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, false);
 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                         Output.WriteLine ("<div>");
 203                         Output.WriteLine ("<p>Added {0}:</p>", list.Count () > 1 ? GroupName : ElementName);
 204                         Output.WriteLine ("<pre>");
 205                 }
 206
 207                 public override void Added (XElement target, bool wasParentAdded)
 208                 {
 209                         var o = GetObsoleteMessage (target);
 210                         if (!first && (o.Length > 0))
 211                                 Output.WriteLine ();
 212                         Indent ();
 213                         bool isInterfaceBreakingChange = !wasParentAdded && IsInInterface (target);
 214                         Output.Write ("\t<span class='added added-{0} {1}' {2}>", ElementName, isInterfaceBreakingChange ? "breaking" : string.Empty, isInterfaceBreakingChange ? "data-is-breaking" : "data-is-non-breaking");
 215                         Output.Write ("{0}{1}", o, GetDescription (target));
 216                         Output.WriteLine ("</span>");
 217                         first = false;
 218                 }
 219
 220                 public virtual void AfterAdding ()
 221                 {
 222                         Output.WriteLine ("</pre>");
 223                         Output.WriteLine ("</div>");
 224                 }
 225
 226                 public override void Modified (XElement source, XElement target, ApiChanges change)
 227                 {
 228                 }
 229
 230                 public virtual void BeforeRemoving (IEnumerable<XElement> list)
 231                 {
 232                         first = true;
 233                         Output.WriteLine ("<p>Removed {0}:</p>\n", list.Count () > 1 ? GroupName : ElementName);
 234                         Output.WriteLine ("<pre>");
 235                 }
 236
 237                 public override void Removed (XElement source)
 238                 {
 239                         var o = GetObsoleteMessage (source);
 240                         if (!first && (o.Length > 0))
 241                                 Output.WriteLine ();
 242
 243                         bool is_breaking = IsBreakingRemoval (source);
 244
 245                         Indent ();
 246                         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);
 247                         Output.Write ("{0}{1}", o, GetDescription (source));
 248                         Output.WriteLine ("</span>");
 249                         first = false;
 250                 }
 251
 252                 public virtual void AfterRemoving ()
 253                 {
 254                         Output.WriteLine ("</pre>");;
 255                 }
 256
 257                 string RenderGenericParameter (XElement gp)
 258                 {
 259                         var sb = new StringBuilder ();
 260                         sb.Append (gp.GetTypeName ("name"));
 261
 262                         var constraints = gp.DescendantList ("generic-parameter-constraints", "generic-parameter-constraint");
 263                         if (constraints != null && constraints.Count > 0) {
 264                                 sb.Append (" : ");
 265                                 for (int i = 0; i < constraints.Count; i++) {
 266                                         if (i > 0)
 267                                                 sb.Append (", ");
 268                                         sb.Append (constraints [i].GetTypeName ("name"));
 269                                 }
 270                         }
 271                         return sb.ToString ();
 272                 }
 273
 274                 protected void RenderGenericParameters (XElement source, XElement target, ApiChange change)
 275                 {
 276                         var src = source.DescendantList ("generic-parameters", "generic-parameter");
 277                         var tgt = target.DescendantList ("generic-parameters", "generic-parameter");
 278                         var srcCount = src == null ? 0 : src.Count;
 279                         var tgtCount = tgt == null ? 0 : tgt.Count;
 280
 281                         if (srcCount == 0 && tgtCount == 0)
 282                                 return;
 283
 284                         change.Append ("&lt;");
 285                         for (int i = 0; i < Math.Max (srcCount, tgtCount); i++) {
 286                                 if (i > 0)
 287                                         change.Append (", ");
 288                                 if (i >= srcCount) {
 289                                         change.AppendAdded (RenderGenericParameter (tgt [i]), true);
 290                                 } else if (i >= tgtCount) {
 291                                         change.AppendRemoved (RenderGenericParameter (src [i]), true);
 292                                 } else {
 293                                         var srcName = RenderGenericParameter (src [i]);
 294                                         var tgtName = RenderGenericParameter (tgt [i]);
 295
 296                                         if (srcName != tgtName) {
 297                                                 change.AppendModified (srcName, tgtName, true);
 298                                         } else {
 299                                                 change.Append (srcName);
 300                                         }
 301                                         }
 302                                 }
 303                         change.Append ("&gt;");
 304                 }
 305
 306                 protected string FormatValue (string type, string value)
 307                 {
 308                         if (value == null)
 309                                 return "null";
 310
 311                         if (type == "string")
 312                                 return "\"" + value + "\"";
 313                         else if (type == "bool") {
 314                                 switch (value) {
 315                                 case "True":
 316                                         return "true";
 317                                 case "False":
 318                                         return "false";
 319                                 default:
 320                                         return value;
 321                                 }
 322                         }
 323
 324                         return value;
 325                 }
 326
 327                 protected void RenderParameters (XElement source, XElement target, ApiChange change)
 328                 {
 329                         var src = source.DescendantList ("parameters", "parameter");
 330                         var tgt = target.DescendantList ("parameters", "parameter");
 331                         var srcCount = src == null ? 0 : src.Count;
 332                         var tgtCount = tgt == null ? 0 : tgt.Count;
 333
 334                         change.Append (" (");
 335                         for (int i = 0; i < Math.Max (srcCount, tgtCount); i++) {
 336                                 if (i > 0)
 337                                         change.Append (", ");
 338
 339                                 if (i >= srcCount) {
 340                                         change.AppendAdded (tgt [i].GetTypeName ("type") + " " + tgt [i].GetAttribute ("name"), true);
 341                                 } else if (i >= tgtCount) {
 342                                         change.AppendRemoved (src [i].GetTypeName ("type") + " " + src [i].GetAttribute ("name"), true);
 343                                 } else {
 344                                         var paramSourceType = src [i].GetTypeName ("type");
 345                                         var paramTargetType = tgt [i].GetTypeName ("type");
 346
 347                                         var paramSourceName = src [i].GetAttribute ("name");
 348                                         var paramTargetName = tgt [i].GetAttribute ("name");
 349
 350                                         if (paramSourceType != paramTargetType) {
 351                                                 change.AppendModified (paramSourceType, paramTargetType, true);
 352                                         } else {
 353                                                 change.Append (paramSourceType);
 354                                         }
 355                                         change.Append (" ");
 356                                         if (paramSourceName != paramTargetName) {
 357                                                 change.AppendModified (paramSourceName, paramTargetName, false);
 358                                         } else {
 359                                                 change.Append (paramSourceName);
 360                                         }
 361
 362                                         var optSource = src [i].Attribute ("optional");
 363                                         var optTarget = tgt [i].Attribute ("optional");
 364                                         var srcValue = FormatValue (paramSourceType, src [i].GetAttribute ("defaultValue"));
 365                                         var tgtValue = FormatValue (paramTargetType, tgt [i].GetAttribute ("defaultValue"));
 366
 367                                         if (optSource != null) {
 368                                                 if (optTarget != null) {
 369                                                         change.Append (" = ");
 370                                                         if (srcValue != tgtValue) {
 371                                                                 change.AppendModified (srcValue, tgtValue, false);
 372                                                         } else {
 373                                                                 change.Append (tgtValue);
 374                                                         }
 375                                                 } else {
 376                                                         change.AppendRemoved (" = " + srcValue);
 377                                                 }
 378                                         } else {
 379                                                 if (optTarget != null)
 380                                                         change.AppendAdded (" = " + tgtValue);
 381                                         }
 382                                 }
 383                         }
 384
 385                         change.Append (")");
 386
 387                         // Ignore any parameter name changes if requested.
 388                         if (State.IgnoreParameterNameChanges && !change.Breaking) {
 389                                 change.AnyChange = false;
 390                                 change.HasIgnoredChanges = true;
 391                         }
 392                 }
 393
 394                 void RenderVTable (MethodAttributes source, MethodAttributes target, ApiChange change)
 395                 {
 396                         var srcAbstract = (source & MethodAttributes.Abstract) == MethodAttributes.Abstract;
 397                         var tgtAbstract = (target & MethodAttributes.Abstract) == MethodAttributes.Abstract;
 398                         var srcFinal = (source & MethodAttributes.Final) == MethodAttributes.Final;
 399                         var tgtFinal = (target & MethodAttributes.Final) == MethodAttributes.Final;
 400                         var srcVirtual = (source & MethodAttributes.Virtual) == MethodAttributes.Virtual;
 401                         var tgtVirtual = (target & MethodAttributes.Virtual) == MethodAttributes.Virtual;
 402                         var srcOverride = (source & MethodAttributes.VtableLayoutMask) != MethodAttributes.NewSlot;
 403                         var tgtOverride = (target & MethodAttributes.VtableLayoutMask) != MethodAttributes.NewSlot;
 404
 405                         var srcWord = srcVirtual ? (srcOverride ? "override" : "virtual") : string.Empty;
 406                         var tgtWord = tgtVirtual ? (tgtOverride ? "override" : "virtual") : string.Empty;
 407                         var breaking = srcWord.Length > 0 && tgtWord.Length == 0;
 408
 409                         if (srcAbstract) {
 410                                 if (tgtAbstract) {
 411                                         change.Append ("abstract ");
 412                                 } else if (tgtVirtual) {
 413                                         change.AppendModified ("abstract", tgtWord, false).Append (" ");
 414                                 } else {
 415                                         change.AppendRemoved ("abstract").Append (" ");
 416                                 }
 417                         } else {
 418                                 if (tgtAbstract) {
 419                                         change.AppendAdded ("abstract", true).Append (" ");
 420                                 } else if (srcWord != tgtWord) {
 421                                         if (!tgtFinal)
 422                                                 change.AppendModified (srcWord, tgtWord, breaking).Append (" ");
 423                                 } else if (tgtWord.Length > 0) {
 424                                         change.Append (tgtWord).Append (" ");
 425                                 } else if (srcWord.Length > 0) {
 426                                         change.AppendRemoved (srcWord, breaking).Append (" ");
 427                                 }
 428                         }
 429
 430                         if (srcFinal) {
 431                                 if (tgtFinal) {
 432                                         change.Append ("final ");
 433                                 } else {
 434                                         change.AppendRemoved ("final", false).Append (" "); // removing 'final' is not a breaking change.
 435                                 }
 436                         } else {
 437                                 if (tgtFinal && srcVirtual) {
 438                                         change.AppendModified ("virtual", "final", true).Append (" "); // adding 'final' is a breaking change if the member was virtual
 439                                 }
 440                         }
 441
 442                         if (!srcVirtual && !srcFinal && tgtVirtual && tgtFinal) {
 443                                 // existing member implements a member from a new interface
 444                                 // this would show up as 'virtual final', which is redundant, so show nothing at all.
 445                                 change.HasIgnoredChanges = true;
 446                         }
 447
 448                         // Ignore non-breaking virtual changes.
 449                         if (State.IgnoreVirtualChanges && !change.Breaking) {
 450                                 change.AnyChange = false;
 451                                 change.HasIgnoredChanges = true;
 452                         }
 453
 454                         var tgtSecurity = (source & MethodAttributes.HasSecurity) == MethodAttributes.HasSecurity;
 455                         var srcSecurity = (target & MethodAttributes.HasSecurity) == MethodAttributes.HasSecurity;
 456
 457                         if (tgtSecurity != srcSecurity)
 458                                 change.HasIgnoredChanges = true;
 459
 460                         var srcPInvoke = (source & MethodAttributes.PinvokeImpl) == MethodAttributes.PinvokeImpl;
 461                         var tgtPInvoke = (target & MethodAttributes.PinvokeImpl) == MethodAttributes.PinvokeImpl;
 462                         if (srcPInvoke != tgtPInvoke)
 463                                 change.HasIgnoredChanges = true;
 464                 }
 465
 466                 protected string GetVisibility (MethodAttributes attr)
 467                 {
 468                         switch (attr) {
 469                         case MethodAttributes.Private:
 470                         case MethodAttributes.PrivateScope:
 471                                 return "private";
 472                         case MethodAttributes.Assembly:
 473                                 return "internal";
 474                         case MethodAttributes.FamANDAssem:
 475                                 return "private internal";
 476                         case MethodAttributes.FamORAssem:
 477                                 return "protected"; // customers don't care about 'internal';
 478                         case MethodAttributes.Family:
 479                                 return "protected";
 480                         case MethodAttributes.Public:
 481                                 return "public";
 482                         default:
 483                                 throw new NotImplementedException ();
 484                         }
 485                 }
 486
 487                 protected void RenderVisibility (MethodAttributes source, MethodAttributes target, ApiChange diff)
 488                 {
 489                         source = source & MethodAttributes.MemberAccessMask;
 490                         target = target & MethodAttributes.MemberAccessMask;
 491
 492                         if (source == target) {
 493                                 diff.Append (GetVisibility (target));
 494                         } else {
 495                                 var breaking = false;
 496                                 switch (source) {
 497                                 case MethodAttributes.Private:
 498                                 case MethodAttributes.Assembly:
 499                                 case MethodAttributes.FamANDAssem:
 500                                         break; // these are not publicly visible, thus not breaking
 501                                 case MethodAttributes.FamORAssem:
 502                                 case MethodAttributes.Family:
 503                                         switch (target) {
 504                                         case MethodAttributes.Public:
 505                                                 // to public is not a breaking change
 506                                                 break;
 507                                         case MethodAttributes.Family:
 508                                         case MethodAttributes.FamORAssem:
 509                                                 // not a breaking change, but should still show up in diff
 510                                                 break;
 511                                         default:
 512                                                 // anything else is a breaking change
 513                                                 breaking = true;
 514                                                 break;
 515                                         }
 516                                         break;
 517                                 case MethodAttributes.Public:
 518                                 default:
 519                                         // any change from public is breaking.
 520                                         breaking = true;
 521                                         break;
 522                                 }
 523
 524                                 diff.AppendModified (GetVisibility (source), GetVisibility (target), breaking);
 525                         }
 526                         diff.Append (" ");
 527                 }
 528
 529                 protected void RenderStatic (MethodAttributes src, MethodAttributes tgt, ApiChange diff)
 530                 {
 531                         var srcStatic = (src & MethodAttributes.Static) == MethodAttributes.Static;
 532                         var tgtStatic = (tgt & MethodAttributes.Static) == MethodAttributes.Static;
 533
 534                         if (srcStatic != tgtStatic) {
 535                                 if (srcStatic) {
 536                                         diff.AppendRemoved ("static", true).Append (" ");
 537                                 } else {
 538                                         diff.AppendAdded ("static", true).Append (" ");
 539                                 }
 540                         }
 541                 }
 542
 543                 protected void RenderMethodAttributes (MethodAttributes src, MethodAttributes tgt, ApiChange diff)
 544                 {
 545                         RenderStatic (src, tgt, diff);
 546                         RenderVisibility (src & MethodAttributes.MemberAccessMask, tgt & MethodAttributes.MemberAccessMask, diff);
 547                         RenderVTable (src, tgt, diff);
 548                 }
 549
 550                 protected void RenderMethodAttributes (XElement source, XElement target, ApiChange diff)
 551                 {
 552                         RenderMethodAttributes (source.GetMethodAttributes (), target.GetMethodAttributes (), diff);
 553                 }
 554
 555                 protected void RemoveAttributes (XElement element)
 556                 {
 557                         var srcAttributes = element.Element ("attributes");
 558                         if (srcAttributes != null)
 559                                 srcAttributes.Remove ();
 560
 561                         foreach (var el in element.Elements ())
 562                                 RemoveAttributes (el);
 563                 }
 564
 565                 protected void RenderAttributes (XElement source, XElement target, ApiChanges changes)
 566                 {
 567                         var srcObsolete = source.GetObsoleteMessage ();
 568                         var tgtObsolete = target.GetObsoleteMessage ();
 569
 570                         if (srcObsolete == tgtObsolete)
 571                                 return; // nothing changed
 572
 573                         if (srcObsolete == null) {
 574                                 if (tgtObsolete == null)
 575                                         return; // neither is obsolete
 576                                 var change = new ApiChange ();
 577                                 change.Header = "Obsoleted " + GroupName;
 578                                 change.Append (string.Format ("<span class='obsolete obsolete-{0}' data-is-non-breaking>", ElementName));
 579                                 change.Append ("[Obsolete (");
 580                                 if (tgtObsolete != string.Empty)
 581                                         change.Append ("\"").Append (tgtObsolete).Append ("\"");
 582                                 change.Append (")]\n");
 583                                 change.Append (GetDescription (target));
 584                                 change.Append ("</span>");
 585                                 change.AnyChange = true;
 586                                 changes.Add (source, target, change);
 587                         } else if (tgtObsolete == null) {
 588                                 // Made non-obsolete. Do we care to report this?
 589                         } else {
 590                                 // Obsolete message changed. Do we care to report this?
 591                         }
 592                 }
 593
 594                 protected void RenderName (XElement source, XElement target, ApiChange change)
 595                 {
 596                         var name = target.GetAttribute ("name");
 597                         // show the constructor as it would be defined in C#
 598                         name = name.Replace (".ctor", State.Type);
 599
 600                         var p = name.IndexOf ('(');
 601                         if (p >= 0)
 602                                 name = name.Substring (0, p);
 603
 604                         change.Append (name);
 605                 }
 606
 607         }
 608 }