

   /// Register [element] and returns its index.
   int register(T element) {
     return map.putIfAbsent(element, () => map.length);
   }

   /// Returns the index of [element].
   int operator [](T element) => map[element];

   /// Returns the indexed elements.
   Iterable<T> get elements => map.keys;
 }
	// Copyright (c) 2012, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	library dart2js.source_map_builder;

	import '../util/uri_extras.dart' show relativize;
	import '../util/util.dart';
	import 'line_column_provider.dart';
	import 'source_information.dart' show SourceLocation;

	class SourceMapBuilder {
	/// The URI of the source map file.
	final Uri sourceMapUri;

	/// The URI of the target language file.
	final Uri targetFileUri;

	final LineColumnProvider lineColumnProvider;
	final List<SourceMapEntry> entries = new List<SourceMapEntry>();

	SourceMapBuilder(
	this.sourceMapUri, this.targetFileUri, this.lineColumnProvider);

	void addMapping(int targetOffset, SourceLocation sourceLocation) {
	entries.add(new SourceMapEntry(sourceLocation, targetOffset));
	}

	void printStringListOn(Iterable<String> strings, StringBuffer buffer) {
	bool first = true;
	buffer.write('[');
	for (String string in strings) {
	if (!first) buffer.write(',');
	buffer.write('"');
	writeJsonEscapedCharsOn(string, buffer);
	buffer.write('"');
	first = false;
	}
	buffer.write(']');
	}

	String build() {
	LineColumnMap<SourceMapEntry> lineColumnMap =
	new LineColumnMap<SourceMapEntry>();
	Map<Uri, LineColumnMap<SourceMapEntry>> sourceLocationMap =
	<Uri, LineColumnMap<SourceMapEntry>>{};
	entries.forEach((SourceMapEntry sourceMapEntry) {
	int line = lineColumnProvider.getLine(sourceMapEntry.targetOffset);
	int column =
	lineColumnProvider.getColumn(line, sourceMapEntry.targetOffset);
	lineColumnMap.add(line, column, sourceMapEntry);

	SourceLocation location = sourceMapEntry.sourceLocation;
	if (location != null) {
	if (location.sourceUri != null) {
	LineColumnMap<SourceMapEntry> sourceLineColumnMap =
	sourceLocationMap.putIfAbsent(location.sourceUri,
	() => new LineColumnMap<SourceMapEntry>());
	sourceLineColumnMap.add(
	location.line, location.column, sourceMapEntry);
	}
	}
	});

	return _build(lineColumnMap);
	}

	String _build(LineColumnMap<SourceMapEntry> lineColumnMap) {
	IndexMap<Uri> uriMap = new IndexMap<Uri>();
	IndexMap<String> nameMap = new IndexMap<String>();

	lineColumnMap.forEachElement((SourceMapEntry entry) {
	SourceLocation sourceLocation = entry.sourceLocation;
	if (sourceLocation != null) {
	if (sourceLocation.sourceUri != null) {
	uriMap.register(sourceLocation.sourceUri);
	if (sourceLocation.sourceName != null) {
	nameMap.register(sourceLocation.sourceName);
	}
	}
	}
	});

	StringBuffer mappingsBuffer = new StringBuffer();
	writeEntries(lineColumnMap, uriMap, nameMap, mappingsBuffer);

	StringBuffer buffer = new StringBuffer();
	buffer.write('{\n');
	buffer.write(' "version": 3,\n');
	if (sourceMapUri != null && targetFileUri != null) {
	buffer.write(
	' "file": "${relativize(sourceMapUri, targetFileUri, false)}",\n');
	}
	buffer.write(' "sourceRoot": "",\n');
	buffer.write(' "sources": ');
	Iterable<String> relativeSourceUriList = const <String>[];
	if (sourceMapUri != null) {
	relativeSourceUriList =
	uriMap.elements.map((u) => relativize(sourceMapUri, u, false));
	}
	printStringListOn(relativeSourceUriList, buffer);
	buffer.write(',\n');
	buffer.write(' "names": ');
	printStringListOn(nameMap.elements, buffer);
	buffer.write(',\n');
	buffer.write(' "mappings": "');
	buffer.write(mappingsBuffer);
	buffer.write('"\n}\n');
	return buffer.toString();
	}

	void writeEntries(LineColumnMap<SourceMapEntry> entries, IndexMap<Uri> uriMap,
	IndexMap<String> nameMap, StringBuffer output) {
	SourceLocation previousSourceLocation;
	int previousTargetLine = 0;
	DeltaEncoder targetColumnEncoder = new DeltaEncoder();
	bool firstEntryInLine = true;
	DeltaEncoder sourceUriIndexEncoder = new DeltaEncoder();
	DeltaEncoder sourceLineEncoder = new DeltaEncoder();
	DeltaEncoder sourceColumnEncoder = new DeltaEncoder();
	DeltaEncoder sourceNameIndexEncoder = new DeltaEncoder();

	entries.forEach((int targetLine, int targetColumn, SourceMapEntry entry) {
	SourceLocation sourceLocation = entry.sourceLocation;
	if (sourceLocation == previousSourceLocation) {
	return;
	}

	if (targetLine > previousTargetLine) {
	for (int i = previousTargetLine; i < targetLine; ++i) {
	output.write(';');
	}
	previousTargetLine = targetLine;
	previousSourceLocation = null;
	targetColumnEncoder.reset();
	firstEntryInLine = true;
	}

	if (!firstEntryInLine) {
	output.write(',');
	}
	firstEntryInLine = false;

	targetColumnEncoder.encode(output, targetColumn);

	if (sourceLocation == null) {
	return;
	}

	Uri sourceUri = sourceLocation.sourceUri;
	if (sourceUri != null) {
	sourceUriIndexEncoder.encode(output, uriMap[sourceUri]);
	sourceLineEncoder.encode(output, sourceLocation.line);
	sourceColumnEncoder.encode(output, sourceLocation.column);
	}

	String sourceName = sourceLocation.sourceName;
	if (sourceName != null) {
	sourceNameIndexEncoder.encode(output, nameMap[sourceName]);
	}

	previousSourceLocation = sourceLocation;
	});
	}
	}

	/// Encoder for value deltas in VLQ format.
	class DeltaEncoder {
	/// The last emitted value of the encoder.
	int _value = 0;

	/// Reset the encoder to its initial state.
	void reset() {
	_value = 0;
	}

	/// Writes the VLQ of delta between [value] and the last emitted value into
	/// [output] and updates the last emitted value of the encoder.
	void encode(StringBuffer output, int value) {
	_value = encodeVLQ(output, value, _value);
	}

	static const int VLQ_BASE_SHIFT = 5;
	static const int VLQ_BASE_MASK = (1 << 5) - 1;
	static const int VLQ_CONTINUATION_BIT = 1 << 5;
	static const int VLQ_CONTINUATION_MASK = 1 << 5;
	static const String BASE64_DIGITS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmn'
	'opqrstuvwxyz0123456789+/';

	/// Writes the VLQ of delta between [value] and [offset] into [output] and
	/// return [value].
	static int encodeVLQ(StringBuffer output, int value, int offset) {
	int delta = value - offset;
	int signBit = 0;
	if (delta < 0) {
	signBit = 1;
	delta = -delta;
	}
	delta = (delta << 1) \| signBit;
	do {
	int digit = delta & VLQ_BASE_MASK;
	delta >>= VLQ_BASE_SHIFT;
	if (delta > 0) {
	digit \|= VLQ_CONTINUATION_BIT;
	}
	output.write(BASE64_DIGITS[digit]);
	} while (delta > 0);
	return value;
	}
	}

	class SourceMapEntry {
	SourceLocation sourceLocation;
	int targetOffset;

	SourceMapEntry(this.sourceLocation, this.targetOffset);
	}

	/// Map from line/column pairs to lists of [T] elements.
	class LineColumnMap<T> {
	Map<int, Map<int, List<T>>> _map = <int, Map<int, List<T>>>{};

	/// Returns the list of elements associated with ([line],[column]).
	List<T> _getList(int line, int column) {
	Map<int, List<T>> lineMap = _map.putIfAbsent(line, () => <int, List<T>>{});
	return lineMap.putIfAbsent(column, () => <T>[]);
	}

	/// Adds [element] to the end of the list of elements associated with
	/// ([line],[column]).
	void add(int line, int column, T element) {
	_getList(line, column).add(element);
	}

	/// Adds [element] to the beginning of the list of elements associated with
	/// ([line],[column]).
	void addFirst(int line, int column, T element) {
	_getList(line, column).insert(0, element);
	}

	/// Calls [f] with the line number for each line with associated elements.
	///
	/// [f] is called in increasing line order.
	void forEachLine(f(int line)) {
	List<int> lines = _map.keys.toList()..sort();
	lines.forEach(f);
	}

	/// Returns the elements for the first the column in [line] that has
	/// associated elements.
	List<T> getFirstElementsInLine(int line) {
	Map<int, List<T>> lineMap = _map[line];
	if (lineMap == null) return null;
	List<int> columns = lineMap.keys.toList()..sort();
	return lineMap[columns.first];
	}

	/// Calls [f] for each column with associated elements in [line].
	///
	/// [f] is called in increasing column order.
	void forEachColumn(int line, f(int column, List<T> elements)) {
	Map<int, List<T>> lineMap = _map[line];
	if (lineMap != null) {
	List<int> columns = lineMap.keys.toList()..sort();
	columns.forEach((int column) {
	f(column, lineMap[column]);
	});
	}
	}

	/// Calls [f] for each line/column/element triplet in the map.
	///
	/// [f] is called in increasing line, column, element order.
	void forEach(f(int line, int column, T element)) {
	List<int> lines = _map.keys.toList()..sort();
	for (int line in lines) {
	Map<int, List<T>> lineMap = _map[line];
	List<int> columns = lineMap.keys.toList()..sort();
	for (int column in columns) {
	lineMap[column].forEach((e) => f(line, column, e));
	}
	}
	}

	/// Calls [f] for each element associated in the map.
	///
	/// [f] is called in increasing line, column, element order.
	void forEachElement(f(T element)) {
	forEach((line, column, element) => f(element));
	}
	}

	/// Map from [T] elements to assigned indices.
	class IndexMap<T> {
	Map<T, int> map = <T, int>{};

	/// Register [element] and returns its index.
	int register(T element) {
	return map.putIfAbsent(element, () => map.length);
	}

	/// Returns the index of [element].
	int operator [](T element) => map[element];

	/// Returns the indexed elements.
	Iterable<T> get elements => map.keys;
	}