dom/mathml/MathMLElement.cpp

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/dom/MathMLElement.h"
   8
   9 #include "base/compiler_specific.h"
  10 #include "mozilla/dom/BindContext.h"
  11 #include "mozilla/ArrayUtils.h"
  12 #include "mozilla/EventListenerManager.h"
  13 #include "mozilla/FontPropertyTypes.h"
  14 #include "mozilla/StaticPrefs_mathml.h"
  15 #include "mozilla/TextUtils.h"
  16 #include "nsGkAtoms.h"
  17 #include "nsIContentInlines.h"
  18 #include "nsITableCellLayout.h"  // for MAX_COLSPAN / MAX_ROWSPAN
  19 #include "nsCSSValue.h"
  20 #include "nsStyleConsts.h"
  21 #include "mozilla/dom/Document.h"
  22 #include "nsPresContext.h"
  23 #include "mozAutoDocUpdate.h"
  24 #include "nsIScriptError.h"
  25 #include "nsContentUtils.h"
  26 #include "nsIURI.h"
  27
  28 #include "mozilla/EventDispatcher.h"
  29 #include "mozilla/MappedDeclarationsBuilder.h"
  30 #include "mozilla/dom/MathMLElementBinding.h"
  31
  32 using namespace mozilla;
  33 using namespace mozilla::dom;
  34
  35 //----------------------------------------------------------------------
  36 // nsISupports methods:
  37
  38 NS_IMPL_ISUPPORTS_INHERITED(MathMLElement, MathMLElementBase, Link)
  39
  40 static nsresult ReportLengthParseError(const nsString& aValue,
  41                                        Document* aDocument) {
  42   AutoTArray<nsString, 1> arg = {aValue};
  43   return nsContentUtils::ReportToConsole(
  44       nsIScriptError::errorFlag, "MathML"_ns, aDocument,
  45       nsContentUtils::eMATHML_PROPERTIES, "LengthParsingError", arg);
  46 }
  47
  48 static nsresult ReportParseErrorNoTag(const nsString& aValue, nsAtom* aAtom,
  49                                       Document& aDocument) {
  50   AutoTArray<nsString, 2> argv = {aValue, nsDependentAtomString(aAtom)};
  51   return nsContentUtils::ReportToConsole(
  52       nsIScriptError::errorFlag, "MathML"_ns, &aDocument,
  53       nsContentUtils::eMATHML_PROPERTIES, "AttributeParsingErrorNoTag", argv);
  54 }
  55
  56 MathMLElement::MathMLElement(
  57     already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
  58     : MathMLElementBase(std::move(aNodeInfo)),
  59       ALLOW_THIS_IN_INITIALIZER_LIST(Link(this)) {}
  60
  61 MathMLElement::MathMLElement(
  62     already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
  63     : MathMLElementBase(std::move(aNodeInfo)),
  64       ALLOW_THIS_IN_INITIALIZER_LIST(Link(this)) {}
  65
  66 nsresult MathMLElement::BindToTree(BindContext& aContext, nsINode& aParent) {
  67   nsresult rv = MathMLElementBase::BindToTree(aContext, aParent);
  68   NS_ENSURE_SUCCESS(rv, rv);
  69
  70   Link::BindToTree(aContext);
  71
  72   // Set the bit in the document for telemetry.
  73   if (Document* doc = aContext.GetComposedDoc()) {
  74     doc->SetMathMLEnabled();
  75   }
  76
  77   return rv;
  78 }
  79
  80 void MathMLElement::UnbindFromTree(UnbindContext& aContext) {
  81   MathMLElementBase::UnbindFromTree(aContext);
  82   // Without removing the link state we risk a dangling pointer in the
  83   // mStyledLinks hashtable
  84   Link::UnbindFromTree();
  85 }
  86
  87 bool MathMLElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
  88                                    const nsAString& aValue,
  89                                    nsIPrincipal* aMaybeScriptedPrincipal,
  90                                    nsAttrValue& aResult) {
  91   MOZ_ASSERT(IsMathMLElement());
  92
  93   if (aNamespaceID == kNameSpaceID_None) {
  94     if (aAttribute == nsGkAtoms::color || aAttribute == nsGkAtoms::mathcolor_ ||
  95         aAttribute == nsGkAtoms::background ||
  96         aAttribute == nsGkAtoms::mathbackground_) {
  97       return aResult.ParseColor(aValue);
  98     }
  99     if (aAttribute == nsGkAtoms::tabindex) {
 100       return aResult.ParseIntValue(aValue);
 101     }
 102     if (mNodeInfo->Equals(nsGkAtoms::mtd_)) {
 103       if (aAttribute == nsGkAtoms::columnspan_) {
 104         aResult.ParseClampedNonNegativeInt(aValue, 1, 1, MAX_COLSPAN);
 105         return true;
 106       }
 107       if (aAttribute == nsGkAtoms::rowspan) {
 108         aResult.ParseClampedNonNegativeInt(aValue, 1, 0, MAX_ROWSPAN);
 109         return true;
 110       }
 111     }
 112   }
 113
 114   return MathMLElementBase::ParseAttribute(aNamespaceID, aAttribute, aValue,
 115                                            aMaybeScriptedPrincipal, aResult);
 116 }
 117
 118 // https://mathml-refresh.github.io/mathml-core/#global-attributes
 119 static Element::MappedAttributeEntry sGlobalAttributes[] = {
 120     {nsGkAtoms::dir},
 121     {nsGkAtoms::mathbackground_},
 122     {nsGkAtoms::mathcolor_},
 123     {nsGkAtoms::mathsize_},
 124     {nsGkAtoms::scriptlevel_},
 125     {nsGkAtoms::displaystyle_},
 126     {nullptr}};
 127
 128 bool MathMLElement::IsAttributeMapped(const nsAtom* aAttribute) const {
 129   MOZ_ASSERT(IsMathMLElement());
 130
 131   static const MappedAttributeEntry* const globalMap[] = {sGlobalAttributes};
 132
 133   return FindAttributeDependence(aAttribute, globalMap) ||
 134          ((!StaticPrefs::mathml_legacy_mathvariant_attribute_disabled() ||
 135            mNodeInfo->Equals(nsGkAtoms::mi_)) &&
 136           aAttribute == nsGkAtoms::mathvariant_) ||
 137          (mNodeInfo->Equals(nsGkAtoms::mtable_) &&
 138           aAttribute == nsGkAtoms::width);
 139 }
 140
 141 nsMapRuleToAttributesFunc MathMLElement::GetAttributeMappingFunction() const {
 142   if (mNodeInfo->Equals(nsGkAtoms::mtable_)) {
 143     return &MapMTableAttributesInto;
 144   }
 145   if (StaticPrefs::mathml_legacy_mathvariant_attribute_disabled() &&
 146       mNodeInfo->Equals(nsGkAtoms::mi_)) {
 147     return &MapMiAttributesInto;
 148   }
 149   return &MapGlobalMathMLAttributesInto;
 150 }
 151
 152 /* static */
 153 bool MathMLElement::ParseNamedSpaceValue(const nsString& aString,
 154                                          nsCSSValue& aCSSValue, uint32_t aFlags,
 155                                          const Document& aDocument) {
 156   if (StaticPrefs::mathml_mathspace_names_disabled()) {
 157     return false;
 158   }
 159   int32_t i = 0;
 160   // See if it is one of the 'namedspace' (ranging -7/18em, -6/18, ... 7/18em)
 161   if (aString.EqualsLiteral("veryverythinmathspace")) {
 162     i = 1;
 163   } else if (aString.EqualsLiteral("verythinmathspace")) {
 164     i = 2;
 165   } else if (aString.EqualsLiteral("thinmathspace")) {
 166     i = 3;
 167   } else if (aString.EqualsLiteral("mediummathspace")) {
 168     i = 4;
 169   } else if (aString.EqualsLiteral("thickmathspace")) {
 170     i = 5;
 171   } else if (aString.EqualsLiteral("verythickmathspace")) {
 172     i = 6;
 173   } else if (aString.EqualsLiteral("veryverythickmathspace")) {
 174     i = 7;
 175   } else if (aFlags & PARSE_ALLOW_NEGATIVE) {
 176     if (aString.EqualsLiteral("negativeveryverythinmathspace")) {
 177       i = -1;
 178     } else if (aString.EqualsLiteral("negativeverythinmathspace")) {
 179       i = -2;
 180     } else if (aString.EqualsLiteral("negativethinmathspace")) {
 181       i = -3;
 182     } else if (aString.EqualsLiteral("negativemediummathspace")) {
 183       i = -4;
 184     } else if (aString.EqualsLiteral("negativethickmathspace")) {
 185       i = -5;
 186     } else if (aString.EqualsLiteral("negativeverythickmathspace")) {
 187       i = -6;
 188     } else if (aString.EqualsLiteral("negativeveryverythickmathspace")) {
 189       i = -7;
 190     }
 191   }
 192   if (0 != i) {
 193     AutoTArray<nsString, 1> params;
 194     params.AppendElement(aString);
 195     aDocument.WarnOnceAbout(
 196         dom::DeprecatedOperations::eMathML_DeprecatedMathSpaceValue2, false,
 197         params);
 198     aCSSValue.SetFloatValue(float(i) / float(18), eCSSUnit_EM);
 199     return true;
 200   }
 201
 202   return false;
 203 }
 204
 205 // The REC says:
 206 //
 207 // "Most presentation elements have attributes that accept values representing
 208 // lengths to be used for size, spacing or similar properties. The syntax of a
 209 // length is specified as
 210 //
 211 // number | number unit | namedspace
 212 //
 213 // There should be no space between the number and the unit of a length."
 214 //
 215 // "A trailing '%' represents a percent of the default value. The default
 216 // value, or how it is obtained, is listed in the table of attributes for each
 217 // element. [...] A number without a unit is intepreted as a multiple of the
 218 // default value."
 219 //
 220 // "The possible units in MathML are:
 221 //
 222 // Unit Description
 223 // em   an em (font-relative unit traditionally used for horizontal lengths)
 224 // ex   an ex (font-relative unit traditionally used for vertical lengths)
 225 // px   pixels, or size of a pixel in the current display
 226 // in   inches (1 inch = 2.54 centimeters)
 227 // cm   centimeters
 228 // mm   millimeters
 229 // pt   points (1 point = 1/72 inch)
 230 // pc   picas (1 pica = 12 points)
 231 // %    percentage of default value"
 232 //
 233 // The numbers are defined that way:
 234 // - unsigned-number: "a string of decimal digits with up to one decimal point
 235 //   (U+002E), representing a non-negative terminating decimal number (a type of
 236 //   rational number)"
 237 // - number: "an optional prefix of '-' (U+002D), followed by an unsigned
 238 //   number, representing a terminating decimal number (a type of rational
 239 //   number)"
 240 //
 241 /* static */
 242 // XXXfredw: Deprecate legacy MathML syntax and use the CSS parser instead.
 243 // See https://github.com/mathml-refresh/mathml/issues/63
 244 bool MathMLElement::ParseNumericValue(const nsString& aString,
 245                                       nsCSSValue& aCSSValue, uint32_t aFlags,
 246                                       Document* aDocument) {
 247   nsAutoString str(aString);
 248   str.CompressWhitespace();  // aString is const in this code...
 249
 250   int32_t stringLength = str.Length();
 251   if (!stringLength) {
 252     if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
 253       ReportLengthParseError(aString, aDocument);
 254     }
 255     return false;
 256   }
 257
 258   if (aDocument && ParseNamedSpaceValue(str, aCSSValue, aFlags, *aDocument)) {
 259     return true;
 260   }
 261
 262   nsAutoString number, unit;
 263
 264   // see if the negative sign is there
 265   int32_t i = 0;
 266   char16_t c = str[0];
 267   if (c == '-') {
 268     number.Append(c);
 269     i++;
 270   }
 271
 272   // Gather up characters that make up the number
 273   bool gotDot = false;
 274   for (; i < stringLength; i++) {
 275     c = str[i];
 276     if (gotDot && c == '.') {
 277       if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
 278         ReportLengthParseError(aString, aDocument);
 279       }
 280       return false;  // two dots encountered
 281     } else if (c == '.')
 282       gotDot = true;
 283     else if (!IsAsciiDigit(c)) {
 284       str.Right(unit, stringLength - i);
 285       // some authors leave blanks before the unit, but that shouldn't
 286       // be allowed, so don't CompressWhitespace on 'unit'.
 287       break;
 288     }
 289     number.Append(c);
 290   }
 291   if (gotDot && str[i - 1] == '.') {
 292     if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
 293       ReportLengthParseError(aString, aDocument);
 294     }
 295     return false;  // Number ending with a dot.
 296   }
 297
 298   // Convert number to floating point
 299   nsresult errorCode;
 300   float floatValue = number.ToFloat(&errorCode);
 301   if (NS_FAILED(errorCode)) {
 302     if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
 303       ReportLengthParseError(aString, aDocument);
 304     }
 305     return false;
 306   }
 307   if (floatValue < 0 && !(aFlags & PARSE_ALLOW_NEGATIVE)) {
 308     if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
 309       ReportLengthParseError(aString, aDocument);
 310     }
 311     return false;
 312   }
 313
 314   nsCSSUnit cssUnit;
 315   if (unit.IsEmpty()) {
 316     // We are supposed to have a unit, but there isn't one.
 317     // If the value is 0 we can just call it "pixels" otherwise
 318     // this is illegal.
 319     if (floatValue != 0.0) {
 320       if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
 321         ReportLengthParseError(aString, aDocument);
 322       }
 323       return false;
 324     }
 325     cssUnit = eCSSUnit_Pixel;
 326   } else if (unit.EqualsLiteral("%")) {
 327     aCSSValue.SetPercentValue(floatValue / 100.0f);
 328     return true;
 329   } else if (unit.LowerCaseEqualsLiteral("em"))
 330     cssUnit = eCSSUnit_EM;
 331   else if (unit.LowerCaseEqualsLiteral("ex"))
 332     cssUnit = eCSSUnit_XHeight;
 333   else if (unit.LowerCaseEqualsLiteral("px"))
 334     cssUnit = eCSSUnit_Pixel;
 335   else if (unit.LowerCaseEqualsLiteral("in"))
 336     cssUnit = eCSSUnit_Inch;
 337   else if (unit.LowerCaseEqualsLiteral("cm"))
 338     cssUnit = eCSSUnit_Centimeter;
 339   else if (unit.LowerCaseEqualsLiteral("mm"))
 340     cssUnit = eCSSUnit_Millimeter;
 341   else if (unit.LowerCaseEqualsLiteral("pt"))
 342     cssUnit = eCSSUnit_Point;
 343   else if (unit.LowerCaseEqualsLiteral("pc"))
 344     cssUnit = eCSSUnit_Pica;
 345   else if (unit.LowerCaseEqualsLiteral("q"))
 346     cssUnit = eCSSUnit_Quarter;
 347   else {  // unexpected unit
 348     if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
 349       ReportLengthParseError(aString, aDocument);
 350     }
 351     return false;
 352   }
 353
 354   aCSSValue.SetFloatValue(floatValue, cssUnit);
 355   return true;
 356 }
 357
 358 void MathMLElement::MapMTableAttributesInto(
 359     MappedDeclarationsBuilder& aBuilder) {
 360   // width
 361   //
 362   // "Specifies the desired width of the entire table and is intended for
 363   // visual user agents. When the value is a percentage value, the value is
 364   // relative to the horizontal space a MathML renderer has available for the
 365   // math element. When the value is "auto", the MathML renderer should
 366   // calculate the table width from its contents using whatever layout
 367   // algorithm it chooses. "
 368   //
 369   // values: "auto" | length
 370   // default: auto
 371   //
 372   if (!aBuilder.PropertyIsSet(eCSSProperty_width)) {
 373     const nsAttrValue* value = aBuilder.GetAttr(nsGkAtoms::width);
 374     nsCSSValue width;
 375     // This does not handle auto and unitless values
 376     if (value && value->Type() == nsAttrValue::eString) {
 377       ParseNumericValue(value->GetStringValue(), width, 0,
 378                         &aBuilder.Document());
 379       if (width.GetUnit() == eCSSUnit_Percent) {
 380         aBuilder.SetPercentValue(eCSSProperty_width, width.GetPercentValue());
 381       } else if (width.GetUnit() != eCSSUnit_Null) {
 382         aBuilder.SetLengthValue(eCSSProperty_width, width);
 383       }
 384     }
 385   }
 386   MapGlobalMathMLAttributesInto(aBuilder);
 387 }
 388
 389 void MathMLElement::MapMiAttributesInto(MappedDeclarationsBuilder& aBuilder) {
 390   // mathvariant
 391   // https://w3c.github.io/mathml-core/#dfn-mathvariant
 392   if (!aBuilder.PropertyIsSet(eCSSProperty_text_transform)) {
 393     const nsAttrValue* value = aBuilder.GetAttr(nsGkAtoms::mathvariant_);
 394     if (value && value->Type() == nsAttrValue::eString) {
 395       auto str = value->GetStringValue();
 396       str.CompressWhitespace();
 397       if (value->GetStringValue().LowerCaseEqualsASCII("normal")) {
 398         aBuilder.SetKeywordValue(eCSSProperty_text_transform,
 399                                  StyleTextTransformCase::None);
 400       }
 401     }
 402   }
 403   MapGlobalMathMLAttributesInto(aBuilder);
 404 }
 405
 406 void MathMLElement::MapGlobalMathMLAttributesInto(
 407     MappedDeclarationsBuilder& aBuilder) {
 408   // scriptlevel
 409   // https://w3c.github.io/mathml-core/#dfn-scriptlevel
 410   const nsAttrValue* value = aBuilder.GetAttr(nsGkAtoms::scriptlevel_);
 411   if (value && value->Type() == nsAttrValue::eString &&
 412       !aBuilder.PropertyIsSet(eCSSProperty_math_depth)) {
 413     auto str = value->GetStringValue();
 414     // FIXME: Should we remove whitespace trimming?
 415     // See https://github.com/w3c/mathml/issues/122
 416     str.CompressWhitespace();
 417     if (str.Length() > 0) {
 418       nsresult errorCode;
 419       int32_t intValue = str.ToInteger(&errorCode);
 420       bool reportParseError = true;
 421       if (NS_SUCCEEDED(errorCode)) {
 422         char16_t ch = str.CharAt(0);
 423         bool isRelativeScriptLevel = (ch == '+' || ch == '-');
 424         // ToInteger is not very strict, check this is really <unsigned>.
 425         reportParseError = false;
 426         for (uint32_t i = isRelativeScriptLevel ? 1 : 0; i < str.Length();
 427              i++) {
 428           if (!IsAsciiDigit(str.CharAt(i))) {
 429             reportParseError = true;
 430             break;
 431           }
 432         }
 433         if (!reportParseError) {
 434           aBuilder.SetMathDepthValue(intValue, isRelativeScriptLevel);
 435         }
 436       }
 437       if (reportParseError) {
 438         ReportParseErrorNoTag(str, nsGkAtoms::scriptlevel_,
 439                               aBuilder.Document());
 440       }
 441     }
 442   }
 443
 444   // mathsize
 445   // https://w3c.github.io/mathml-core/#dfn-mathsize
 446   value = aBuilder.GetAttr(nsGkAtoms::mathsize_);
 447   if (value && value->Type() == nsAttrValue::eString &&
 448       !aBuilder.PropertyIsSet(eCSSProperty_font_size)) {
 449     auto str = value->GetStringValue();
 450     nsCSSValue fontSize;
 451     ParseNumericValue(str, fontSize, 0, nullptr);
 452     if (fontSize.GetUnit() == eCSSUnit_Percent) {
 453       aBuilder.SetPercentValue(eCSSProperty_font_size,
 454                                fontSize.GetPercentValue());
 455     } else if (fontSize.GetUnit() != eCSSUnit_Null) {
 456       aBuilder.SetLengthValue(eCSSProperty_font_size, fontSize);
 457     }
 458   }
 459
 460   if (!StaticPrefs::mathml_legacy_mathvariant_attribute_disabled()) {
 461     // mathvariant
 462     //
 463     // "Specifies the logical class of the token. Note that this class is more
 464     // than styling, it typically conveys semantic intent;"
 465     //
 466     // values: "normal" | "bold" | "italic" | "bold-italic" | "double-struck" |
 467     // "bold-fraktur" | "script" | "bold-script" | "fraktur" | "sans-serif" |
 468     // "bold-sans-serif" | "sans-serif-italic" | "sans-serif-bold-italic" |
 469     // "monospace" | "initial" | "tailed" | "looped" | "stretched"
 470     // default: normal (except on <mi>)
 471     //
 472     value = aBuilder.GetAttr(nsGkAtoms::mathvariant_);
 473     if (value && value->Type() == nsAttrValue::eString &&
 474         !aBuilder.PropertyIsSet(eCSSProperty__moz_math_variant)) {
 475       auto str = value->GetStringValue();
 476       str.CompressWhitespace();
 477       static const char sizes[19][23] = {"normal",
 478                                          "bold",
 479                                          "italic",
 480                                          "bold-italic",
 481                                          "script",
 482                                          "bold-script",
 483                                          "fraktur",
 484                                          "double-struck",
 485                                          "bold-fraktur",
 486                                          "sans-serif",
 487                                          "bold-sans-serif",
 488                                          "sans-serif-italic",
 489                                          "sans-serif-bold-italic",
 490                                          "monospace",
 491                                          "initial",
 492                                          "tailed",
 493                                          "looped",
 494                                          "stretched"};
 495       static const StyleMathVariant values[MOZ_ARRAY_LENGTH(sizes)] = {
 496           StyleMathVariant::Normal,
 497           StyleMathVariant::Bold,
 498           StyleMathVariant::Italic,
 499           StyleMathVariant::BoldItalic,
 500           StyleMathVariant::Script,
 501           StyleMathVariant::BoldScript,
 502           StyleMathVariant::Fraktur,
 503           StyleMathVariant::DoubleStruck,
 504           StyleMathVariant::BoldFraktur,
 505           StyleMathVariant::SansSerif,
 506           StyleMathVariant::BoldSansSerif,
 507           StyleMathVariant::SansSerifItalic,
 508           StyleMathVariant::SansSerifBoldItalic,
 509           StyleMathVariant::Monospace,
 510           StyleMathVariant::Initial,
 511           StyleMathVariant::Tailed,
 512           StyleMathVariant::Looped,
 513           StyleMathVariant::Stretched};
 514       for (uint32_t i = 0; i < ArrayLength(sizes); ++i) {
 515         if (str.LowerCaseEqualsASCII(sizes[i])) {
 516           if (values[i] != StyleMathVariant::Normal) {
 517             // Warn about deprecated mathvariant attribute values. Strictly
 518             // speaking, we should also warn about mathvariant="normal" if the
 519             // element is not an <mi>. However this would require exposing the
 520             // tag name via aBuilder. Moreover, this use case is actually to
 521             // revert the effect of a non-normal mathvariant value on an
 522             // ancestor element, which should consequently have already
 523             // triggered a warning.
 524             AutoTArray<nsString, 1> params;
 525             params.AppendElement(str);
 526             aBuilder.Document().WarnOnceAbout(
 527                 dom::DeprecatedOperations::eMathML_DeprecatedMathVariant, false,
 528                 params);
 529           }
 530           aBuilder.SetKeywordValue(eCSSProperty__moz_math_variant, values[i]);
 531           break;
 532         }
 533       }
 534     }
 535   }
 536
 537   // mathbackground
 538   // https://w3c.github.io/mathml-core/#dfn-mathbackground
 539   value = aBuilder.GetAttr(nsGkAtoms::mathbackground_);
 540   if (value) {
 541     nscolor color;
 542     if (value->GetColorValue(color)) {
 543       aBuilder.SetColorValueIfUnset(eCSSProperty_background_color, color);
 544     }
 545   }
 546
 547   // mathcolor
 548   // https://w3c.github.io/mathml-core/#dfn-mathcolor
 549   value = aBuilder.GetAttr(nsGkAtoms::mathcolor_);
 550   nscolor color;
 551   if (value && value->GetColorValue(color)) {
 552     aBuilder.SetColorValueIfUnset(eCSSProperty_color, color);
 553   }
 554
 555   // dir
 556   // https://w3c.github.io/mathml-core/#dfn-dir
 557   value = aBuilder.GetAttr(nsGkAtoms::dir);
 558   if (value && value->Type() == nsAttrValue::eString &&
 559       !aBuilder.PropertyIsSet(eCSSProperty_direction)) {
 560     auto str = value->GetStringValue();
 561     static const char dirs[][4] = {"ltr", "rtl"};
 562     static const StyleDirection dirValues[MOZ_ARRAY_LENGTH(dirs)] = {
 563         StyleDirection::Ltr, StyleDirection::Rtl};
 564     for (uint32_t i = 0; i < ArrayLength(dirs); ++i) {
 565       if (str.LowerCaseEqualsASCII(dirs[i])) {
 566         aBuilder.SetKeywordValue(eCSSProperty_direction, dirValues[i]);
 567         break;
 568       }
 569     }
 570   }
 571
 572   // displaystyle
 573   // https://mathml-refresh.github.io/mathml-core/#dfn-displaystyle
 574   value = aBuilder.GetAttr(nsGkAtoms::displaystyle_);
 575   if (value && value->Type() == nsAttrValue::eString &&
 576       !aBuilder.PropertyIsSet(eCSSProperty_math_style)) {
 577     auto str = value->GetStringValue();
 578     static const char displaystyles[][6] = {"false", "true"};
 579     static const StyleMathStyle mathStyle[MOZ_ARRAY_LENGTH(displaystyles)] = {
 580         StyleMathStyle::Compact, StyleMathStyle::Normal};
 581     for (uint32_t i = 0; i < ArrayLength(displaystyles); ++i) {
 582       if (str.LowerCaseEqualsASCII(displaystyles[i])) {
 583         aBuilder.SetKeywordValue(eCSSProperty_math_style, mathStyle[i]);
 584         break;
 585       }
 586     }
 587   }
 588 }
 589
 590 void MathMLElement::GetEventTargetParent(EventChainPreVisitor& aVisitor) {
 591   Element::GetEventTargetParent(aVisitor);
 592
 593   GetEventTargetParentForLinks(aVisitor);
 594 }
 595
 596 nsresult MathMLElement::PostHandleEvent(EventChainPostVisitor& aVisitor) {
 597   return PostHandleEventForLinks(aVisitor);
 598 }
 599
 600 NS_IMPL_ELEMENT_CLONE(MathMLElement)
 601
 602 void MathMLElement::SetIncrementScriptLevel(bool aIncrementScriptLevel,
 603                                             bool aNotify) {
 604   NS_ASSERTION(aNotify, "We always notify!");
 605   if (aIncrementScriptLevel) {
 606     AddStates(ElementState::INCREMENT_SCRIPT_LEVEL);
 607   } else {
 608     RemoveStates(ElementState::INCREMENT_SCRIPT_LEVEL);
 609   }
 610 }
 611
 612 int32_t MathMLElement::TabIndexDefault() { return IsLink() ? 0 : -1; }
 613
 614 // XXX Bug 1586011: Share logic with other element classes.
 615 Focusable MathMLElement::IsFocusableWithoutStyle(bool aWithMouse) {
 616   if (!IsInComposedDoc() || IsInDesignMode()) {
 617     // In designMode documents we only allow focusing the document.
 618     return {};
 619   }
 620
 621   int32_t tabIndex = TabIndex();
 622   if (!IsLink()) {
 623     // If a tabindex is specified at all we're focusable
 624     if (GetTabIndexAttrValue().isSome()) {
 625       return {true, tabIndex};
 626     }
 627     return {};
 628   }
 629
 630   if (!OwnerDoc()->LinkHandlingEnabled()) {
 631     return {};
 632   }
 633
 634   // Links that are in an editable region should never be focusable, even if
 635   // they are in a contenteditable="false" region.
 636   if (nsContentUtils::IsNodeInEditableRegion(this)) {
 637     return {};
 638   }
 639
 640   if ((sTabFocusModel & eTabFocus_linksMask) == 0) {
 641     tabIndex = -1;
 642   }
 643
 644   return {true, tabIndex};
 645 }
 646
 647 already_AddRefed<nsIURI> MathMLElement::GetHrefURI() const {
 648   // MathML href
 649   // The REC says: "When user agents encounter MathML elements with both href
 650   // and xlink:href attributes, the href attribute should take precedence."
 651   const nsAttrValue* href = mAttrs.GetAttr(nsGkAtoms::href, kNameSpaceID_None);
 652   if (!href) {
 653     return nullptr;
 654   }
 655   // Get absolute URI
 656   nsAutoString hrefStr;
 657   href->ToString(hrefStr);
 658   nsCOMPtr<nsIURI> hrefURI;
 659   nsContentUtils::NewURIWithDocumentCharset(getter_AddRefs(hrefURI), hrefStr,
 660                                             OwnerDoc(), GetBaseURI());
 661   return hrefURI.forget();
 662 }
 663
 664 bool MathMLElement::IsEventAttributeNameInternal(nsAtom* aName) {
 665   // The intent is to align MathML event attributes on HTML5, so the flag
 666   // EventNameType_HTML is used here.
 667   return nsContentUtils::IsEventAttributeName(aName, EventNameType_HTML);
 668 }
 669
 670 void MathMLElement::BeforeSetAttr(int32_t aNamespaceID, nsAtom* aName,
 671                                   const nsAttrValue* aValue, bool aNotify) {
 672   if (aNamespaceID == kNameSpaceID_None) {
 673     if (!aValue && IsEventAttributeName(aName)) {
 674       if (EventListenerManager* manager = GetExistingListenerManager()) {
 675         manager->RemoveEventHandler(GetEventNameForAttr(aName));
 676       }
 677     }
 678   }
 679
 680   return MathMLElementBase::BeforeSetAttr(aNamespaceID, aName, aValue, aNotify);
 681 }
 682
 683 void MathMLElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
 684                                  const nsAttrValue* aValue,
 685                                  const nsAttrValue* aOldValue,
 686                                  nsIPrincipal* aSubjectPrincipal,
 687                                  bool aNotify) {
 688   // It is important that this be done after the attribute is set/unset.
 689   // We will need the updated attribute value because notifying the document
 690   // that content states have changed will call IntrinsicState, which will try
 691   // to get updated information about the visitedness from Link.
 692   if (aName == nsGkAtoms::href && aNameSpaceID == kNameSpaceID_None) {
 693     Link::ResetLinkState(aNotify, aValue || Link::ElementHasHref());
 694   }
 695
 696   if (aNameSpaceID == kNameSpaceID_None) {
 697     if (IsEventAttributeName(aName) && aValue) {
 698       MOZ_ASSERT(aValue->Type() == nsAttrValue::eString,
 699                  "Expected string value for script body");
 700       SetEventHandler(GetEventNameForAttr(aName), aValue->GetStringValue());
 701     }
 702   }
 703
 704   return MathMLElementBase::AfterSetAttr(aNameSpaceID, aName, aValue, aOldValue,
 705                                          aSubjectPrincipal, aNotify);
 706 }
 707
 708 JSObject* MathMLElement::WrapNode(JSContext* aCx,
 709                                   JS::Handle<JSObject*> aGivenProto) {
 710   return MathMLElement_Binding::Wrap(aCx, this, aGivenProto);
 711 }