1 files changed, 181 insertions, 0 deletions
diff --git a/node_modules/parse5/lib/parser/formatting-element-list.js b/node_modules/parse5/lib/parser/formatting-element-list.js
new file mode 100644
index 0000000..0e241db
--- /dev/null
+++ b/node_modules/parse5/lib/parser/formatting-element-list.js
@@ -0,0 +1,181 @@
+'use strict';
+
+//Const
+const NOAH_ARK_CAPACITY = 3;
+
+//List of formatting elements
+class FormattingElementList {
+    constructor(treeAdapter) {
+        this.length = 0;
+        this.entries = [];
+        this.treeAdapter = treeAdapter;
+        this.bookmark = null;
+    }
+
+    //Noah Ark's condition
+    //OPTIMIZATION: at first we try to find possible candidates for exclusion using
+    //lightweight heuristics without thorough attributes check.
+    _getNoahArkConditionCandidates(newElement) {
+        const candidates = [];
+
+        if (this.length >= NOAH_ARK_CAPACITY) {
+            const neAttrsLength = this.treeAdapter.getAttrList(newElement).length;
+            const neTagName = this.treeAdapter.getTagName(newElement);
+            const neNamespaceURI = this.treeAdapter.getNamespaceURI(newElement);
+
+            for (let i = this.length - 1; i >= 0; i--) {
+                const entry = this.entries[i];
+
+                if (entry.type === FormattingElementList.MARKER_ENTRY) {
+                    break;
+                }
+
+                const element = entry.element;
+                const elementAttrs = this.treeAdapter.getAttrList(element);
+
+                const isCandidate =
+                    this.treeAdapter.getTagName(element) === neTagName &&
+                    this.treeAdapter.getNamespaceURI(element) === neNamespaceURI &&
+                    elementAttrs.length === neAttrsLength;
+
+                if (isCandidate) {
+                    candidates.push({ idx: i, attrs: elementAttrs });
+                }
+            }
+        }
+
+        return candidates.length < NOAH_ARK_CAPACITY ? [] : candidates;
+    }
+
+    _ensureNoahArkCondition(newElement) {
+        const candidates = this._getNoahArkConditionCandidates(newElement);
+        let cLength = candidates.length;
+
+        if (cLength) {
+            const neAttrs = this.treeAdapter.getAttrList(newElement);
+            const neAttrsLength = neAttrs.length;
+            const neAttrsMap = Object.create(null);
+
+            //NOTE: build attrs map for the new element so we can perform fast lookups
+            for (let i = 0; i < neAttrsLength; i++) {
+                const neAttr = neAttrs[i];
+
+                neAttrsMap[neAttr.name] = neAttr.value;
+            }
+
+            for (let i = 0; i < neAttrsLength; i++) {
+                for (let j = 0; j < cLength; j++) {
+                    const cAttr = candidates[j].attrs[i];
+
+                    if (neAttrsMap[cAttr.name] !== cAttr.value) {
+                        candidates.splice(j, 1);
+                        cLength--;
+                    }
+
+                    if (candidates.length < NOAH_ARK_CAPACITY) {
+                        return;
+                    }
+                }
+            }
+
+            //NOTE: remove bottommost candidates until Noah's Ark condition will not be met
+            for (let i = cLength - 1; i >= NOAH_ARK_CAPACITY - 1; i--) {
+                this.entries.splice(candidates[i].idx, 1);
+                this.length--;
+            }
+        }
+    }
+
+    //Mutations
+    insertMarker() {
+        this.entries.push({ type: FormattingElementList.MARKER_ENTRY });
+        this.length++;
+    }
+
+    pushElement(element, token) {
+        this._ensureNoahArkCondition(element);
+
+        this.entries.push({
+            type: FormattingElementList.ELEMENT_ENTRY,
+            element: element,
+            token: token
+        });
+
+        this.length++;
+    }
+
+    insertElementAfterBookmark(element, token) {
+        let bookmarkIdx = this.length - 1;
+
+        for (; bookmarkIdx >= 0; bookmarkIdx--) {
+            if (this.entries[bookmarkIdx] === this.bookmark) {
+                break;
+            }
+        }
+
+        this.entries.splice(bookmarkIdx + 1, 0, {
+            type: FormattingElementList.ELEMENT_ENTRY,
+            element: element,
+            token: token
+        });
+
+        this.length++;
+    }
+
+    removeEntry(entry) {
+        for (let i = this.length - 1; i >= 0; i--) {
+            if (this.entries[i] === entry) {
+                this.entries.splice(i, 1);
+                this.length--;
+                break;
+            }
+        }
+    }
+
+    clearToLastMarker() {
+        while (this.length) {
+            const entry = this.entries.pop();
+
+            this.length--;
+
+            if (entry.type === FormattingElementList.MARKER_ENTRY) {
+                break;
+            }
+        }
+    }
+
+    //Search
+    getElementEntryInScopeWithTagName(tagName) {
+        for (let i = this.length - 1; i >= 0; i--) {
+            const entry = this.entries[i];
+
+            if (entry.type === FormattingElementList.MARKER_ENTRY) {
+                return null;
+            }
+
+            if (this.treeAdapter.getTagName(entry.element) === tagName) {
+                return entry;
+            }
+        }
+
+        return null;
+    }
+
+    getElementEntry(element) {
+        for (let i = this.length - 1; i >= 0; i--) {
+            const entry = this.entries[i];
+
+            if (entry.type === FormattingElementList.ELEMENT_ENTRY && entry.element === element) {
+                return entry;
+            }
+        }
+
+        return null;
+    }
+}
+
+//Entry types
+FormattingElementList.MARKER_ENTRY = 'MARKER_ENTRY';
+FormattingElementList.ELEMENT_ENTRY = 'ELEMENT_ENTRY';
+
+module.exports = FormattingElementList;