pkg/analysis_server/lib/src/edit/nnbd_migration/instrumentation_renderer.dart - sdk.git - Git at Google

 // Copyright (c) 2019, 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.

 import 'dart:convert' show htmlEscape, LineSplitter;

 import 'package:analysis_server/src/edit/nnbd_migration/migration_info.dart';
 import 'package:analysis_server/src/edit/nnbd_migration/offset_mapper.dart';
 import 'package:analysis_server/src/edit/nnbd_migration/path_mapper.dart';
 import 'package:meta/meta.dart';
 import 'package:mustache/mustache.dart' as mustache;
 import 'package:path/path.dart' as path;

 /// A mustache template for one library's instrumentation output.
 mustache.Template _template = mustache.Template(r'''
 <html>
   <head>
     <title>Non-nullable fix instrumentation report</title>
     <script src="{{ highlightJsPath }}"></script>
     <script>
     function getHash(location) {
       var index = location.lastIndexOf("#");
       if (index >= 0) {
         return location.substring(index + 1);
       } else {
         return null;
       }
     }

     function highlightTarget(event) {
       if (event !== undefined && event.oldURL !== undefined) {
         // Remove the "target" CSS class from the previous anchor.
         var oldHash = getHash(event.oldURL);
         if (oldHash != null) {
           var anchor = document.getElementById(oldHash);
           if (anchor != null) {
             anchor.classList.remove("target");
           }
         }
       }
       var url = document.URL;
       var hash = getHash(url);
       if (hash != null) {
         var anchor = document.getElementById(hash);
         if (anchor != null) {
           anchor.classList.add("target");
         }
       }
     }

     document.addEventListener("DOMContentLoaded", highlightTarget);
     window.addEventListener("hashchange", highlightTarget);
     </script>
     <link rel="stylesheet" href="{{ highlightStylePath }}">
     <style>
 a:link {
   color: inherit;
   text-decoration-line: none;
 }

 a:visited {
   color: inherit;
   text-decoration-line: none;
 }

 a:hover {
   text-decoration-line: underline;
 }

 body {
   font-family: sans-serif;
   padding: 1em;
 }

 h2 {
   font-size: 1em;
   font-weight: bold;
 }

 .code {
   left: 0.5em;
   padding-left: 60px;
   position: absolute;
   top: 0.5em;
 }

 .content {
   font-family: monospace;
   position: relative;
   white-space: pre;
 }

 .regions {
   padding: 0.5em;
   position: absolute;
   left: 0.5em;
   top: 0.5em;
   /* The content of the regions is not visible; the user instead will see the
    * highlighted copy of the content. */
   visibility: hidden;
 }

 .regions table {
   border-spacing: 0;
 }

 .regions td {
   border: none;
   padding: 0;
   white-space: pre;
 }

 .regions td:empty:after {
   content: "\00a0";
 }

 .regions td.line-no {
   color: #999999;
   padding-right: 4px;
   text-align: right;
   visibility: visible;
   width: 50px;
 }

 .region {
   /* Green means this region was added. */
   background-color: #ccffcc;
   color: #003300;
   cursor: default;
   display: inline-block;
   position: relative;
   visibility: visible;
 }

 .region .tooltip {
   background-color: #EEE;
   border: solid 2px #999;
   color: #333;
   cursor: auto;
   font-family: sans-serif;
   font-size: 0.8em;
   left: 0;
   margin-left: 0;
   padding: 1px;
   position: absolute;
   top: 100%;
   visibility: hidden;
   white-space: normal;
   width: 400px;
   z-index: 1;
 }

 .region .tooltip > * {
   margin: 1em;
 }

 .region:hover .tooltip {
   visibility: visible;
 }

 .target {
   background-color: #FFFF99;
   position: relative;
   visibility: visible;
 }
     </style>
   </head>
   <body>
     <h1>Non-nullable fix instrumentation report</h1>
     <p><em>Well-written introduction to this report.</em></p>
     <div class="navigation">
       {{# links }}
         {{# isLink }}<a href="{{ href }}">{{ name }}</a>{{/ isLink }}
         {{^ isLink }}{{ name }}{{/ isLink }}
         <br />
       {{/ links }}
     </div>
     {{# units }}'''
     '<h2>{{{ path }}}</h2>'
     '<div class="content">'
     '<div class="code">'
     '{{! Write the file content, modified to include navigation information, }}'
     '{{! both anchors and links. }}'
     '{{{ navContent }}}'
     '</div>'
     '<div class="regions">'
     '{{! The regions are then written again, overlaying the first copy of }}'
     '{{! the content, to provide tooltips for modified regions. }}'
     '{{{ regionContent }}}'
     '</div></div>'
     r'''
     {{/ units }}
     <script lang="javascript">
 document.addEventListener("DOMContentLoaded", (event) => {
   document.querySelectorAll(".code").forEach((block) => {
     hljs.highlightBlock(block);
   });
 });
     </script>
   </body>
 </html>''');

 /// Instrumentation display output for a library that was migrated to use
 /// non-nullable types.
 class InstrumentationRenderer {
   /// Display information for a compilation unit.
   final UnitInfo unitInfo;

   /// Information for a whole migration, so that libraries can reference each
   /// other.
   final MigrationInfo migrationInfo;

   /// An object used to map the file paths of analyzed files to the file paths
   /// of the HTML files used to view the content of those files.
   final PathMapper pathMapper;

   /// Creates an output object for the given library info.
   InstrumentationRenderer(this.unitInfo, this.migrationInfo, this.pathMapper);

   /// Return the path context used to manipulate paths.
   path.Context get pathContext => migrationInfo.pathContext;

   /// Builds an HTML view of the instrumentation information in [unitInfo].
   String render() {
     Map<String, dynamic> mustacheContext = {
       'units': <Map<String, dynamic>>[],
       'links': migrationInfo.unitLinks(unitInfo),
       'highlightJsPath': migrationInfo.highlightJsPath(unitInfo),
       'highlightStylePath': migrationInfo.highlightStylePath(unitInfo),
       'navContent': _computeNavigationContent(unitInfo),
     };
     mustacheContext['units'].add({
       'path': unitInfo.path,
       'regionContent': _computeRegionContent(unitInfo),
     });
     return _template.renderString(mustacheContext);
   }

   /// Return the content of the file with navigation links and anchors added.
   String _computeNavigationContent(UnitInfo unitInfo) {
     String unitDir = _directoryContaining(unitInfo);
     String content = unitInfo.content;
     OffsetMapper mapper = unitInfo.offsetMapper;
     Map<int, String> openInsertions = {};
     Map<int, String> closeInsertions = {};
     //
     // Compute insertions for navigation targets.
     //
     for (NavigationTarget region in unitInfo.targets) {
       int openOffset = mapper.map(region.offset);
       String openInsertion = openInsertions[openOffset] ?? '';
       openInsertion = '<a id="o${region.offset}">$openInsertion';
       openInsertions[openOffset] = openInsertion;

       int closeOffset = openOffset + region.length;
       String closeInsertion = closeInsertions[closeOffset] ?? '';
       closeInsertion = '$closeInsertion</a>';
       closeInsertions[closeOffset] = closeInsertion;
     }
     //
     // Compute insertions for navigation sources, but skip the sources that
     // point at themselves.
     //
     for (NavigationSource region in unitInfo.sources ?? <NavigationSource>[]) {
       int openOffset = mapper.map(region.offset);
       NavigationTarget target = region.target;
       if (target.filePath != unitInfo.path || region.offset != target.offset) {
         String openInsertion = openInsertions[openOffset] ?? '';
         String htmlPath = pathContext.relative(pathMapper.map(target.filePath),
             from: unitDir);
         openInsertion = '<a href="$htmlPath#o${target.offset}">$openInsertion';
         openInsertions[openOffset] = openInsertion;

         int closeOffset = openOffset + region.length;
         String closeInsertion = closeInsertions[closeOffset] ?? '';
         closeInsertion = '$closeInsertion</a>';
         closeInsertions[closeOffset] = closeInsertion;
       }
     }
     //
     // Apply the insertions that have been computed.
     //
     List<int> offsets = []
       ..addAll(openInsertions.keys)
       ..addAll(closeInsertions.keys);
     offsets.sort();
     StringBuffer navContent2 = StringBuffer();
     int previousOffset2 = 0;
     for (int offset in offsets) {
       navContent2.write(content.substring(previousOffset2, offset));
       navContent2.write(closeInsertions[offset] ?? '');
       navContent2.write(openInsertions[offset] ?? '');
       previousOffset2 = offset;
     }
     if (previousOffset2 < content.length) {
       navContent2.write(content.substring(previousOffset2));
     }
     return navContent2.toString();
   }

   /// Return the content of regions, based on the [unitInfo] for both
   /// unmodified and modified regions.
   String _computeRegionContent(UnitInfo unitInfo) {
     String unitDir = _directoryContaining(unitInfo);
     String content = unitInfo.content;
     StringBuffer regions = StringBuffer();
     int lineNumber = 1;

     void writeSplitLines(String lines) {
       Iterator<String> lineIterator = LineSplitter.split(lines).iterator;
       lineIterator.moveNext();

       while (true) {
         regions.write(htmlEscape.convert(lineIterator.current));
         if (lineIterator.moveNext()) {
           // If we're not on the last element, end this table row, and start a
           // new table row.
           lineNumber++;
           regions.write(
               '</td></tr>' '<tr><td class="line-no">$lineNumber</td><td>');
         } else {
           break;
         }
       }
     }

     int previousOffset = 0;
     regions.write('<table><tbody><tr><td class="line-no">$lineNumber</td><td>');
     for (var region in unitInfo.regions) {
       int offset = region.offset;
       int length = region.length;
       if (offset > previousOffset) {
         // Display a region of unmodified content.
         writeSplitLines(content.substring(previousOffset, offset));
         previousOffset = offset + length;
       }
       regions.write('<span class="region">'
           '${content.substring(offset, offset + length)}'
           '<span class="tooltip">'
           '<p>${region.explanation}</p>');
       if (region.details.isNotEmpty) {
         regions.write('<ul>');
       }
       for (var detail in region.details) {
         regions.write('<li>');

         if (detail.target != null) {
           regions.write('<a href="${_uriForTarget(detail.target, unitDir)}">');
         }
         writeSplitLines(detail.description);
         if (detail.target != null) {
           regions.write('</a>');
         }
         regions.write('</li>');
       }
       if (region.details.isNotEmpty) {
         regions.write('</ul>');
       }
       regions.write('</span></span>');
     }
     if (previousOffset < content.length) {
       // Last region of unmodified content.
       writeSplitLines(content.substring(previousOffset));
     }
     regions.write('</td></tr></tbody></table>');
     return regions.toString();
   }

   /// Return the path to the directory containing the output generated from the
   /// [unitInfo].
   String _directoryContaining(UnitInfo unitInfo) {
     return pathContext.dirname(pathMapper.map(unitInfo.path));
   }

   /// Return the URL that will navigate to the given [target].
   String _uriForTarget(NavigationTarget target, String unitDir) {
     if (target == null) {
       // TODO(brianwilkerson) This is temporary support until we can get targets
       //  for all nodes.
       return '';
     }
     String relativePath =
         pathContext.relative(pathMapper.map(target.filePath), from: unitDir);
     return '$relativePath#o${target.offset.toString()}';
   }
 }

 /// A class storing rendering information for an entire migration report.
 ///
 /// This generally provides one [InstrumentationRenderer] (for one library)
 /// with information about the rest of the libraries represented in the
 /// instrumentation output.
 class MigrationInfo {
   /// The information about the compilation units that are are migrated.
   final Set<UnitInfo> units;

   /// The resource provider's path context.
   final path.Context pathContext;

   /// The filesystem root used to create relative paths for each unit.
   final String includedRoot;

   MigrationInfo(this.units, this.pathContext, this.includedRoot);

   /// The path to the highlight.js script, relative to [unitInfo].
   String highlightJsPath(UnitInfo unitInfo) => pathContext.relative(
       pathContext.join(includedRoot, '..', 'highlight.pack.js'),
       from: pathContext.dirname(unitInfo.path));

   /// The path to the highlight.js stylesheet, relative to [unitInfo].
   String highlightStylePath(UnitInfo unitInfo) => pathContext.relative(
       pathContext.join(includedRoot, '..', 'androidstudio.css'),
       from: pathContext.dirname(unitInfo.path));

   /// Generate mustache context for unit links, for navigation in the
   /// instrumentation document for [thisUnit].
   List<Map<String, Object>> unitLinks(UnitInfo thisUnit) {
     return [
       for (var unit in units)
         {
           'name': _computeName(unit),
           'isLink': unit != thisUnit,
           if (unit != thisUnit) 'href': _pathTo(target: unit, source: thisUnit)
         }
     ];
   }

   /// Return the path to [unit] from [includedRoot], to be used as a display
   /// name for a library.
   String _computeName(UnitInfo unit) =>
       pathContext.relative(unit.path, from: includedRoot);

   /// The path to [target], relative to [from].
   String _pathTo({@required UnitInfo target, @required UnitInfo source}) {
     String targetPath = pathContext.setExtension(target.path, '.html');
     String sourceDir = pathContext.dirname(source.path);
     return pathContext.relative(targetPath, from: sourceDir);
   }
 }
	// Copyright (c) 2019, 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.

	import 'dart:convert' show htmlEscape, LineSplitter;

	import 'package:analysis_server/src/edit/nnbd_migration/migration_info.dart';
	import 'package:analysis_server/src/edit/nnbd_migration/offset_mapper.dart';
	import 'package:analysis_server/src/edit/nnbd_migration/path_mapper.dart';
	import 'package:meta/meta.dart';
	import 'package:mustache/mustache.dart' as mustache;
	import 'package:path/path.dart' as path;

	/// A mustache template for one library's instrumentation output.
	mustache.Template _template = mustache.Template(r'''
	<html>
	<head>
	<title>Non-nullable fix instrumentation report</title>
	<script src="{{ highlightJsPath }}"></script>
	<script>
	function getHash(location) {
	var index = location.lastIndexOf("#");
	if (index >= 0) {
	return location.substring(index + 1);
	} else {
	return null;
	}
	}

	function highlightTarget(event) {
	if (event !== undefined && event.oldURL !== undefined) {
	// Remove the "target" CSS class from the previous anchor.
	var oldHash = getHash(event.oldURL);
	if (oldHash != null) {
	var anchor = document.getElementById(oldHash);
	if (anchor != null) {
	anchor.classList.remove("target");
	}
	}
	}
	var url = document.URL;
	var hash = getHash(url);
	if (hash != null) {
	var anchor = document.getElementById(hash);
	if (anchor != null) {
	anchor.classList.add("target");
	}
	}
	}

	document.addEventListener("DOMContentLoaded", highlightTarget);
	window.addEventListener("hashchange", highlightTarget);
	</script>
	<link rel="stylesheet" href="{{ highlightStylePath }}">
	<style>
	a:link {
	color: inherit;
	text-decoration-line: none;
	}

	a:visited {
	color: inherit;
	text-decoration-line: none;
	}

	a:hover {
	text-decoration-line: underline;
	}

	body {
	font-family: sans-serif;
	padding: 1em;
	}

	h2 {
	font-size: 1em;
	font-weight: bold;
	}

	.code {
	left: 0.5em;
	padding-left: 60px;
	position: absolute;
	top: 0.5em;
	}

	.content {
	font-family: monospace;
	position: relative;
	white-space: pre;
	}

	.regions {
	padding: 0.5em;
	position: absolute;
	left: 0.5em;
	top: 0.5em;
	/* The content of the regions is not visible; the user instead will see the
	* highlighted copy of the content. */
	visibility: hidden;
	}

	.regions table {
	border-spacing: 0;
	}

	.regions td {
	border: none;
	padding: 0;
	white-space: pre;
	}

	.regions td:empty:after {
	content: "\00a0";
	}

	.regions td.line-no {
	color: #999999;
	padding-right: 4px;
	text-align: right;
	visibility: visible;
	width: 50px;
	}

	.region {
	/* Green means this region was added. */
	background-color: #ccffcc;
	color: #003300;
	cursor: default;
	display: inline-block;
	position: relative;
	visibility: visible;
	}

	.region .tooltip {
	background-color: #EEE;
	border: solid 2px #999;
	color: #333;
	cursor: auto;
	font-family: sans-serif;
	font-size: 0.8em;
	left: 0;
	margin-left: 0;
	padding: 1px;
	position: absolute;
	top: 100%;
	visibility: hidden;
	white-space: normal;
	width: 400px;
	z-index: 1;
	}

	.region .tooltip > * {
	margin: 1em;
	}

	.region:hover .tooltip {
	visibility: visible;
	}

	.target {
	background-color: #FFFF99;
	position: relative;
	visibility: visible;
	}
	</style>
	</head>
	<body>
	<h1>Non-nullable fix instrumentation report</h1>
	<p><em>Well-written introduction to this report.</em></p>
	<div class="navigation">
	{{# links }}
	{{# isLink }}<a href="{{ href }}">{{ name }}</a>{{/ isLink }}
	{{^ isLink }}{{ name }}{{/ isLink }}
	<br />
	{{/ links }}
	</div>
	{{# units }}'''
	'<h2>{{{ path }}}</h2>'
	'<div class="content">'
	'<div class="code">'
	'{{! Write the file content, modified to include navigation information, }}'
	'{{! both anchors and links. }}'
	'{{{ navContent }}}'
	'</div>'
	'<div class="regions">'
	'{{! The regions are then written again, overlaying the first copy of }}'
	'{{! the content, to provide tooltips for modified regions. }}'
	'{{{ regionContent }}}'
	'</div></div>'
	r'''
	{{/ units }}
	<script lang="javascript">
	document.addEventListener("DOMContentLoaded", (event) => {
	document.querySelectorAll(".code").forEach((block) => {
	hljs.highlightBlock(block);
	});
	});
	</script>
	</body>
	</html>''');

	/// Instrumentation display output for a library that was migrated to use
	/// non-nullable types.
	class InstrumentationRenderer {
	/// Display information for a compilation unit.
	final UnitInfo unitInfo;

	/// Information for a whole migration, so that libraries can reference each
	/// other.
	final MigrationInfo migrationInfo;

	/// An object used to map the file paths of analyzed files to the file paths
	/// of the HTML files used to view the content of those files.
	final PathMapper pathMapper;

	/// Creates an output object for the given library info.
	InstrumentationRenderer(this.unitInfo, this.migrationInfo, this.pathMapper);

	/// Return the path context used to manipulate paths.
	path.Context get pathContext => migrationInfo.pathContext;

	/// Builds an HTML view of the instrumentation information in [unitInfo].
	String render() {
	Map<String, dynamic> mustacheContext = {
	'units': <Map<String, dynamic>>[],
	'links': migrationInfo.unitLinks(unitInfo),
	'highlightJsPath': migrationInfo.highlightJsPath(unitInfo),
	'highlightStylePath': migrationInfo.highlightStylePath(unitInfo),
	'navContent': _computeNavigationContent(unitInfo),
	};
	mustacheContext['units'].add({
	'path': unitInfo.path,
	'regionContent': _computeRegionContent(unitInfo),
	});
	return _template.renderString(mustacheContext);
	}

	/// Return the content of the file with navigation links and anchors added.
	String _computeNavigationContent(UnitInfo unitInfo) {
	String unitDir = _directoryContaining(unitInfo);
	String content = unitInfo.content;
	OffsetMapper mapper = unitInfo.offsetMapper;
	Map<int, String> openInsertions = {};
	Map<int, String> closeInsertions = {};
	//
	// Compute insertions for navigation targets.
	//
	for (NavigationTarget region in unitInfo.targets) {
	int openOffset = mapper.map(region.offset);
	String openInsertion = openInsertions[openOffset] ?? '';
	openInsertion = '<a id="o${region.offset}">$openInsertion';
	openInsertions[openOffset] = openInsertion;

	int closeOffset = openOffset + region.length;
	String closeInsertion = closeInsertions[closeOffset] ?? '';
	closeInsertion = '$closeInsertion</a>';
	closeInsertions[closeOffset] = closeInsertion;
	}
	//
	// Compute insertions for navigation sources, but skip the sources that
	// point at themselves.
	//
	for (NavigationSource region in unitInfo.sources ?? <NavigationSource>[]) {
	int openOffset = mapper.map(region.offset);
	NavigationTarget target = region.target;
	if (target.filePath != unitInfo.path \|\| region.offset != target.offset) {
	String openInsertion = openInsertions[openOffset] ?? '';
	String htmlPath = pathContext.relative(pathMapper.map(target.filePath),
	from: unitDir);
	openInsertion = '<a href="$htmlPath#o${target.offset}">$openInsertion';
	openInsertions[openOffset] = openInsertion;

	int closeOffset = openOffset + region.length;
	String closeInsertion = closeInsertions[closeOffset] ?? '';
	closeInsertion = '$closeInsertion</a>';
	closeInsertions[closeOffset] = closeInsertion;
	}
	}
	//
	// Apply the insertions that have been computed.
	//
	List<int> offsets = []
	..addAll(openInsertions.keys)
	..addAll(closeInsertions.keys);
	offsets.sort();
	StringBuffer navContent2 = StringBuffer();
	int previousOffset2 = 0;
	for (int offset in offsets) {
	navContent2.write(content.substring(previousOffset2, offset));
	navContent2.write(closeInsertions[offset] ?? '');
	navContent2.write(openInsertions[offset] ?? '');
	previousOffset2 = offset;
	}
	if (previousOffset2 < content.length) {
	navContent2.write(content.substring(previousOffset2));
	}
	return navContent2.toString();
	}

	/// Return the content of regions, based on the [unitInfo] for both
	/// unmodified and modified regions.
	String _computeRegionContent(UnitInfo unitInfo) {
	String unitDir = _directoryContaining(unitInfo);
	String content = unitInfo.content;
	StringBuffer regions = StringBuffer();
	int lineNumber = 1;

	void writeSplitLines(String lines) {
	Iterator<String> lineIterator = LineSplitter.split(lines).iterator;
	lineIterator.moveNext();

	while (true) {
	regions.write(htmlEscape.convert(lineIterator.current));
	if (lineIterator.moveNext()) {
	// If we're not on the last element, end this table row, and start a
	// new table row.
	lineNumber++;
	regions.write(
	'</td></tr>' '<tr><td class="line-no">$lineNumber</td><td>');
	} else {
	break;
	}
	}
	}

	int previousOffset = 0;
	regions.write('<table><tbody><tr><td class="line-no">$lineNumber</td><td>');
	for (var region in unitInfo.regions) {
	int offset = region.offset;
	int length = region.length;
	if (offset > previousOffset) {
	// Display a region of unmodified content.
	writeSplitLines(content.substring(previousOffset, offset));
	previousOffset = offset + length;
	}
	regions.write('<span class="region">'
	'${content.substring(offset, offset + length)}'
	'<span class="tooltip">'
	'<p>${region.explanation}</p>');
	if (region.details.isNotEmpty) {
	regions.write('<ul>');
	}
	for (var detail in region.details) {
	regions.write('<li>');

	if (detail.target != null) {
	regions.write('<a href="${_uriForTarget(detail.target, unitDir)}">');
	}
	writeSplitLines(detail.description);
	if (detail.target != null) {
	regions.write('</a>');
	}
	regions.write('</li>');
	}
	if (region.details.isNotEmpty) {
	regions.write('</ul>');
	}
	regions.write('</span></span>');
	}
	if (previousOffset < content.length) {
	// Last region of unmodified content.
	writeSplitLines(content.substring(previousOffset));
	}
	regions.write('</td></tr></tbody></table>');
	return regions.toString();
	}

	/// Return the path to the directory containing the output generated from the
	/// [unitInfo].
	String _directoryContaining(UnitInfo unitInfo) {
	return pathContext.dirname(pathMapper.map(unitInfo.path));
	}

	/// Return the URL that will navigate to the given [target].
	String _uriForTarget(NavigationTarget target, String unitDir) {
	if (target == null) {
	// TODO(brianwilkerson) This is temporary support until we can get targets
	// for all nodes.
	return '';
	}
	String relativePath =
	pathContext.relative(pathMapper.map(target.filePath), from: unitDir);
	return '$relativePath#o${target.offset.toString()}';
	}
	}

	/// A class storing rendering information for an entire migration report.
	///
	/// This generally provides one [InstrumentationRenderer] (for one library)
	/// with information about the rest of the libraries represented in the
	/// instrumentation output.
	class MigrationInfo {
	/// The information about the compilation units that are are migrated.
	final Set<UnitInfo> units;

	/// The resource provider's path context.
	final path.Context pathContext;

	/// The filesystem root used to create relative paths for each unit.
	final String includedRoot;

	MigrationInfo(this.units, this.pathContext, this.includedRoot);

	/// The path to the highlight.js script, relative to [unitInfo].
	String highlightJsPath(UnitInfo unitInfo) => pathContext.relative(
	pathContext.join(includedRoot, '..', 'highlight.pack.js'),
	from: pathContext.dirname(unitInfo.path));

	/// The path to the highlight.js stylesheet, relative to [unitInfo].
	String highlightStylePath(UnitInfo unitInfo) => pathContext.relative(
	pathContext.join(includedRoot, '..', 'androidstudio.css'),
	from: pathContext.dirname(unitInfo.path));

	/// Generate mustache context for unit links, for navigation in the
	/// instrumentation document for [thisUnit].
	List<Map<String, Object>> unitLinks(UnitInfo thisUnit) {
	return [
	for (var unit in units)
	{
	'name': _computeName(unit),
	'isLink': unit != thisUnit,
	if (unit != thisUnit) 'href': _pathTo(target: unit, source: thisUnit)
	}
	];
	}

	/// Return the path to [unit] from [includedRoot], to be used as a display
	/// name for a library.
	String _computeName(UnitInfo unit) =>
	pathContext.relative(unit.path, from: includedRoot);

	/// The path to [target], relative to [from].
	String _pathTo({@required UnitInfo target, @required UnitInfo source}) {
	String targetPath = pathContext.setExtension(target.path, '.html');
	String sourceDir = pathContext.dirname(source.path);
	return pathContext.relative(targetPath, from: sourceDir);
	}
	}