mcs/tools/corcompare/mono-api-html/MemberComparer.cs

   1 //
   2 // Authors
   3 //    Sebastien Pouliot  <sebastien@xamarin.com>
   4 //
   5 // Copyright 2013-2014 Xamarin Inc. http://www.xamarin.com
   6 //
   7 // Permission is hereby granted, free of charge, to any person obtaining
   8 // a copy of this software and associated documentation files (the
   9 // "Software"), to deal in the Software without restriction, including
  10 // without limitation the rights to use, copy, modify, merge, publish,
  11 // distribute, sublicense, and/or sell copies of the Software, and to
  12 // permit persons to whom the Software is furnished to do so, subject to
  13 // the following conditions:
  14 //
  15 // The above copyright notice and this permission notice shall be
  16 // included in all copies or substantial portions of the Software.
  17 //
  18 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  21 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  22 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25 //
  26
  27 using System;
  28 using System.Collections.Generic;
  29 using System.Linq;
  30 using System.Reflection;
  31 using System.Text;
  32 using System.Xml.Linq;
  33
  34 namespace Xamarin.ApiDiff {
  35
  36         public abstract class MemberComparer : Comparer {
  37
  38                 // true if this is the first element being added or removed in the group being rendered
  39                 protected bool first;
  40
  41                 public abstract string GroupName { get; }
  42                 public abstract string ElementName { get; }
  43
  44                 protected virtual bool IsBreakingRemoval (XElement e)
  45                 {
  46                         return true;
  47                 }
  48
  49                 public void Compare (XElement source, XElement target)
  50                 {
  51                         var s = source.Element (GroupName);
  52                         var t = target.Element (GroupName);
  53                         if (XNode.DeepEquals (s, t))
  54                                 return;
  55
  56                         if (s == null) {
  57                                 Add (t.Elements (ElementName));
  58                         } else if (t == null) {
  59                                 Remove (s.Elements (ElementName));
  60                         } else {
  61                                 Compare (s.Elements (ElementName), t.Elements (ElementName));
  62                         }
  63                 }
  64
  65                 public override void SetContext (XElement current)
  66                 {
  67                 }
  68
  69                 string GetContainingType (XElement el)
  70                 {
  71                         return el.Ancestors ("class").First ().Attribute ("type").Value;
  72                 }
  73
  74                 bool IsInInterface (XElement el)
  75                 {
  76                         return GetContainingType (el) == "interface";
  77                 }
  78
  79                 public XElement Source { get; set; }
  80
  81                 public virtual bool Find (XElement e)
  82                 {
  83                         return e.GetAttribute ("name") == Source.GetAttribute ("name");
  84                 }
  85
  86                 XElement Find (IEnumerable<XElement> target)
  87                 {
  88                         return State.Lax ? target.FirstOrDefault (Find) : target.SingleOrDefault (Find);
  89                 }
  90
  91                 public override void Compare (IEnumerable<XElement> source, IEnumerable<XElement> target)
  92                 {
  93                         removed.Clear ();
  94                         modified.Clear ();
  95
  96                         foreach (var s in source) {
  97                                 SetContext (s);
  98                                 Source = s;
  99                                 var t = Find (target);
 100                                 if (t == null) {
 101                                         // not in target, it was removed
 102                                         removed.Add (s);
 103                                 } else {
 104                                         t.Remove ();
 105                                         // possibly modified
 106                                         if (Equals (s, t, modified))
 107                                                 continue;
 108
 109                                         Modified (s, t, modified);
 110                                 }
 111                         }
 112                         // delayed, that way we show "Modified", "Added" and then "Removed"
 113                         Remove (removed);
 114
 115                         Modify (modified);
 116
 117                         // remaining == newly added in target
 118                         Add (target);
 119                 }
 120
 121                 void Add (IEnumerable<XElement> elements)
 122                 {
 123                         bool a = false;
 124                         foreach (var item in elements) {
 125                                 SetContext (item);
 126                                 if (State.IgnoreAdded.Any (re => re.IsMatch (GetDescription (item))))
 127                                         continue;
 128                                 if (!a) {
 129                                         BeforeAdding (elements);
 130                                         a = true;
 131                                 }
 132                                 Added (item);
 133                         }
 134                         if (a)
 135                                 AfterAdding ();
 136                 }
 137
 138                 void Modify (ApiChanges modified)
 139                 {
 140                         foreach (var changes in modified) {
 141                                 Output.WriteLine ("<p>{0}:</p>", changes.Key);
 142                                 Output.WriteLine ("<pre>");
 143                                 foreach (var element in changes.Value) {
 144                                         Output.Write ("<div {0}>", element.Breaking ? "data-is-breaking" : "data-is-non-breaking");
 145                                         foreach (var line in element.Member.ToString ().Split ('\n'))
 146                                                 Output.WriteLine ("\t{0}", line);
 147                                         Output.Write ("</div>");
 148
 149                                 }
 150                                 Output.WriteLine ("</pre>");
 151                         }
 152                 }
 153
 154                 void Remove (IEnumerable<XElement> elements)
 155                 {
 156                         bool r = false;
 157                         foreach (var item in elements) {
 158                                 if (State.IgnoreRemoved.Any (re => re.IsMatch (GetDescription (item))))
 159                                         continue;
 160                                 SetContext (item);
 161                                 if (!r) {
 162                                         BeforeRemoving (elements);
 163                                         r = true;
 164                                 }
 165                                 Removed (item);
 166                         }
 167                         if (r)
 168                                 AfterRemoving ();
 169                 }
 170
 171                 public abstract string GetDescription (XElement e);
 172
 173                 protected StringBuilder GetObsoleteMessage (XElement e)
 174                 {
 175                         var sb = new StringBuilder ();
 176                         string o = e.GetObsoleteMessage ();
 177                         if (o != null) {
 178                                 sb.Append ("[Obsolete");
 179                                 if (o.Length > 0)
 180                                         sb.Append (" (\"").Append (o).Append ("\")");
 181                                 sb.AppendLine ("]");
 182                                 for (int i = 0; i < State.Indent + 1; i++)
 183                                         sb.Append ('\t');
 184                         }
 185                         return sb;
 186                 }
 187
 188                 public override bool Equals (XElement source, XElement target, ApiChanges changes)
 189                 {
 190                         RenderAttributes (source, target, changes);
 191
 192                         // We don't want to compare attributes.
 193                         RemoveAttributes (source);
 194                         RemoveAttributes (target);
 195
 196                         return base.Equals (source, target, changes);
 197                 }
 198
 199                 public virtual void BeforeAdding (IEnumerable<XElement> list)
 200                 {
 201                         first = true;
 202                         bool isInterface = list.Count () > 0 && IsInInterface (list.First ());
 203                         Output.WriteLine ("<div>");
 204                         Output.WriteLine ("<p>Added {0}:</p>", list.Count () > 1 ? GroupName : ElementName);
 205                         Output.WriteLine ("<pre>");
 206                 }
 207
 208                 public override void Added (XElement target)
 209                 {
 210                         var o = GetObsoleteMessage (target);
 211                         if (!first && (o.Length > 0))
 212                                 Output.WriteLine ();
 213                         Indent ();
 214                         bool isInterface = IsInInterface (target);
 215                         Output.Write ("\t<span class='added added-{0} {1}' {2}>", ElementName, isInterface ? "breaking" : string.Empty, isInterface ? "data-is-breaking" : "data-is-non-breaking");
 216                         Output.Write ("{0}{1}", o, GetDescription (target));
 217                         Output.WriteLine ("</span>");
 218                         first = false;
 219                 }
 220
 221                 public virtual void AfterAdding ()
 222                 {
 223                         Output.WriteLine ("</pre>");
 224                         Output.WriteLine ("</div>");
 225                 }
 226
 227                 public override void Modified (XElement source, XElement target, ApiChanges change)
 228                 {
 229                 }
 230
 231                 public virtual void BeforeRemoving (IEnumerable<XElement> list)
 232                 {
 233                         first = true;
 234                         Output.WriteLine ("<p>Removed {0}:</p>\n", list.Count () > 1 ? GroupName : ElementName);
 235                         Output.WriteLine ("<pre>");
 236                 }
 237
 238                 public override void Removed (XElement source)
 239                 {
 240                         var o = GetObsoleteMessage (source);
 241                         if (!first && (o.Length > 0))
 242                                 Output.WriteLine ();
 243
 244                         bool is_breaking = IsBreakingRemoval (source);
 245
 246                         Indent ();
 247                         Output.Write ("\t<span class='removed removed-{0} {2}' {1}>", ElementName, is_breaking ? "data-is-breaking" : "data-is-non-breaking", is_breaking ? "breaking" : string.Empty);
 248                         Output.Write ("{0}{1}", o, GetDescription (source));
 249                         Output.WriteLine ("</span>");
 250                         first = false;
 251                 }
 252
 253                 public virtual void AfterRemoving ()
 254                 {
 255                         Output.WriteLine ("</pre>");;
 256                 }
 257
 258                 string RenderGenericParameter (XElement gp)
 259                 {
 260                         var sb = new StringBuilder ();
 261                         sb.Append (gp.GetTypeName ("name"));
 262
 263                         var constraints = gp.DescendantList ("generic-parameter-constraints", "generic-parameter-constraint");
 264                         if (constraints != null && constraints.Count > 0) {
 265                                 sb.Append (" : ");
 266                                 for (int i = 0; i < constraints.Count; i++) {
 267                                         if (i > 0)
 268                                                 sb.Append (", ");
 269                                         sb.Append (constraints [i].GetTypeName ("name"));
 270                                 }
 271                         }
 272                         return sb.ToString ();
 273                 }
 274
 275                 protected void RenderGenericParameters (XElement source, XElement target, ApiChange change)
 276                 {
 277                         var src = source.DescendantList ("generic-parameters", "generic-parameter");
 278                         var tgt = target.DescendantList ("generic-parameters", "generic-parameter");
 279                         var srcCount = src == null ? 0 : src.Count;
 280                         var tgtCount = tgt == null ? 0 : tgt.Count;
 281
 282                         if (srcCount == 0 && tgtCount == 0)
 283                                 return;
 284
 285                         change.Append ("&lt;");
 286                         for (int i = 0; i < Math.Max (srcCount, tgtCount); i++) {
 287                                 if (i > 0)
 288                                         change.Append (", ");
 289                                 if (i >= srcCount) {
 290                                         change.AppendAdded (RenderGenericParameter (tgt [i]), true);
 291                                 } else if (i >= tgtCount) {
 292                                         change.AppendRemoved (RenderGenericParameter (src [i]), true);
 293                                 } else {
 294                                         var srcName = RenderGenericParameter (src [i]);
 295                                         var tgtName = RenderGenericParameter (tgt [i]);
 296
 297                                         if (srcName != tgtName) {
 298                                                 change.AppendModified (srcName, tgtName, true);
 299                                         } else {
 300                                                 change.Append (srcName);
 301                                         }
 302                                         }
 303                                 }
 304                         change.Append ("&gt;");
 305                 }
 306
 307                 protected string FormatValue (string type, string value)
 308                 {
 309                         if (value == null)
 310                                 return "null";
 311
 312                         if (type == "string")
 313                                 return "\"" + value + "\"";
 314                         else if (type == "bool") {
 315                                 switch (value) {
 316                                 case "True":
 317                                         return "true";
 318                                 case "False":
 319                                         return "false";
 320                                 default:
 321                                         return value;
 322                                 }
 323                         }
 324
 325                         return value;
 326                 }
 327
 328                 protected void RenderParameters (XElement source, XElement target, ApiChange change)
 329                 {
 330                         var src = source.DescendantList ("parameters", "parameter");
 331                         var tgt = target.DescendantList ("parameters", "parameter");
 332                         var srcCount = src == null ? 0 : src.Count;
 333                         var tgtCount = tgt == null ? 0 : tgt.Count;
 334
 335                         change.Append (" (");
 336                         for (int i = 0; i < Math.Max (srcCount, tgtCount); i++) {
 337                                 if (i > 0)
 338                                         change.Append (", ");
 339
 340                                 if (i >= srcCount) {
 341                                         change.AppendAdded (tgt [i].GetTypeName ("type") + " " + tgt [i].GetAttribute ("name"), true);
 342                                 } else if (i >= tgtCount) {
 343                                         change.AppendRemoved (src [i].GetTypeName ("type") + " " + src [i].GetAttribute ("name"), true);
 344                                 } else {
 345                                         var paramSourceType = src [i].GetTypeName ("type");
 346                                         var paramTargetType = tgt [i].GetTypeName ("type");
 347
 348                                         var paramSourceName = src [i].GetAttribute ("name");
 349                                         var paramTargetName = tgt [i].GetAttribute ("name");
 350
 351                                         if (paramSourceType != paramTargetType) {
 352                                                 change.AppendModified (paramSourceType, paramTargetType, true);
 353                                         } else {
 354                                                 change.Append (paramSourceType);
 355                                         }
 356                                         change.Append (" ");
 357                                         if (paramSourceName != paramTargetName) {
 358                                                 change.AppendModified (paramSourceName, paramTargetName, false);
 359                                         } else {
 360                                                 change.Append (paramSourceName);
 361                                         }
 362
 363                                         var optSource = src [i].Attribute ("optional");
 364                                         var optTarget = tgt [i].Attribute ("optional");
 365                                         var srcValue = FormatValue (paramSourceType, src [i].GetAttribute ("defaultValue"));
 366                                         var tgtValue = FormatValue (paramTargetType, tgt [i].GetAttribute ("defaultValue"));
 367
 368                                         if (optSource != null) {
 369                                                 if (optTarget != null) {
 370                                                         change.Append (" = ");
 371                                                         if (srcValue != tgtValue) {
 372                                                                 change.AppendModified (srcValue, tgtValue, false);
 373                                                         } else {
 374                                                                 change.Append (tgtValue);
 375                                                         }
 376                                                 } else {
 377                                                         change.AppendRemoved (" = " + srcValue);
 378                                                 }
 379                                         } else {
 380                                                 if (optTarget != null)
 381                                                         change.AppendAdded (" = " + tgtValue);
 382                                         }
 383                                 }
 384                         }
 385
 386                         change.Append (")");
 387
 388                         // Ignore any parameter name changes if requested.
 389                         if (State.IgnoreParameterNameChanges && !change.Breaking) {
 390                                 change.AnyChange = false;
 391                                 change.HasIgnoredChanges = true;
 392                         }
 393                 }
 394
 395                 void RenderVTable (MethodAttributes source, MethodAttributes target, ApiChange change)
 396                 {
 397                         var srcAbstract = (source & MethodAttributes.Abstract) == MethodAttributes.Abstract;
 398                         var tgtAbstract = (target & MethodAttributes.Abstract) == MethodAttributes.Abstract;
 399                         var srcFinal = (source & MethodAttributes.Final) == MethodAttributes.Final;
 400                         var tgtFinal = (target & MethodAttributes.Final) == MethodAttributes.Final;
 401                         var srcVirtual = (source & MethodAttributes.Virtual) == MethodAttributes.Virtual;
 402                         var tgtVirtual = (target & MethodAttributes.Virtual) == MethodAttributes.Virtual;
 403                         var srcOverride = (source & MethodAttributes.VtableLayoutMask) != MethodAttributes.NewSlot;
 404                         var tgtOverride = (target & MethodAttributes.VtableLayoutMask) != MethodAttributes.NewSlot;
 405
 406                         var srcWord = srcVirtual ? (srcOverride ? "override" : "virtual") : string.Empty;
 407                         var tgtWord = tgtVirtual ? (tgtOverride ? "override" : "virtual") : string.Empty;
 408                         var breaking = srcWord.Length > 0 && tgtWord.Length == 0;
 409
 410                         if (srcAbstract) {
 411                                 if (tgtAbstract) {
 412                                         change.Append ("abstract ");
 413                                 } else if (tgtVirtual) {
 414                                         change.AppendModified ("abstract", tgtWord, false).Append (" ");
 415                                 } else {
 416                                         change.AppendRemoved ("abstract").Append (" ");
 417                                 }
 418                         } else {
 419                                 if (tgtAbstract) {
 420                                         change.AppendAdded ("abstract", true).Append (" ");
 421                                 } else if (srcWord != tgtWord) {
 422                                         if (!tgtFinal)
 423                                                 change.AppendModified (srcWord, tgtWord, breaking).Append (" ");
 424                                 } else if (tgtWord.Length > 0) {
 425                                         change.Append (tgtWord).Append (" ");
 426                                 } else if (srcWord.Length > 0) {
 427                                         change.AppendRemoved (srcWord, breaking).Append (" ");
 428                                 }
 429                         }
 430
 431                         if (srcFinal) {
 432                                 if (tgtFinal) {
 433                                         change.Append ("final ");
 434                                 } else {
 435                                         change.AppendRemoved ("final", false).Append (" "); // removing 'final' is not a breaking change.
 436                                 }
 437                         } else {
 438                                 if (tgtFinal && srcVirtual) {
 439                                         change.AppendModified ("virtual", "final", true).Append (" "); // adding 'final' is a breaking change if the member was virtual
 440                                 }
 441                         }
 442
 443                         if (!srcVirtual && !srcFinal && tgtVirtual && tgtFinal) {
 444                                 // existing member implements a member from a new interface
 445                                 // this would show up as 'virtual final', which is redundant, so show nothing at all.
 446                                 change.HasIgnoredChanges = true;
 447                         }
 448
 449                         // Ignore non-breaking virtual changes.
 450                         if (State.IgnoreVirtualChanges && !change.Breaking) {
 451                                 change.AnyChange = false;
 452                                 change.HasIgnoredChanges = true;
 453                         }
 454
 455                         var tgtSecurity = (source & MethodAttributes.HasSecurity) == MethodAttributes.HasSecurity;
 456                         var srcSecurity = (target & MethodAttributes.HasSecurity) == MethodAttributes.HasSecurity;
 457
 458                         if (tgtSecurity != srcSecurity)
 459                                 change.HasIgnoredChanges = true;
 460
 461                         var srcPInvoke = (source & MethodAttributes.PinvokeImpl) == MethodAttributes.PinvokeImpl;
 462                         var tgtPInvoke = (target & MethodAttributes.PinvokeImpl) == MethodAttributes.PinvokeImpl;
 463                         if (srcPInvoke != tgtPInvoke)
 464                                 change.HasIgnoredChanges = true;
 465                 }
 466
 467                 protected string GetVisibility (MethodAttributes attr)
 468                 {
 469                         switch (attr) {
 470                         case MethodAttributes.Private:
 471                         case MethodAttributes.PrivateScope:
 472                                 return "private";
 473                         case MethodAttributes.Assembly:
 474                                 return "internal";
 475                         case MethodAttributes.FamANDAssem:
 476                                 return "private internal";
 477                         case MethodAttributes.FamORAssem:
 478                                 return "protected"; // customers don't care about 'internal';
 479                         case MethodAttributes.Family:
 480                                 return "protected";
 481                         case MethodAttributes.Public:
 482                                 return "public";
 483                         default:
 484                                 throw new NotImplementedException ();
 485                         }
 486                 }
 487
 488                 protected void RenderVisibility (MethodAttributes source, MethodAttributes target, ApiChange diff)
 489                 {
 490                         source = source & MethodAttributes.MemberAccessMask;
 491                         target = target & MethodAttributes.MemberAccessMask;
 492
 493                         if (source == target) {
 494                                 diff.Append (GetVisibility (target));
 495                         } else {
 496                                 var breaking = false;
 497                                 switch (source) {
 498                                 case MethodAttributes.Private:
 499                                 case MethodAttributes.Assembly:
 500                                 case MethodAttributes.FamANDAssem:
 501                                         break; // these are not publicly visible, thus not breaking
 502                                 case MethodAttributes.FamORAssem:
 503                                 case MethodAttributes.Family:
 504                                         switch (target) {
 505                                         case MethodAttributes.Public:
 506                                                 // to public is not a breaking change
 507                                                 break;
 508                                         case MethodAttributes.Family:
 509                                         case MethodAttributes.FamORAssem:
 510                                                 // not a breaking change, but should still show up in diff
 511                                                 break;
 512                                         default:
 513                                                 // anything else is a breaking change
 514                                                 breaking = true;
 515                                                 break;
 516                                         }
 517                                         break;
 518                                 case MethodAttributes.Public:
 519                                 default:
 520                                         // any change from public is breaking.
 521                                         breaking = true;
 522                                         break;
 523                                 }
 524
 525                                 diff.AppendModified (GetVisibility (source), GetVisibility (target), breaking);
 526                         }
 527                         diff.Append (" ");
 528                 }
 529
 530                 protected void RenderStatic (MethodAttributes src, MethodAttributes tgt, ApiChange diff)
 531                 {
 532                         var srcStatic = (src & MethodAttributes.Static) == MethodAttributes.Static;
 533                         var tgtStatic = (tgt & MethodAttributes.Static) == MethodAttributes.Static;
 534
 535                         if (srcStatic != tgtStatic) {
 536                                 if (srcStatic) {
 537                                         diff.AppendRemoved ("static", true).Append (" ");
 538                                 } else {
 539                                         diff.AppendAdded ("static", true).Append (" ");
 540                                 }
 541                         }
 542                 }
 543
 544                 protected void RenderMethodAttributes (MethodAttributes src, MethodAttributes tgt, ApiChange diff)
 545                 {
 546                         RenderStatic (src, tgt, diff);
 547                         RenderVisibility (src & MethodAttributes.MemberAccessMask, tgt & MethodAttributes.MemberAccessMask, diff);
 548                         RenderVTable (src, tgt, diff);
 549                 }
 550
 551                 protected void RenderMethodAttributes (XElement source, XElement target, ApiChange diff)
 552                 {
 553                         RenderMethodAttributes (source.GetMethodAttributes (), target.GetMethodAttributes (), diff);
 554                 }
 555
 556                 protected void RemoveAttributes (XElement element)
 557                 {
 558                         var srcAttributes = element.Element ("attributes");
 559                         if (srcAttributes != null)
 560                                 srcAttributes.Remove ();
 561
 562                         foreach (var el in element.Elements ())
 563                                 RemoveAttributes (el);
 564                 }
 565
 566                 protected void RenderAttributes (XElement source, XElement target, ApiChanges changes)
 567                 {
 568                         var srcObsolete = source.GetObsoleteMessage ();
 569                         var tgtObsolete = target.GetObsoleteMessage ();
 570
 571                         if (srcObsolete == tgtObsolete)
 572                                 return; // nothing changed
 573
 574                         if (srcObsolete == null) {
 575                                 if (tgtObsolete == null)
 576                                         return; // neither is obsolete
 577                                 var change = new ApiChange ();
 578                                 change.Header = "Obsoleted " + GroupName;
 579                                 change.Append (string.Format ("<span class='obsolete obsolete-{0}' data-is-non-breaking>", ElementName));
 580                                 change.Append ("[Obsolete (");
 581                                 if (tgtObsolete != string.Empty)
 582                                         change.Append ("\"").Append (tgtObsolete).Append ("\"");
 583                                 change.Append (")]\n");
 584                                 change.Append (GetDescription (target));
 585                                 change.Append ("</span>");
 586                                 change.AnyChange = true;
 587                                 changes.Add (source, target, change);
 588                         } else if (tgtObsolete == null) {
 589                                 // Made non-obsolete. Do we care to report this?
 590                         } else {
 591                                 // Obsolete message changed. Do we care to report this?
 592                         }
 593                 }
 594
 595                 protected void RenderName (XElement source, XElement target, ApiChange change)
 596                 {
 597                         var name = target.GetAttribute ("name");
 598                         // show the constructor as it would be defined in C#
 599                         name = name.Replace (".ctor", State.Type);
 600
 601                         var p = name.IndexOf ('(');
 602                         if (p >= 0)
 603                                 name = name.Substring (0, p);
 604
 605                         change.Append (name);
 606                 }
 607
 608         }
 609 }