summaryrefslogtreecommitdiffstats
path: root/dom/script/ScriptElement.cpp
blob: d242888ce3f8b52a7cfb1af5e7f30b20826c7b7e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "ScriptElement.h"
#include "ScriptLoader.h"
#include "mozilla/BasicEvents.h"
#include "mozilla/CycleCollectedJSContext.h"
#include "mozilla/EventDispatcher.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/Element.h"
#include "mozilla/dom/MutationEventBinding.h"
#include "nsContentUtils.h"
#include "nsThreadUtils.h"
#include "nsPresContext.h"
#include "nsIParser.h"
#include "nsGkAtoms.h"
#include "nsContentSink.h"

using namespace mozilla;
using namespace mozilla::dom;

NS_IMETHODIMP
ScriptElement::ScriptAvailable(nsresult aResult, nsIScriptElement* aElement,
                               bool aIsInlineClassicScript, nsIURI* aURI,
                               uint32_t aLineNo) {
  if (!aIsInlineClassicScript && NS_FAILED(aResult)) {
    nsCOMPtr<nsIParser> parser = do_QueryReferent(mCreatorParser);
    if (parser) {
      parser->IncrementScriptNestingLevel();
    }
    nsresult rv = FireErrorEvent();
    if (parser) {
      parser->DecrementScriptNestingLevel();
    }
    return rv;
  }
  return NS_OK;
}

/* virtual */
nsresult ScriptElement::FireErrorEvent() {
  nsIContent* cont = GetAsContent();

  return nsContentUtils::DispatchTrustedEvent(
      cont->OwnerDoc(), cont, u"error"_ns, CanBubble::eNo, Cancelable::eNo);
}

NS_IMETHODIMP
ScriptElement::ScriptEvaluated(nsresult aResult, nsIScriptElement* aElement,
                               bool aIsInline) {
  nsresult rv = NS_OK;
  if (!aIsInline) {
    nsCOMPtr<nsIContent> cont = GetAsContent();

    RefPtr<nsPresContext> presContext =
        nsContentUtils::GetContextForContent(cont);

    nsEventStatus status = nsEventStatus_eIgnore;
    EventMessage message = NS_SUCCEEDED(aResult) ? eLoad : eLoadError;
    WidgetEvent event(true, message);
    // Load event doesn't bubble.
    event.mFlags.mBubbles = (message != eLoad);

    EventDispatcher::Dispatch(cont, presContext, &event, nullptr, &status);
  }

  return rv;
}

void ScriptElement::CharacterDataChanged(nsIContent* aContent,
                                         const CharacterDataChangeInfo&) {
  MaybeProcessScript();
}

void ScriptElement::AttributeChanged(Element* aElement, int32_t aNameSpaceID,
                                     nsAtom* aAttribute, int32_t aModType,
                                     const nsAttrValue* aOldValue) {
  // https://html.spec.whatwg.org/#script-processing-model
  // When a script element el that is not parser-inserted experiences one of the
  // events listed in the following list, the user agent must immediately
  // prepare the script element el:
  //  - The script element is connected and has a src attribute set where
  //  previously the element had no such attribute.
  if (aElement->IsSVGElement() && ((aNameSpaceID != kNameSpaceID_XLink &&
                                    aNameSpaceID != kNameSpaceID_None) ||
                                   aAttribute != nsGkAtoms::href)) {
    return;
  }
  if (aElement->IsHTMLElement() &&
      (aNameSpaceID != kNameSpaceID_None || aAttribute != nsGkAtoms::src)) {
    return;
  }
  if (mParserCreated == NOT_FROM_PARSER &&
      aModType == MutationEvent_Binding::ADDITION) {
    auto* cont = GetAsContent();
    if (cont->IsInComposedDoc()) {
      MaybeProcessScript();
    }
  }
}

void ScriptElement::ContentAppended(nsIContent* aFirstNewContent) {
  MaybeProcessScript();
}

void ScriptElement::ContentInserted(nsIContent* aChild) {
  MaybeProcessScript();
}

bool ScriptElement::MaybeProcessScript() {
  nsIContent* cont = GetAsContent();

  NS_ASSERTION(cont->DebugGetSlots()->mMutationObservers.contains(this),
               "You forgot to add self as observer");

  // https://html.spec.whatwg.org/#parsing-main-incdata
  // An end tag whose tag name is "script"
  //  - If the active speculative HTML parser is null and the JavaScript
  // execution context stack is empty, then perform a microtask checkpoint.
  nsContentUtils::AddScriptRunner(NS_NewRunnableFunction(
      "ScriptElement::MaybeProcessScript", []() { nsAutoMicroTask mt; }));

  if (mAlreadyStarted || !mDoneAddingChildren || !cont->GetComposedDoc() ||
      mMalformed) {
    return false;
  }

  if (!HasScriptContent()) {
    // In the case of an empty, non-external classic script, there is nothing
    // to process. However, we must perform a microtask checkpoint afterwards,
    // as per https://html.spec.whatwg.org/#clean-up-after-running-script
    if (mKind == JS::loader::ScriptKind::eClassic && !mExternal) {
      nsContentUtils::AddScriptRunner(NS_NewRunnableFunction(
          "ScriptElement::MaybeProcessScript", []() { nsAutoMicroTask mt; }));
    }
    return false;
  }

  // Check the type attribute to determine language and version. If type exists,
  // it trumps the deprecated 'language='.
  nsAutoString type;
  bool hasType = GetScriptType(type);
  if (!type.IsEmpty()) {
    NS_ENSURE_TRUE(nsContentUtils::IsJavascriptMIMEType(type) ||
                       type.LowerCaseEqualsASCII("module") ||
                       type.LowerCaseEqualsASCII("importmap"),
                   false);
  } else if (!hasType) {
    // "language" is a deprecated attribute of HTML, so we check it only for
    // HTML script elements.
    if (cont->IsHTMLElement()) {
      nsAutoString language;
      cont->AsElement()->GetAttr(kNameSpaceID_None, nsGkAtoms::language,
                                 language);
      if (!language.IsEmpty() &&
          !nsContentUtils::IsJavaScriptLanguage(language)) {
        return false;
      }
    }
  }

  Document* ownerDoc = cont->OwnerDoc();
  FreezeExecutionAttrs(ownerDoc);

  mAlreadyStarted = true;

  nsCOMPtr<nsIParser> parser = ((nsIScriptElement*)this)->GetCreatorParser();
  if (parser) {
    nsCOMPtr<nsIContentSink> sink = parser->GetContentSink();
    if (sink) {
      nsCOMPtr<Document> parserDoc = do_QueryInterface(sink->GetTarget());
      if (ownerDoc != parserDoc) {
        // Willful violation of HTML5 as of 2010-12-01
        return false;
      }
    }
  }

  RefPtr<ScriptLoader> loader = ownerDoc->ScriptLoader();
  return loader->ProcessScriptElement(this, type);
}