1 files changed, 147 insertions, 0 deletions
diff --git a/layout/style/CSSVariableValues.h b/layout/style/CSSVariableValues.h
new file mode 100644
index 000000000..e26566be1
--- /dev/null
+++ b/layout/style/CSSVariableValues.h
@@ -0,0 +1,147 @@
+/* vim: set shiftwidth=2 tabstop=8 autoindent cindent expandtab: */
+/* 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/. */
+
+/* computed CSS Variable values */
+
+#ifndef mozilla_CSSVariableValues_h
+#define mozilla_CSSVariableValues_h
+
+#include "nsCSSScanner.h"
+#include "nsDataHashtable.h"
+#include "nsTArray.h"
+
+namespace mozilla {
+
+class CSSVariableResolver;
+
+class CSSVariableValues
+{
+public:
+  CSSVariableValues();
+  CSSVariableValues(const CSSVariableValues& aOther);
+#ifdef DEBUG
+  ~CSSVariableValues();
+#endif
+  CSSVariableValues& operator=(const CSSVariableValues& aOther);
+
+  bool operator==(const CSSVariableValues& aOther) const;
+  bool operator!=(const CSSVariableValues& aOther) const
+    { return !(*this == aOther); }
+
+  /**
+   * Gets the value of a variable in this set of computed variables.
+   *
+   * @param aName The variable name (not including any "--" prefix that would
+   *   be part of the custom property name).
+   * @param aValue Out parameter into which the value of the variable will
+   *   be stored.
+   * @return Whether a variable with the given name was found.  When false
+   *   is returned, aValue will not be modified.
+   */
+  bool Get(const nsAString& aName, nsString& aValue) const;
+
+  /**
+   * Gets the value of a variable in this set of computed variables, along
+   * with information on the types of tokens that appear at the start and
+   * end of the token stream.
+   *
+   * @param aName The variable name (not including any "--" prefix that would
+   *   be part of the custom property name).
+   * @param aValue Out parameter into which the value of the variable will
+   *   be stored.
+   * @param aFirstToken The type of token at the start of the variable value.
+   * @param aLastToken The type of token at the en of the variable value.
+   * @return Whether a variable with the given name was found.  When false
+   *   is returned, aValue, aFirstToken and aLastToken will not be modified.
+   */
+  bool Get(const nsAString& aName,
+           nsString& aValue,
+           nsCSSTokenSerializationType& aFirstToken,
+           nsCSSTokenSerializationType& aLastToken) const;
+
+  /**
+   * Gets the name of the variable at the given index.
+   *
+   * Variables on this object are ordered, and that order is just determined
+   * based on the order that they are added to the object.  A consistent
+   * ordering is required for CSSDeclaration objects in the DOM.
+   * CSSDeclarations expose property names as indexed properties, which need to
+   * be stable.
+   *
+   * @param aIndex The index of the variable to get.
+   * @param aName Out parameter into which the name of the variable will be
+   *   stored.
+   */
+  void GetVariableAt(size_t aIndex, nsAString& aName) const;
+
+  /**
+   * Gets the number of variables stored on this object.
+   */
+  size_t Count() const;
+
+  /**
+   * Adds or modifies an existing entry in this set of variable values.
+   *
+   * @param aName The variable name (not including any "--" prefix that would
+   *   be part of the custom property name) whose value is to be set.
+   * @param aValue The variable value.
+   * @param aFirstToken The type of token at the start of the variable value.
+   * @param aLastToken The type of token at the en of the variable value.
+   */
+  void Put(const nsAString& aName,
+           nsString aValue,
+           nsCSSTokenSerializationType aFirstToken,
+           nsCSSTokenSerializationType aLastToken);
+
+  /**
+   * Copies the variables from this object into aResolver, marking them as
+   * computed, inherited values.
+   */
+  void AddVariablesToResolver(CSSVariableResolver* aResolver) const;
+
+private:
+  struct Variable
+  {
+    Variable()
+      : mFirstToken(eCSSTokenSerialization_Nothing)
+      , mLastToken(eCSSTokenSerialization_Nothing)
+    {}
+
+    Variable(const nsAString& aVariableName,
+             nsString aValue,
+             nsCSSTokenSerializationType aFirstToken,
+             nsCSSTokenSerializationType aLastToken)
+      : mVariableName(aVariableName)
+      , mValue(aValue)
+      , mFirstToken(aFirstToken)
+      , mLastToken(aLastToken)
+    {}
+
+    nsString mVariableName;
+    nsString mValue;
+    nsCSSTokenSerializationType mFirstToken;
+    nsCSSTokenSerializationType mLastToken;
+  };
+
+  /**
+   * Adds all the variables from aOther into this object.
+   */
+  void CopyVariablesFrom(const CSSVariableValues& aOther);
+
+  /**
+   * Map of variable names to IDs.  Variable IDs are indexes into
+   * mVariables.
+   */
+  nsDataHashtable<nsStringHashKey, size_t> mVariableIDs;
+
+  /**
+   * Array of variables, indexed by variable ID.
+   */
+  nsTArray<Variable> mVariables;
+};
+
+} // namespace mozilla
+
+#endif